Correlation Between Cerebral Tissue Oxygen Saturation and Oxygen Extraction Fraction During Anesthesia: Monitoring Cerebral Metabolic Demand-supply Balance During Vasopressor Administration

BACKGROUND

The speculation that cerebral tissue oxygen saturation (SctO 2 ) measured using tissue near-infrared spectroscopy reflects the balance between cerebral metabolic rate of oxygen and cerebral oxygen delivery has not been validated. Our objective was to correlate SctO 2 with cerebral oxygen extraction fraction (OEF) measured using positron emission tomography; OEF is the ratio between cerebral metabolic rate of oxygen and cerebral oxygen delivery and reflects the balance between these 2 variables.

MATERIALS AND METHODS

This cohort study was based on data collected in a previously published trial assessing phenylephrine versus ephedrine treatment in anesthetized patients undergoing brain tumor surgery. The variables of interest were measured twice over the healthy hemisphere before surgery: the first measurement performed after anesthesia induction and the second measurement performed after induction of a ∼20% increase in blood pressure using either phenylephrine or ephedrine.

RESULTS

Data from 24 patients were analyzed. The overall vasopressor-induced relative changes in SctO 2 (ΔSctO 2 ) and OEF (ΔOEF) were 3.16% [interquartile range, -0.73% to 6.04%] and -12.5% [interquartile range, -24.0% to -6.19%], respectively. ΔSctO 2 negatively correlated with ΔOEF after phenylephrine treatment (Spearman rank correlation coefficient [ rs ]=-0.76; P =0.007), ephedrine treatment ( rs =-0.76; P =0.006), and any treatment ( rs =-0.79; P <0.001). ΔSctO 2 significantly associated with ΔOEF based on multivariable analysis with ΔOEF, relative changes in mean arterial pressure, arterial blood oxygen tension, and the bispectral index as covariates ( P =0.036).

CONCLUSIONS

The negative correlation between changes in SctO 2 and OEF suggests that SctO 2 may reflect the cerebral metabolic demand-supply balance during vasopressor treatment. The generalizability of our findings in other clinical scenarios remains to be determined.

Cardiac effects of ephedrine, norephedrine, mescaline, and 3,4-methylenedioxymethamphetamine (MDMA) in mouse and human atrial preparations

The use of recreational drugs like ephedrine, norephedrine, 3,4-methylenedioxymethamphetamine (MDMA), and mescaline can lead to intoxication and, at worst, to death. One reason for a fatal course of intoxication with these drugs might lie in cardiac arrhythmias. To the best of our knowledge, their inotropic effects have not yet been studied in isolated human cardiac preparations. Therefore, we measured inotropic effects of the hallucinogenic drugs ephedrine, norephedrine, mescaline, and MDMA in isolated mouse left atrial (mLA) and right atrial (mRA) preparations as well as in human right atrial (hRA) preparations obtained during cardiac surgery. Under these experimental conditions, ephedrine, norephedrine, and MDMA increased force of contraction (mLA, hRA) and beating rate (mRA) in a time- and concentration-dependent way, starting at 1-3 µM but these drugs were less effective than isoprenaline. Mescaline alone or in the presence of phosphodiesterase inhibitors did not increase force in mLA or hRA. The positive inotropic effects of ephedrine, norephedrine, or MDMA were accompanied by increases in the rate of tension and relaxation and by shortening of time of relaxation and, moreover, by an augmented phosphorylation state of the inhibitory subunit of troponin in hRA. All effects were greatly attenuated by cocaine (10 µM) or propranolol (10 µM) treatment. In summary, the hallucinogenic drugs ephedrine, norephedrine, and MDMA, but not mescaline, increased force of contraction and increased protein phosphorylation presumably, in part, by a release of noradrenaline in isolated human atrial preparations and thus can be regarded as indirect sympathomimetic drugs in the human atrium.

Overlooked switch from transient sedation to sustained excitement in the Biphasic effects of Ephedra Herb extract administered orally to mice

ETHNOPHARMACOLOGICAL RELEVANCE

In our previous study, we reported that Ephedra Herb extract (EHE) increased the locomotor activity of mice in the open-field test and reduced the immobility time in the forced swim test. Ephedrine alkaloids (EAs) are thought to be responsible for the adverse effects of Ephedra Herb. However, there are no reports to verify that the adverse effects of Ephedra Herb are caused by the amount of EAs in the herb. Therefore, we investigated whether these adverse effects of EHE are caused by the amounts of ephedrine (Eph) and pseudoephedrine (Pse) in the herbal extract. In a preliminary study of the time course analysis of the open field test, we newly observed that EHE evoked switching from transient sedation to sustained excitement.

AIM OF THE STUDY

We aimed to confirm whether EHE evokes switching from transient sedation to sustained excitement, investigate whether these actions of EHE are caused by the amount of ephedrine (Eph) and pseudoephedrine (Pse) in the herbal extract, and clarify the molecular mechanism of the transient sedative effect.

MATERIALS AND METHODS

The locomotor activity of mice was tested using the open-field test. The immobility times were measured using a forced swim test, and the motor dysfunction in mice was tested using the rotarod test.

RESULTS

EHE, Eph, and Pse induced transient motionlessness between 0 and 15 min after oral administration, however, they did not induce depression-like behavior and motor dysfunction in mice, suggesting that the motionlessness induced by EHE, Eph, or Pse resulted from sedation. The α2a adrenoceptor inhibitor, atipamezole, decreased their sedative effects. Thus, immediately after EHE administration, the transient sedative effect is mediated through the activation of the α2a adrenoreceptor by Eph and Pse. EHE and Eph increased total locomotor activity for 15-120 min after oral administration; however, Pse had no effect. Therefore, the slow-onset and sustained excitatory effects of EHE are mediated by Eph.

CONCLUSIONS

We discovered for the first time that EHE evokes diphasic action by switching from transient sedation to sustained excitement. The transient sedation was evoked by the Eph and Pse in the herbal extract via activation of the α2a adrenoceptor and the sustained excitement was caused by the Eph in the herbal extract.

Ephedra herb reduces adriamycin-induced testicular toxicity by upregulating the gonadotropin-releasing hormone signalling pathway

OBJECTIVE

We investigated the protective effects of ephedra herb (HEPH) on adriamycin-induced testicular toxicity in rats and explored the potential mechanisms underlying these effects.

METHODS

A rat model of adriamycin injury was established, and sperm motility-related indicator and oxidative stress levels in the testis were evaluated. Serum levels of sex hormones and levels of testicular cell apoptosis were detected by enzyme-linked immunosorbent assay and flow cytometry, respectively. Western blotting (WB), immunofluorescence analyses, and reverse transcription-polymerase chain reaction (RT-PCR) were performed to evaluate the gonadotropin-releasing hormone (GnRH) signalling pathway- and meiosis-related genes and proteins. In subsequent in vitro experiments, adriamycin was used to stimulate GC-1 cells, which were treated with HEPH, ephedrine, or pseudoephedrine. Cell viability was assessed using flow cytometry to detect apoptosis and reactive oxygen species, whereas the GnRH signalling pathway and levels of meiosis-related genes and proteins were evaluated by InCell WB, a high-content imaging system, and RT-PCR.

RESULTS

Per in vivo experiments, HEPH restored testicular weight and function, sperm characteristics, serum and tissue hormonal levels, and antioxidant defences and significantly activated the GnRH signalling pathway- and meiosis-related protein levels. All protective effects of HEPH against adriamycin-induced injury were antagonised by the GnRH antagonist cetrorelix. In vitro, HEPH, ephedrine, and pseudoephedrine significantly reduced adriamycin-induced GC-1 cell apoptosis and reactive oxygen species levels and increased the expression of GnRH signalling pathway- and meiosis-related proteins. The effect of pseudoephedrine was greater than that of ephedrine, and these findings may be an important basis for understanding the effects of HEPH.

Ephedrine ameliorates chronic obstructive pulmonary disease (COPD) through restraining endoplasmic reticulum (ER) stress in vitro and in vivo

Chronic obstructive pulmonary disease (COPD) is a chronic lung disease with limited therapeutic options. Ephedrine (Eph) isolated from Ephedra exerts regulatory role in inflammatory response. However, its effects on COPD development still remain unknown. In the present study, we found that Eph significantly ameliorated apoptosis, oxidative stress and inflammatory response in cigarette smoke extract (CSE)-stimulated human bronchial epithelial cells (HBECs). Moreover, all these cellular events attenuated by Eph were closely associated with reactive oxygen species (ROS) decreasing. Furthermore, we found that the expression of endoplasmic reticulum (ER) stress-associated signaling could be down-regulated by Eph in HBECs without any stimuli. Meanwhile, ER stress was strongly induced by CSE, which was, however, effectively mitigated by Eph exposure in HBECs. Intriguingly, we found that Eph-alleviated cell death, ROS generation and inflammation were almost eliminated by the promotion of ER stress via over-expressing Bip in HBECs upon CSE stimulation. Moreover, Eph administration significantly ameliorated pulmonary indexes and histological impairments in mice with long-term CS exposure, which were largely through the suppression of inflammation, apoptosis and oxidative stress via blocking ER stress as detected in vitro. Collectively, all these findings indicated that Eph exhibited protective effects against CS-caused COPD by hindering ER stress.

Maoto, a traditional Japanese medicine, controls acute systemic inflammation induced by polyI:C administration through noradrenergic function

Maoto, a traditional Japanese medicine (Kampo), is widely used to treat upper respiratory tract infections, including influenza virus infection. Although maoto is known to inhibit pro-inflammatory responses in a rodent model of acute inflammation, its underlying mechanism remains to be determined. In this study, we investigated the involvement of immune responses and noradrenergic function in the inhibitory action of maoto. In a mouse model of polyI:C-induced acute inflammation, maoto was administered orally in conjunction with intraperitoneal injection of PolyI:C (6 mg/kg), and blood was collected after 2 h for measurement of plasma cytokines by ELISA. Maoto significantly decreased PolyI:C-induced TNF-α levels and increased IL-10 production. Neither pretreatment with IL-10 neutralizing antibodies nor T-cell deficiency using nude mice modified the inhibitory effect of maoto, indicating that the anti-inflammatory effects of maoto are independent of IL-10 and T cells. Furthermore, the inhibitory effects of maoto on PolyI:C-induced TNF-α production were not observed in ex vivo splenocytes, suggesting that maoto does not act directly on inflammatory cells. Lastly, pretreatment with a β-adrenergic receptor antagonist partially cancelled the anti-inflammatory effects of maoto. Collectively, these results suggest that maoto mediates its anti-inflammatory effects via β-adrenergic receptors in vivo.

Ephedrine alleviates middle cerebral artery occlusion-induced neurological deficits and hippocampal neuronal damage in rats by activating PI3K/AKT signaling pathway

Inflammation and oxidative stress are crucial in ischemic stroke. Ephedrine (EPH) has been proven to have anti-inflammatory and anti-oxidative stress effects. The present study analyzes whether EPH possessed neuroprotective effects and explored the underlying mechanisms of EPH based on an experimental model of middle cerebral artery occlusion (MCAO). We found that intraperitoneal injection with EPH attenuated the neurological deficit, cerebral infarction, and cerebral edema induced by MCAO in rats. Besides, EPH treatment alleviated MCAO-induced brain tissue damage and morphological abnormality, as well as neuronal loss. Moreover, EPH treatment upregulated GPx and CAT activity and downregulated MDA and NO content. EPH also evidently decreased the levels of IL-6 and TNF-α but increased IL-4 and IL-10 levels. Of note, EPH treatment promoted the phosphorylation of PI3K and AKT proteins in MCAO rats. Furthermore, administration of PI3K/AKT pathway inhibitor LY294002 abolished the beneficial effects of EPH. These results confirmed that EPH alleviated brain injury induced by MCAO via activating PI3K/AKT signaling pathway.

Mechanism deconvolution of Qing Fei Pai Du decoction for treatment of Coronavirus Disease 2019 (COVID-19) by label-free integrative pharmacology assays

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine (TCM) has a long history in the prevention and treatment of pandemics. The TCM formula Lung Cleansing and Detoxifying Decoction (LCDD), also known as Qing Fei Pai Du Decoction, has been demonstrated effective against Coronavirus Disease 2019 (COVID-19).

AIM OF THE STUDY

This work aimed to elucidate the active ingredients, targets and pathway mechanism of LCDD related to suppression of inflammatory, immunity regulation and relaxation of airway smooth muscle for the treatment of COVID-19.

MATERIALS AND METHODS

Mining chemical ingredients reported in LCDD, 144 compounds covering all herbs were selected and screened against inflammatory-, immunity- and respiratory-related GPCRs including GPR35, H1, CB2, B2, M3 and β2-adrenoceptor receptor using a label-free integrative pharmacology method. Further, all active compounds were detected using liquid chromatography-tandem mass spectrometry, and an herb-compound-target network based on potency and content of compounds was constructed to elucidate the multi-target and synergistic effect.

RESULTS

Thirteen compounds were identified as GPR35 agonists, including licochalcone B, isoliquiritigenin, etc. Licochalcone B, isoliquiritigenin and alisol A exhibited bradykinin receptor B2 antagonism activities. Atractyline and shogaol showed as a cannabinoid receptor CB2 agonist and a histamine receptor H1 antagonist, respectively. Tectorigenin and aristofone acted as muscarinic receptor M3 antagonists, while synephrine, ephedrine and pseudoephedrine were β2-adrenoceptor agonists. Pathway deconvolution assays suggested activation of GPR35 triggered PI3K, MEK, JNK pathways and EGFR transactivation, and the activation of β2-adrenoceptor mediated MEK and Ca²⁺. The herb-compound-target network analysis found that some compounds such as licochalcone B acted on multiple targets, and multiple components interacted with the same target such as GPR35, reflecting the synergistic mechanism of Chinese medicine. At the same time, some low-abundance compounds displayed high target activity, meaning its important role in LCDD for anti-COVID-19.

CONCLUSIONS

This study elucidates the active ingredients, targets and pathways of LCDD. This is useful for elucidating multitarget synergistic action for its clinical therapeutic efficacy.

Riparin II potentials the effect of ephedrine on inflammation and remodelling in the airway of rats suffering from asthma by regulating transforming growth factor-β/Smad3 signalling pathway

Asthma is a chronic obstructive lung disorder involving hyperresponsive lung tissue. This study evaluated the protective effects of riparin II against asthma and determined the synergistic effects of riparin II with ephedrine in treatment of asthma. Asthma was induced by intraperitoneal injection of Al(OH)3 (100 mg) with ovalbumin 1 mg/kg and subsequent exposure to 2% ovalbumin aerosol for 1 week. All animals were treated with riparin II 50 mg/kg and ephedrine 25 mg/kg alone and in combination for the duration of the study. Interleukin levels were assessed in the serum and bronchoalveolar lavage fluid (BALF) of asthmatic rats, while inflammatory cell infiltration was determined in the lungs. Airway remodelling was determined by assessing the lung tissue expression levels of transforming growth factor beta 1 (TGF-β1), Smad, and collagen I in asthmatic rats. There were lower levels of cytokines in the serum and BALF in riparin II-treated rats than in negative control rats. Moreover, inflammatory cell and IgE levels were reduced while interferon level was enhanced in the lungs of riparin II-treated rats, compared to negative control rats. These data reveal that treatment with riparin II ameliorates the altered expression of TGF-β1, Smad, and collagen I in lung tissue of asthmatic rats. In conclusion, riparin II treatment alone and in combination with ephedrine ameliorated the hyperresponsiveness of lung tissue due to reductions in airway remodelling and inflammation in asthmatic rats.

Activation of Human Brown Adipose Tissue by Capsinoids, Catechins, Ephedrine, and Other Dietary Components: A Systematic Review

Human brown adipose tissue (BAT) has attracted clinical interest not only because it dissipates energy but also for its potential capacity to counteract obesity and related metabolic disorders (e.g., insulin resistance and dyslipidemia). Cold exposure is the most powerful stimulus for activating and recruiting BAT, and this stimulatory effect is mediated by the transient receptor potential (TRP) channels. BAT can also be activated by other receptors such as the G-protein-coupled bile acid receptor 1 (GPBAR1) or β-adrenergic receptors. Interestingly, these receptors also interact with several dietary components; in particular, capsinoids and tea catechins appear to mimic the effects of cold through a TRP-BAT axis, and they consequently seem to decrease body fat and improve metabolic blood parameters. This systematic review critically addresses the evidence behind the available human studies analyzing the effect of several dietary components (e.g., capsinoids, tea catechins, and ephedrine) on BAT activity. Even though the results of these studies are consistent with the outcomes of preclinical models, the lack of robust study designs makes it impossible to confirm the BAT-activation capacity of the specified dietary components. Further investigation into the effects of dietary components on BAT is warranted to clarify to what extent these components could serve as a powerful strategy to treat obesity and related metabolic disorders.

Growth of Staphylococcus epidermidis in Anaesthetic Resuscitative Drugs: Implications for Potential Contamination

This controlled laboratory study investigated the survival of Staphylococcus epidermidis (S. epidermidis) over a 24 hour period in four commonly drawn-up anaesthetic resuscitative drugs: suxamethonium, atropine, metaraminol and ephedrine. These drugs were prepared in typical therapeutic concentrations and then inoculated with S. epidermidis. Samples of the inoculated drug preparations were cultured on horse blood agar plates at 0, 2, 6, 12 and 24 hourly intervals and incubated for 24 hours.

Colony counts were performed at the end of the incubation period. Suxamethonium, atropine and metaraminol all showed an inhibitory effect on colony counts within the first six hours. There was a more gradual decline of colony counts over a 24 hour period in the ephedrine solution. This decline was similar to that occurring in the normal saline. It is concluded that suxamethonium, atropine and metaraminol do not support the survival of the common skin contaminant, S. epidermidis over a 24 hour period.

Herbal medicine for sports: a review

The use of herbal medicinal products and supplements has increased during last decades. At present, some herbs are used to enhance muscle strength and body mass. Emergent evidence suggests that the health benefits from plants are attributed to their bioactive compounds such as Polyphenols, Terpenoids, and Alkaloids which have several physiological effects on the human body. At times, manufacturers launch numerous products with banned ingredient inside with inappropriate amounts or fake supplement inducing harmful side effect. Unfortunately up to date, there is no guarantee that herbal supplements are safe for anyone to use and it has not helped to clear the confusion surrounding the herbal use in sport field especially. Hence, the purpose of this review is to provide guidance on the efficacy and side effect of most used plants in sport. We have identified plants according to the following categories: Ginseng, alkaloids, and other purported herbal ergogenics such as Tribulus Terrestris, Cordyceps Sinensis. We found that most herbal supplement effects are likely due to activation of the central nervous system via stimulation of catecholamines. Ginseng was used as an endurance performance enhancer, while alkaloids supplementation resulted in improvements in sprint and cycling intense exercises. Despite it is prohibited, small amount of ephedrine was usually used in combination with caffeine to enhance muscle strength in trained individuals. Some other alkaloids such as green tea extracts have been used to improve body mass and composition in athletes. Other herb (i.e. Rhodiola, Astragalus) help relieve muscle and joint pain, but results about their effects on exercise performance are missing.

Effect of ephedrine and phenylephrine on brain oxygenation and microcirculation in anaesthetised patients with cerebral tumours: study protocol for a randomised controlled trial

INTRODUCTION

During brain tumour surgery, vasopressor drugs are commonly administered to increase mean arterial blood pressure with the aim of maintaining sufficient cerebral perfusion pressure. Studies of the commonly used vasopressors show that brain oxygen saturation is reduced after phenylephrine administration, but unaltered by ephedrine administration. These findings may be explained by different effects of phenylephrine and ephedrine on the cerebral microcirculation, in particular the capillary transit-time heterogeneity, which determines oxygen extraction efficacy. We hypothesised that phenylephrine is associated with an increase in capillary transit-time heterogeneity and a reduction in cerebral metabolic rate of oxygen compared with ephedrine. Using MRI and positron emission tomography (PET) as measurements in anaesthetised patients with brain tumours, this study will examine whether phenylephrine administration elevates capillary transit-time heterogeneity more than ephedrine, thereby reducing brain oxygenation.

METHODS AND ANALYSIS

This is a double-blind, randomised clinical trial including 48 patients scheduled for surgical brain tumour removal. Prior to imaging and surgery, anaesthetised patients will be randomised to receive either phenylephrine or ephedrine infusion until mean arterial blood pressure increases to above 60 mm Hg or 20% above baseline. Twenty-four patients were allocated to MRI and another 24 patients to PET examination. MRI measurements include cerebral blood flow, capillary transit-time heterogeneity, cerebral blood volume, blood mean transit time, and calculated oxygen extraction fraction and cerebral metabolic rate of oxygen for negligible tissue oxygen extraction. PET measurements include cerebral metabolic rate of oxygen, cerebral blood flow and oxygen extraction fraction. Surgery is initiated after MRI/PET measurements and subdural intracranial pressure is measured.

ETHICS AND DISSEMINATION

This study was approved by the Central Denmark Region Committee on Health Research Ethics (12 June 2015; 1-10-72-116-15). Results will be disseminated via peer-reviewed publication and presentation at international conferences.

TRIAL REGISTRATION NUMBER

NCT02713087; Pre-results. 2015-001359-60; Pre-results.

Mahuannin B an adenylate cyclase inhibitor attenuates hyperhidrosis via suppressing β2-adrenoceptor/cAMP signaling pathway

BACKGROUND

Based on the traditional application of traditional Chinese Medicines (TCMs), Ephedra Herba (EH) is used to cure cold fever by inducing sweating, whereas Ephedra Radix (ER) is used to treat hyperhidrosis. Although they come from the same plant, Ephedra sinica Stapf, but have play opposing roles in clinical applications. EH is known to contain ephedrine alkaloids, which is the driver of the physiological changes in sweating, heart rate and blood pressure. However, the active pharmacological ingredients (APIs) of ER and the mechanisms by which it restricts sweating remain unknown.

PURPOSE

The current work aims to discover the hidroschesis APIs from ER, as well as to establish its action mechanism.

METHODS

UPLC-Q/TOF-MS, PCA, and heat map were utilized for identifying the differences between EH and ER. HPLC integrated with a β₂-adrenoceptor (β₂-AR) activity luciferase reporter assay system was used to screen active inhibitors; molecular docking and a series of biological assays centered on β₂-AR-related signaling pathways were evaluated to understand the roles of APIs.

RESULTS

The opposite effect on sweating of EH and ER can be attributed to the APIs of amphetamine-type alkaloids and flavonoid derivatives. Mahuannin B is an effective anti-hydrotic agent, inhibiting the production of cAMP via suppression of adenylate cyclase (AC) activity.

CONCLUSION

The effects of EH and ER on sweat and β₂-AR-related signaling pathway are opposite due to different alkaloids and flavonoids of APIs in EH and ER. The present work not only sheds light on the hidroschesis action of mahuannin B, but also presents a potential target of AC in the treatment of hyperhidrosis.

[Treatment of anaphylactic schock in pregnant women]

This is an update on the treatment of anaphylactic shock in pregnant women. Most guidelines recommend adrenaline as first-line treatment in all patients, but in pregnant patients some recommend ephedrine due to a potential risk of utero-placental hypoperfusion with adrenaline. However, ephedrine is a less potent vasopressor than adrenaline and does not possess the same anti-inflammatory or broncho-dilating effects. As immediate and correct treatment is essential for both the maternal and the fetal outcome, adrenaline should be first-line treatment also in pregnant women.

Two-Hour Nasal Responses after a Single Dose of Ephedrine Nasal Spray in Healthy Males

BACKGROUND

Ephedrine is often used as nasal decongestant. Yet, the clinical study of intranasal ephedrine is scarce. In addition, the study tools may affect the measurement of the nasal patency. This problem has not been concerned.

OBJECTIVE

To investigate the nasal responses after using a single-dose of calibrated ephedrine nasal spray in Thai healthy male volunteers. The study also compared the differences between two methods of nasal patency measurement.

MATERIAL AND METHOD

Healthy males (n = 20) were recruited in a randomized, crossover, 2-day study. Each day was studied for anterior rhinomanometry (RN) or peak nasal inspiratory flow (PNIF). On test day, subjects were given ephedrine nasal spray, and measured by the specific tool for two hours. In addition, the visual analogue scale (VAS), cardiovascular (CVS) parameters, and adverse drug reactions were examined.

RESULTS

A single-dose ephedrine nasal spray significantly changed the nasal airway resistance (NAR), PNIF, and VAS at 5-minute. The NAR via RN was maximally decreased by 43.74±16.3% at 10-minute and returned to baseline at 90-minute. While, PNIF was maximally increased by 31.20±18.4% at 10-minute and returned to baseline at 60-minute. The nasal responses measured by two methods were significantly different at 5-, 15-, and 45-minute. VAS for nasal patency showed significant increases throughout the study period. CVS effects were negligible. Bitter taste was the most common adverse event reported.

CONCLUSION

Ephedrine nasal spray is a fast-onset, short-acting decongestant. The decongestant effect of the drug varied by study tools. The variations appeared on the degree of nasal response and duration of action. The drug was generally safe.

cAMP Response Element Binding Protein Expression in the Hippocampus of Rhesus Macaques with Chronic Ephedrine Addiction

BACKGROUND

Drug addiction is classified as a chronic relapse nature brain disease with complicated neurobiology mechanisms. There are an increasing number of researchers that are investigating the possible mechanisms for solving the thorny problem.

METHODS

The model of chronic addiction of rhesus monkey ephedrine was established, where changes in body weight and behavior were monitored. The expression of cAMP response element binding protein (CREB) in the hippocampus of rhesus monkeys was identified by real-time PCR and Western blot.

RESULTS

We were successful in establishing the chronic ephedrine addiction model in the rhesus macaques. They exhibited changes in body weight and behavior. Immunofluorescence showed that CREB was expressed in the nucleus of the hippocampus, and the expression of CREB mRNA and protein in the hippocampus were increased by real-time PCR and Western blot. The CREB positive expression in the hippocampus of the modeling group was significantly higher than in the control group.

CONCLUSIONS

The changes of body weight and behavior of the rhesus monkeys after ephedrine chronic addiction were significant. The changes of CREB in the hippocampus of rhesus macaques with ephedrine chronic addiction are important molecular mechanisms, and the upregulation of CREB may be involved in the physiological pathology and behavior process in individuals with chronic ephedrine addiction.

[Effects of Various Antidepressants on Hemodynamics during General Anesthesia]

BACKGROUND

It is known that serious refractory hypotension during anesthesia may develop in some patients treated with antidepressants. However the detail of this phenomenon remains unclear.

METHODS

We performed a retrospective study based on written anesthesia records from April 2011 through September 2012 (n=5,578). We picked up patients who had received various types of antidepressants. We excluded cases in which neuraxial anesthesia had been performed, and preoperative general condi- tion or performed operation had affected hemodynam- ics greatly. 91 of 5,578 patients were included. All 91 patients received general anesthesia using propofol. We checked type of antidepressants taken and use of vasopressors during anesthesia.

RESULTS

Type of antidepressants taken by 91 patients had no effect on the frequency of vasopressor administration. However, 7 of 91 patients showed treatment-resistant refractory hypotension by ephed- rine and phenylephrine. Catecholamines (noradrenaline, dobutamine) were effective. Frequency of refractory hypotension was significantly higher with serotonin and noradrenaline reuptake inhibitors (SNRI) or with two combined antidepressants.

CONCLUSIONS

Type of antidepressants had no effect on frequency of vasopressor administration. Treat- ment-resistant refractory hypotension by ephedrine and phenylephrine was significantly higher with SNRI or two combined antidepressants. Sympathetic nerve activity may be influenced by interaction of anesthetics and antidepressants in some patients.

Near infrared spectroscopy evaluated cerebral oxygenation during anesthesia

Likely, maintained organ and notably cerebral perfusion, secures rapid recovery following anesthesia. To secure cerebral blood flow (CBF) at least mean arterial pressure (MAP) and the arterial carbon dioxide tension (PaCO₂) need to be considered. CBF is "autoregulated", i.e. stays more or less stable within a MAP of 50-150 mmHg, but the lower limit appears to depend on the central blood volume and/or cardiac output, illustrated by a decrease in CBF at a MAP of 80 mmHg with a compromised central blood volume, while CBF remains constant with a MAP < 40 mmHg, if the central blood volume is maintained. During anesthesia, MAP is often around 50 mmHg meaning that it remains unknown whether CBF is maintained, why an evaluation of CBF, e.g. by near-infrared spectroscopy (NIRS) seems desirable. NIRS is sensitive to changes in PaCOa₂, detects hypoxemia, identifies cerebral autoregulation as well as regional distribution of CBF. As summarized, especially elderly patients and patients undergoing complex surgery and notably heart and liver surgery, seem to benefit from a strategy focusing on maintaining NIRS-determined cerebral oxygenation during anesthesia. Similarly, NIRS may be applied to guide the ventilatory strategy during anesthesia when there are large deviations in metabolism, seen when clamping of the aorta and with reperfusion of the lower body during open aortic surgery, as with hepatectomy and following reperfusion of the donated liver during liver transplantation surgery. Finally, it is illustrated how NIRS can be applied to select sympathomimetic agents, used to correct anesthesia-induced hypotension in order to preserve CBF and skin oxygenation.

A Review of Natural Stimulant and Non-stimulant Thermogenic Agents

Obesity and overweight are major health issues. Exercise and calorie intake control are recognized as the primary mechanisms for addressing excess body weight. Naturally occurring thermogenic plant constituents offer adjunct means for assisting in weight management. The controlling mechanisms for thermogenesis offer many intervention points. Thermogenic agents can act through stimulation of the central nervous system with associated adverse cardiovascular effects and through metabolic mechanisms that are non-stimulatory or a combination thereof. Examples of stimulatory thermogenic agents that will be discussed include ephedrine and caffeine. Examples of non-stimulatory thermogenic agents include p-synephrine (bitter orange extract), capsaicin, forskolin (Coleus root extract), and chlorogenic acid (green coffee bean extract). Green tea is an example of a thermogenic with the potential to produce mild but clinically insignificant undesirable stimulatory effects. The use of the aforementioned thermogenic agents in combination with other extracts such as those derived from Salacia reticulata, Sesamum indicum, Lagerstroemia speciosa, Cissus quadrangularis, and Moringa olifera, as well as the use of the carotenoids as lutein and fucoxanthin, and flavonoids as naringin and hesperidin can further facilitate energy metabolism and weight management as well as sports performance without adverse side effects. © 2016 The Authors Phytotherapy Research published by John Wiley & Sons Ltd.

Chronic ephedrine administration decreases brown adipose tissue activity in a randomised controlled human trial: implications for obesity

AIMS/HYPOTHESIS

Brown adipose tissue (BAT) activation increases energy expenditure and may have therapeutic potential to combat obesity. The primary activating and adaptive signal for BAT is via β-adrenergic signalling. We previously demonstrated that human BAT is acutely responsive to oral administration of the sympathomimetic, ephedrine. Here we aimed to determine whether adaptive thermogenesis can be induced via chronic treatment with ephedrine.

METHODS

Twenty-three healthy young men, recruited from the general public in Melbourne, Australia, who were non-smokers, physically inactive and non-medicated with no prior history of cardiovascular disease or diabetes were recruited for this study. They were assigned to receive either 1.5 mg kg(-1) day(-1) ephedrine ('active' group; n = 12, age 23 ± 1 years, BMI 24 ± 1 kg/m(2)) or placebo (n = 11; 22 ± 2 years, 23 ± 2 kg/m(2)) for 28 days in a randomised (computer-generated random order sequence), placebo-controlled, parallel-group trial. Participants and all investigators were blinded to treatments. Body composition was measured before and after the intervention by dual energy X-ray absorptiometry. BAT activity, measured via (18)F-fluorodeoxyglucose positron emission tomography-computed tomography, in response to a single dose of 2.5 mg/kg ephedrine, was the primary outcome measure to be determined before and after the 28 day treatment period.

RESULTS

Twenty-eight individuals were randomised and consented to the study. Twenty-three completed the trial and only these participants were included in the final analyses. After 28 days of treatment, the active group lost a significant amount of total body fat (placebo 1.1 ± 0.3 kg, ephedrine -0.9 ± 0.5 kg; p < 0.01) and visceral fat (placebo 6.4 ± 19.1 g, ephedrine -134 ± 43 g; p < 0.01), with no change in lean mass or bone mineral content compared with the placebo group. In response to acute ephedrine, BAT activity (change in mean standardised uptake value: placebo -3 ± 7%, ephedrine -22 ± 6%) and the increase in systolic blood pressure were significantly reduced (p < 0.05) in the active group compared with placebo.

CONCLUSIONS/INTERPRETATION

Chronic ephedrine treatment reduced body fat content, but this was not associated with an increase in BAT activity. Rather, chronic ephedrine suppressed BAT glucose disposal, suggesting that chronic ephedrine treatment decreased, rather than increased, BAT activity.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02236962 FUNDING: This study was funded by the National Health and Medical Research Council of Australia Program Grant (1036352) and the OIS scheme from the Victorian State Government.

Cerebral blood flow: physiology, pathophysiology and pharmacological effects

Cerebral blood flow (CBF) is high (mean of 50 ml/100 g. min) to cover metabolic and energy requirements of the brain. Independent from blood pressure in the systemic circulation CBF is kept constant by autoregulation, but it reacts to changes of arterial and tissue pCO2 and to metabolic needs of brain tissue resulting from functional activation. Below defined flow thresholds the function of the nervous tissue is abolished and its morphological integrity destroyed. Due to the regulatory mechanisms only a few drugs are able to affect CBF. The effects depend on the resting blood supply of small regions; this may lead to heterogeneous reaction patterns. The knowledge of drug effects on regional flow may be important in planning a treatment of cerebrovascular disease.

Searching for synergistic bronchodilators and novel therapeutic regimens for chronic lung diseases from a traditional Chinese medicine, Qingfei Xiaoyan Wan

Classical Chinese pharmacopeias describe numerous excellent herbal formulations, and each prescription is an outstanding pool of effective compounds for drug discovery. Clarifying the bioactivity of the combined mechanisms of the ingredients in complex traditional Chinese medicine formulas is challenging. A classical formula known as Qingfei Xiaoyan Wan, used clinically as a treatment for prevalent chronic lung disease, was investigated in this work. A mutually enhanced bioactivity-guided ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) characterization system was proposed, coupled with a dual-luciferase reporter assay for β₂AR-agonist cofactor screening. Arctiin, arctigenin, descurainoside and descurainolide B, four lignin compounds that showed synergistic bronchodilation effects with ephedrine, were revealed. The synergistic mechanism of arctigenin with the β₂ARagonist involved with the reduction of free Ca²⁺ was clarified by a dual-luciferase reporter assay for intracellular calcium and the Ca²⁺ indicator fluo-4/AM to monitor changes in the fluorescence. The relaxant and contractile responses of airway smooth muscle are regulated by crosstalk between the intracellular cAMP and calcium signaling pathways. Our data indicated the non-selective βAR agonist ephedrine as the principal bronchodilator of the formula, whereas the lignin ingredients served as adjuvant ingredients. A greater understanding of the mechanisms governing the control of these pathways, based on conventional wisdom, could lead to the identification of novel therapeutic targets or new agents for the treatment of asthma and COPD.

Muscle uncoupling protein 3 expression is unchanged by chronic ephedrine/caffeine treatment: results of a double blind, randomised clinical trial in morbidly obese females

Ephedrine/caffeine combination (EC) has been shown to induce a small-to-moderate weight loss in obese patients. Several mechanisms have been proposed, among which an increased thermogenic capacity of skeletal muscle consequent to the EC-induced up-regulation of uncoupling protein 3 (UCP3) gene expression. We did a parallel group double-blind, placebo-controlled, 4-week trial to investigate this hypothesis. Thirteen morbidly obese women (25-52 years of age, body-mass index 48.0±4.0 kg/m2, range 41.1-57.6) were randomly assigned to EC (200/20 mg, n = 6) or to placebo (n = 7) administered three times a day orally, before undergoing bariatric surgery. All individuals had an energy-deficit diet equal to about 70% of resting metabolic rate (RMR) diet (mean 5769±1105 kJ/day). The RMR analysed by intention to treat and the UCP3 (long and short isoform) mRNA levels in rectus abdominis were the primary outcomes. Body weight, plasma levels of adrenaline, noradrenaline, triglycerides, free fatty acids, glycerol, TSH, fT4, and fT3 were assessed, as well as fasting glucose, insulin and HOMA index, at baseline and at the end of treatments. Body weight loss was evident in both groups when compared to baseline values (overall -5.2±3.2%, p<0.0001) without significant differences between the treated groups. EC treatment increased the RMR (+9.2±6.8%, p = 0.020), differently from placebo which was linked to a reduction of RMR (-7.6±6.5%, p = 0.029). No significant differences were seen in other metabolic parameters. Notably, no changes of either UCP3 short or UCP3 long isoform mRNA levels were evident between EC and placebo group. Our study provides evidence that 4-week EC administration resulted in a pronounced thermogenic effect not related to muscle UCP3 gene expression and weight loss in morbidly obese females under controlled conditions.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02048215.

Chromatographic isolation of nanoparticles from Ma-Xing-Shi-Gan-Tang decoction and their characterization

ETHNOPHARMACOLOGICAL RELEVANCE

The herbal decoction is a complex dispersion system containing solutes, colloid, aggregates, emulsions and precipitates. In which phase bioactive phytochemicals are dispersed determines their delivery, action and metabolism. This study took ephedrine, a well-studied and widely used phytochemical, as an example to elucidate its exact distribution in the phases of Ma-Xing-Shi-Gan-Tang decoction (MXSGT), which is an Ephedra sinica Stapf. containing traditional Chinese medicinal formula, and the biological meaning of this distribution correspondingly. It may provide an important update to the safety and efficacy assessment of the herbal decoction and its active phytochemicals.

MATERIALS AND METHODS

In this study, the decoction was fractionated with size-exclusion chromatography coupled with multi-angle laser light scattering detector. The morphology of fractionated nanoparticles was observed with AFM and SEM. The bioactivities of the decoction, the ephedrine alkaloids loaded NPs (prepared by chromatography isolation) and the synthetic ephedrine were assessed by cell proliferation tests using five cell lines, namely Caco-2, L-02, Hep-G2, NR-8383, and Hela-229.

RESULTS

Nanoparticles with radii of gyration ranged from 50 to 150 nm were isolated, in spherical shape. Further analysis of nanoparticles on the subsequent reversed phase chromatography revealed that the majority of ephedrine (99.7%) and pseudoephedrine (95.5%) were associated with these nanoparticles, rather than dispersed freely in the real solution. The addition of both the herbal decoction and the separated ephedrine-loaded nanoparticles reserved higher cell viability/proliferation than that of the sole synthetic ephedrine among the Caco-2, L-02, Hep-G2, and NR-8383 cells. In contrast, the nanoparticles reduced the proliferating power of ephedrine on Hela-229 cells. In general, the ephedrine-loaded NPs conducted the intermediate influences on the cell viability, in either way.

CONCLUSIONS

The colloidal nanoparticles were separated from the decoction. The association of ephedrine alkaloids with nanoparticles was demonstrated and may have changed the bioactivity of the alkaloids. The naturally occurred colloidal nanoparticles may play an important role in the pharmacological properties of both the decoction and its active phytochemicals, therefore warrant further studies.

Alkaloids and athlete immune function: caffeine, theophylline, gingerol, ephedrine, and their congeners

Plant alkaloids are found in foods, beverages, and supplements consumed by athletes for daily nutrition, performance enhancement, and immune function improvement. This paper examined possible immunomodulatory roles of alkaloids in exercise contexts, with a focus on human studies. Four representative groups were scrutinized: (a) caffeine (guaranine, mateine); (b) theophylline and its isomers, theobromine and paraxanthine; (c) ginger alkaloids including gingerols and shogaol; and (d) ephedra alkaloids such as ephedrine and pseudoephedrine. Emerging or prospective alkaloid sources (Goji berry, Noni berry, and bloodroot) were also considered. Human in vitro and in vivo studies on alkaloids and immune function were often conflicting. Caffeine may be immunomodulatory in vivo depending on subject characteristics, exercise characteristics, and immune parameters measured. Caffeine may exhibit antioxidant capacities. Ginger may exert in vivo anti-inflammatory effects in certain populations, but it is unclear whether these effects are due to alkaloids or other biochemicals. Evidence for an immunomodulatory role of alkaloids in energy drinks, cocoa, or ephedra products in vivo is weak to nonexistent. For alkaloid sources derived from plants, variability in the reviewed studies may be due to the presence of unrecognized alkaloids or non-alkaloid compounds (which may themselves be immunomodulatory), and pre-experimental factors such as agricultural or manufacturing differences. Athletes should not look to alkaloids or alkaloid-rich sources as a means of improving immune function given their inconsistent activities, safety concerns, and lack of commercial regulation.

[Ligands of cholinesterases of ephedrine and pseudoephedrine structure]

The paper is a review of literature data on interaction of the mammalian erythrocyte acetylcholinesterase and blood serum butyrylcholinesterase with a group of isomer complex ester derivatives (acetates, propionates, butyrates, valerates, and isobutyrates) of bases and iodomethylates of ephedrine and its enantiomer pseudoephedrine. For 20 alkaloid monoesters, parameters of enzymatic hydrolysis are determined and their certain specificity toward acetylcholinesterase is revealed, whereas 5 diesters of iodomethylates of pseudoephedrine were hydrolyzed only by butyrylcholinesterase. The studied 20 aklaloid diesters and 10 trimethylammonium derivatives turned out to be non-competitive reversible inhibitors of acetylcholinesterase and competitive inhibitors of butyrylcholinesterase. The performed for the first time isomer and enantiomer analysis "structure-efficiency" has shown that in most cases it is possible to state the greater comlementarity of the catalytical surface of enzymes for ligands of the pseudoephedrine structure, such differentiation being realized more often at the reversible inhibition of enzymes. pseudoephedrine.

The effect of leptin, caffeine/ephedrine, and their combination upon visceral fat mass and weight loss

OBJECTIVE

To evaluate the effects of combination caffeine/ephedrine and leptin A-200 on visceral fat mass and weight loss over 24 weeks.

DESIGN AND METHODS

In this randomized, double-blind, parallel-arm trial, 90 obese subjects received one of the three treatments for 24 weeks: 200 mg caffeine/20 mg ephedrine t.i.d. (CE), leptin A-200 (recombinant methionyl human Fc-leptin, 20 mg q.d.) (L), or combination leptin A-200 and caffeine/ephedrine (LCE). Outcomes included change in weight, visceral fat mass by computed tomography, lean mass and fat mass by dual energy X-ray absorptiometry.

RESULTS

Groups treated with CE and LCE lost significant amounts of weight (-5.9 ± 1.2% and -6.5 ± 1.1%, P < 0.05) and whole body fat mass (-9.6 ± 2.4% and -12.4 ± 2.3%, P < 0.05) compared to leptin only group. Only treatment with LCE significantly reduced visceral fat mass (-11.0 ± 3.3%, P < 0.05). There were no differences in lean mass between treatment groups.

CONCLUSIONS

Our study provides evidence that CE is a modestly effective weight loss agent and produces significant reductions in fat mass. Leptin A-200 was not effective in producing weight loss and did not have any significant additive or synergistic actions when combined with CE.

To press or not to press, and if so, with what? A single question-focused meta-analysis of vasopressor choice during regional anesthesia in obstetrics

Given the underlying assumption that reasonable maternal hemodynamics can be achieved with either ephedrine or phenylephrine, this focused meta-analysis addresses the impact of vasopressor choice on resultant neonatal Apgar scores during regional anesthesia. The literature was systematically searched for randomized trials of obstetric vasopressor use employing standard search tools. Only the highest quality trials were included. Of 142 studies retrieved, 9 met the defined inclusion criteria. Apgar scores at 1 and 5 minutes in the ephedrine group (served as control) vs the phenylephrine group did not differ at either time epoch; no abnormal values prevailed in either group (relative risk, 0.88; CI, 0.79-1.16). This meta-analysis focused on the most clinically relevant, immediately available information pertinent in the obstetric suite, the Apgar score, and found that ephedrine and phenylephrine did not differ in their effect on this metric. The current meta-analysis provides an updated, evidence-based validation of vasopressor use from the American Society of Anesthesiologists' 2007 "Practice Guidelines for Obstetric Anesthesia".

Dissociations in the effects of β2-adrenergic receptor agonists on cAMP formation and superoxide production in human neutrophils: support for the concept of functional selectivity

In neutrophils, activation of the β2-adrenergic receptor (β2AR), a Gs-coupled receptor, inhibits inflammatory responses, which could be therapeutically exploited. The aim of this study was to evaluate the effects of various β2AR ligands on adenosine-3',5'-cyclic monophosphate (cAMP) accumulation and N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP)-induced superoxide anion (O2(•-)) production in human neutrophils and to probe the concept of ligand-specific receptor conformations (also referred to as functional selectivity or biased signaling) in a native cell system. This is an important question because so far, evidence for functional selectivity has been predominantly obtained with recombinant systems, due to the inherent difficulties to genetically manipulate human native cells. cAMP concentration was determined by HPLC/tandem mass spectrometry, and O2(•-) formation was assessed by superoxide dismutase-inhibitable reduction of ferricytochrome c. β2AR agonists were generally more potent in inhibiting fMLP-induced O2(•-) production than in stimulating cAMP accumulation. (-)-Ephedrine and dichloroisoproterenol were devoid of any agonistic activity in the cAMP assay, but partially inhibited fMLP-induced O2(•-) production. Moreover, (-)-adrenaline was equi-efficacious in both assays whereas the efficacy of salbutamol was more than two-fold higher in the O2(•-) assay. Functional selectivity was visualized by deviations of ligand potencies and efficacies from linear correlations for various parameters. We obtained no evidence for involvement of protein kinase A in the inhibition of fMLP-induced O2(•-) production after β2AR-stimulation although cAMP-increasing substances inhibited O2(•-) production. Taken together, our data corroborate the concept of ligand-specific receptor conformations with unique signaling capabilities in native human cells and suggest that the β2AR inhibits O2(•-) production in a cAMP-independent manner.

Ephedrine activates brown adipose tissue in lean but not obese humans

AIMS/HYPOTHESIS

Brown adipose tissue (BAT) activation increases energy consumption and may help in the treatment of obesity. Cold exposure is the main physiological stimulus for BAT thermogenesis and the sympathetic nervous system, which innervates BAT, is essential in this process. However, cold-induced BAT activation is impaired in obese humans. To explore the therapeutic potential of BAT, it is essential to determine whether pharmacological agents can activate BAT.

METHODS

We aimed to determine whether BAT can be activated in lean and obese humans after acute administration of an orally bioavailable sympathomimetic. In a randomised, double-blinded, crossover trial, we administered 2.5 mg/kg of oral ephedrine to nine lean (BMI 22 ± 1 kg/m²) and nine obese (BMI 36 ± 1 kg/m²) young men. On a separate day, a placebo was administered to the same participants. BAT activity was assessed by measuring glucose uptake with [¹⁸F]fluorodeoxyglucose and positron emission tomography-computed tomography imaging.

RESULTS

BAT activity was increased by ephedrine compared with placebo in the lean, but unchanged in the obese, participants. The change in BAT activity after ephedrine compared with placebo was negatively correlated with various indices of body fatness.

CONCLUSIONS/INTERPRETATION

BAT can be activated via acute, oral administration of the sympathomimetic ephedrine in lean, but not in obese humans.

Evaluation of TAPSE as a measure of right ventricular output

PURPOSE

This study was designed to show the relationship between tricuspid annular plane systolic excursion (TAPSE) and stroke volume (SV) by thermodilution using three different methods and also to assess whether TAPSE can track hemodynamic changes associated with volume loading and ephedrine administration.

METHODS

This was an observational study in 61 elective patients with a pulmonary artery catheter who were undergoing coronary artery bypass graft surgery in a cardiac surgical centre. We measured TAPSE by three methods using transesophageal echocardiography: M mode, speckle tracking at the lateral wall, and tissue tracking at the inferior wall. There were two interventions: leg raising (volume recruitment) or administration of ephedrine 5 mg iv. Echo and hemodynamic measurements were performed before and after each intervention.

RESULTS

Eleven patients were excluded due to poor imaging. There were 26 patients in the leg raising group and 24 patients in the ephedrine group. The correlation coefficient between stroke volume (SV) and TAPSE by M mode, speckle tracking, and tissue tracking was 0.48, 0.44, and 0.09, respectively. There was a significant increase in SV following each intervention; however, the changes in TAPSE by any method and velocity were not large enough to reach statistical significance.

CONCLUSION

Tricuspid annular plane systolic excursion by M mode and by speckle tracking correlates modestly with SV. There was no correlation between TAPSE and SV by tissue tracking at the inferior wall of the right ventricle. Tricuspid annular plane systolic excursion by M mode and by speckle tracking does not track changes in SV following either volume loading or ephedrine administration.

[Comparison of effects in puerpera and fetus with ephedrine and phenylephrine during a cesarean delivery]

OBJECTIVE

To compare the different effects in fetus and puerpera with an equivalent dose of ephedrine (E) and phenylephrine (Ph) for maintaining maternal blood pressure near baseline during spinal anesthesia for a cesarean delivery.

METHODS

Ninety mature parturient women with single-embryo scheduled for an elective cesarean delivery under spinal anesthesia at our hospital during January-June 2010 were randomly divided into 3 groups (E, E + Ph and Ph, n = 30 each). Group E received an infusion of ephedrine (ephedrine 4 g/L), Group E + Ph ephedrine plus phenylephrine (ephedrine 2 g/L + phenylephrine 25 mg/L) and Group Ph phenylephrine (phenylephrine 50 mg/L). The blood pressure was maintained near baseline by adjusting the infusion rate during anesthesia. The maternal blood pressure, heart rate and fetal heart rate were measured at the time points of 1, 3, 5 and 10 min, skin incision and uterine incision after injecting anesthetic into subarachnoid space. Immediately after delivery, maternal arterial, umbilical arterial and umbilical venous blood samples were withdrawn for the measurements of blood gases and plasma concentrations of lactate and glucose.

RESULTS

The fetal heart rate of groups E and E + Ph significantly increased after infusion [5 min: (150 ± 10) times/min vs (142 ± 13) times/min, (146 ± 10) times/min vs (142 ± 9) times/min, both P < 0.05] while those of group Ph had no significant changes [5 min: (143 ± 9) times/min vs(143 ± 6) times/min, P > 0.05]. The incidence of fetal tachycardia in groups E and E + Ph was greater than that in group Ph. In group E, umbilical arterial and umbilical venous pH and base excess were lower than those in groups E + Ph and Ph [umbilical arterial: 7.20 ± 0.10 vs 7.27 ± 0.05, 7.28 ± 0.03, (-3.1 ± 3.1) mmol/L vs (-0.9 ± 1.7) mmol/L, (-0.3 ± 1.7) mmol/L, umbilical venous:7.29 ± 0.09 vs 7.34 ± 0.03, 7.34 ± 0.03, (-3.3 ± 2.9) mmol/L vs (-2.0 ± 1.7) mmol/L, (-0.9 ± 1.5) mmol/L, all P < 0.05]. Umbilical arterial PCO2 and plasma concentrations of lactate and glucose in group E were greater than those in group Ph (all P < 0.05). Umbilical arterial and umbilical venous plasma concentrations of lactate and glucose were greater in group E + Ph than those in group Ph (all P < 0.05). But base excess was lower (P < 0.05).

CONCLUSION

Phenylephrine may be more ideal for treating the hypotension of spinal anesthesia for a cesarean delivery. It corrects hypotension following spinal anesthesia, improves fetal oxygen supply and demand balance but induces no metabolic excitation in fetus as compared with ephedrine.

[Comparison of behavioral effects of psychoactive drugs between two strains of mice]

OBJECTIVE

To compare the behavioral effects of psychoactive drugs between two strains of mice.

METHODS

The Kunming (KM) and ICR mice were injected intraperitoneally with caffeine (3, 10, 30, 100 mg/kg), ephedrine (3, 10, 30, 100 mg/kg), diazepam (1, 3,1 0 mg/kg) and chloral hydrate (10, 30, 100 mg/kg), respectively. Ten min after injection, the locomotor activity in the open field was recorded for 2 h. The total distance, the distance ratio to total distance and the time in central region were analyzed for each drugs. Thirty min after injection, the latent time in the passive avoidance test was measured in a shuttle box.

RESULTS

Caffeine and diazepam prolonged the latent time, and ephedrine and chloral hydrate decreased the latent time, but there were no differences between the two strains. The two strains of mice exhibited significant differences in the total distance after injection of ephedrine 10 mg/kg, diazepam 3 mg/kg and chloral hydrate 100 mg/kg. Compared to KM mice, ICR mice exhibited an increase in the distance ratio and the time in central region after injection of ephedrine 10-100 mg/kg, but a decrease after diazepam 3-10 mg/kg.

CONCLUSION

KM and ICR mice show no differences in latent time, but significant differences in the total distance, the distance ratio and the time in central region in the locomotor activity. Therefore, selection of mouse strains is important in the study of psychoactive drugs.

Urodynamic and haemodynamic effects of a single oral administration of ephedrine or phenylpropanolamine in continent female dogs

This study investigated the effects of a single oral administration of ephedrine (2 mg/kg) or phenylpropanolamine (PPA) (1.5 mg/kg) on the vesico-urethral and cardiovascular functions in continent female dogs. Urethral pressure profilometry (UPP), arterial blood pressures and heart rate were measured in five control dogs and after single-dose treatment with ephedrine or PPA at T(0), T(2h), T(4h), T(6h), T(12h), T(18h) and T(24h). UPPs were performed under propofol anaesthesia and other measurements were performed on awake dogs. A telemetric urodynamic investigation was performed on three additional dogs for 24 h after the administration of each drug. Urethral pressures increased over 4-6 h and urethral functional lengths increased 2-6h after administration of both drugs. During micturition, a decrease in detrusor pressure coupled with an increase in bladder volume was observed after ephedrine administration and there was also an increase in bladder volume after PPA had been given. With both drugs increased arterial blood pressures at 4-6 h were compensated by a decreased heart rate over 12 h. Urethral function was improved after both ephedrine and PPA, and bladder function also improved during micturition following ephedrine.

Dispositional study of opioids in mice pretreated with sympathomimetic agents

Brain and plasma levels of morphine and codeine were determined by an assay method involving solid-phase extraction and ion-pair reversed phase HPLC. Detection was by a variable wavelength UV-detector (for codeine) and an amperometric electrochemical detector (for morphine) coupled in series. Ephedrine or phenylpropanolamine pretreatment did not interfere with the plasma disposition of morphine, evidenced by overlapping plasma concentration-time profiles. Brain opioid levels were equally unaffected by sympathomimetic pretreatment. The relative ratios of brain to plasma concentrations at the time corresponding to the respective peak anti-nociceptive activity for morphine and codeine revealed no significant differences. It is concluded that single doses of ephedrine and phenylpropanolamine do not affect the disposition of morphine and codeine in mice.

Ephedrine enhances the antinociceptive effect of dexmedetomidine in mice

OBJECTIVES

Dexmedetomidine, a highly selective alpha-2-adrenoceptor agonist, was recently introduced into clinical practice for its sedative and analgesic properties. The purpose of this study was to evaluate whether the psychostimulant drug ephedrine has any effect on dexmedetomidine-induced antinociception and locomotor inhibitor activity in mice in acute application.

METHODS

In both sexes of swiss albino mice; antinociception was assessed with hot-plate test and the locomotor, exploratory activities were assessed with holed open field test. The animals were received; saline + saline, ephedrine (10 mg/kg) + saline, saline + dexmedetomidine (15 μg/kg) and ephedrine (10 mg/kg) + dexmedetomidine (15 μg/kg), intraperitoneally, 30 min before hot plate or holed open field tests.

RESULTS

In the hot plate test in mice, co-administration of 15 μg/kg dexmedetomidine with 10 mg/kg ephedrine intraperitoneally not only enhanced, but also prolonged the duration of antinociception induced by dexmedetomidine. At the same time, the locomotor inhibitory effect of dexmedetomidine was counteracted by ephedrine.

CONCLUSION

We concluded that the combined administration of dexmedetomidine with ephedrine may have beneficial effects in the treatment of pain without causing sedation, which limits the use of dexmedetomidine as an analgesic in humans.

[Effects of intravenous vasopressor on spread of spinal anesthesia with 0.5% hyperbaric bupivacaine for caesarean delivery]

BACKGROUND

It is known that when isobaric bupivacaine is applied for Caesarean delivery, phenylephrine is superior to ephedrine in preventing rostral spread of spinal anesthesia. In this study, we prospectively investigated whether phenylephrine can prevent rostral spread of spinal hyperbaric bupivacaine.

METHODS

We randomly divided 32 patients undergoing Caesarean delivery into two groups: phenylephrine group and ephedrine group. In both groups, after the spinal injection of 2.0 ml of hyperbaric 0.5% bupivacaine, we started continuous intravenous infusion of phenylephrine or ephedrine. Blood pressure and heart rate were recorded every minute. Block height of cold sensation was assessed at 5, 10 and 15 minutes after the spinal injection. We measured umbilical artery pH after birth. Data were analyzed using a statistical software package.

RESULTS

Block height was significantly lower with phenylephrine than with ephedrine at 10 and 15 minutes. Umbilical artery pH was significantly higher with phenylephrine than with ephedrine. Haemodynamic changes were significantly different between the two groups. There were no significant differences in age, BMI and spinal-delivery intervals.

CONCLUSIONS

1. Phenylephrine prevented rostral spread of spinal hyperbaric bupivacaine. 2. Haemodynamic changes were significantly different between the two groups. 3. Umbilical artery pH was significantly higher with phenylephrine than with ephedrine.

Alterations of pre- and postsynaptic noradrenergic signaling in a rat model of adriamycin-induced cardiotoxicity

BACKGROUND

Altered sympathetic nervous system signaling is known to play a role in the cardiotoxicity of the anthracycline chemotherapeutic agents, but the interaction of pre- and postsynaptic function is not well understood.

METHODS AND RESULTS

Our aim was to study the noradrenergic signaling in an established rat model of adriamycin cardiotoxicity (15 mg/kg administered i.p. over 2 weeks) using radiotracers having potential applicability for imaging with positron emission tomography (PET). Ex vivo biodistribution was performed 1 and 3 weeks post-adriamycin treatment with the noradrenaline analogue [(11)C]meta-hydroxyephedrine ([(11)C]HED), beta-adrenergic receptor antagonist [(3)H]CGP12177, and phosphodiesterase-4 inhibitor (R)-[(11)C]rolipram. Cardiac function (echocardiographic parameters) and heart/body weight ratio were not affected. Myocardial retention of [(11)C]HED, [(3)H]CGP12177, and (R)-[(11)C]rolipram were unchanged 1 week post-adriamycin. Compared to controls, 3 weeks post-treatment [(3)H]CGP12177 uptake decreased (left ventricle free wall and septum; P < 0.05), while [(11)C]HED and (R)-[(11)C]rolipram uptake were unaffected. Following acute increase in myocardial noradrenaline levels with desipramine treatment, (R)-[(11)C]rolipram retention increased in the left atrium, right ventricle, left ventricle free wall and septum (P < 0.05) in vehicle-, but not adriamycin-treated animals.

CONCLUSION

Our results suggest that adriamycin-induced toxicity exhibits no change in presynaptic noradrenaline uptake, but decreased beta-adrenergic receptors in cardiac tissues, supporting a role for PET imaging of noradrenaline signaling in the study of anthracycline cardiotoxicity.

[Effects of herba ephedrae, honey-fried herba ephedrae and maxingshigan decoction on autonomic activities of mice]

OBJECTIVE

To discuss the significance of processing and complex prescription with Herba Ephedrae, the effects of Herba Ephedrae, Honey-fried Herba Ephedrae and Maxingshigan decoction on autonomic activities in mice were compared.

METHODS

110 female Kunming mice were divided into 11 groups, namely normal saline group (NS), ephedrine group (E), high dose Herba Ephedrae group (MH-H), moderate dose Herba Ephedrae group (MH-M), low dose Herba Ephedrae group (MH-L) ,high dose Honey-fried Herba Ephedrae group (ZMH-H), moderate dose Honey-fried Herba Ephedrae group (ZMH-M),low dose Honey-fried Herba Ephedrae group (ZMH-L), high dose Maxingshigan decoction group (MX-H), moderate dose Maxingshigan decoction group (MX-M) and low dose Maxingshigan decoction group (MX-L). The numbers of autonomic activity in 15 minutes before intragastric administration (ig), and after ig 0.5, 1, 2, 3, 4 h were determined.

RESULTS

There was interaction between time and groups. There were very significant differences between before ig and all time-points after ig (P < 0.01). 30 minutes after ig,there were significant differences between E and NS,E and ZMH-L,E and MX-L (P < 0.05). 1 h after ig, there were significant differences between MX-M and NS (P < 0.05). 3 h after ig, there were significant differences between MX-M and MH-L (P < 0.05). 30 minutes after ig, both ZMH-L and MX-L could reduce the number of autonomic activity in some extent compare with MH-L. 1 h or 2 h after ig, ZMH-L could reduce the number of autonomic activity in some extent compare with MH-L 4 h after ig, MX-L could reduce the number of autonomic activity in some extent compare with MH-L.

CONCLUSION

Under the condition of this study, regarding autonomic activity as index, both ZMH-L and MX-L can reduce center stimulation in some extent.

The Effects of Ginseng, Ephedrine, and Caffeine on Cognitive Performance, Mood and Energy

A variety of claims regarding the purported energy-enhancing properties of nutritional supplements and food constituents have recently been made. It appears that the supplements most frequently associated with such assertions are ginseng, ephedrine, and caffeine. Claims of increased energy are difficult to evaluate objectively because their meaning is not usually defined or specified. Often it is not clear whether the claims refer to physical or mental energy or both. Furthermore, an agreed upon scientific definition of either physical or mental energy enhancement does not exist. In spite of obvious differences in what the term physical energy, as opposed to mental energy implies, there is no clear scientific consensus on whether there is a difference between the two types of energy. Because the substances in question have been anecdotally associated with improvements in both physical and mental performance, their effects on both functions will be discussed, but with an emphasis placed on cognitive function and mood. Of the three substances discussed, caffeine's effects on cognitive and physical function, mood, and energy are best understood. It is clear that this food/drug enhances these functions when administered in moderate doses. Ephedrine may also enhance certain physical and mental functions related to "energy," but the evidence that ginseng has such properties is exceedingly weak.

Efficacy of preanesthetic intramuscular administration of ephedrine for prevention of anesthesia-induced hypotension in cats and dogs

To determine if the preanesthetic administration of ephedrine would prevent anesthesia-induced hypotension in dogs and cats, 10 cats were anesthetized with acepromazine, butorphanol, ketamine, and isoflurane, and 8 dogs were anesthetized with acepromazine, morphine, propofol, and halothane. Cats received ephedrine or saline 10 minutes after premedication. Dogs received ephedrine or saline at the time of premedication. Systolic arterial blood pressure, respiratory rate, heart rate, end-tidal CO2, O2 saturation, cardiac rhythm, and rectal temperature were recorded.The systolic arterial pressure in cats receiving saline was significantly lower than baseline at 10 minutes after premedication, and systolic arterial pressure was < 80 mmHg for the duration of anesthesia. In cats receiving ephedrine, the systolic arterial pressure was significantly lower than baseline for the duration of anesthesia, but systolic arterial pressure was not < 80 mmHg until 25 min after induction. In dogs, systolic arterial pressure was significantly lower than baseline by 5 and 40 min after pre-medication in dogs receiving saline and ephedrine, respectively. There was no difference in heart rate, respiratory rate, end-tidal CO2, rectal temperature, O2 saturation, or cardiac rhythm among treatment groups. Prophylactic ephedrine delayed, but did not prevent, the onset of hypotension.

Effects of SNS activation on SSRI-induced sexual side effects differ by SSRI

Selective serotonin reuptake inhibitors (SSRIs) are associated with significant sexual side effects. By definition, all SSRIs increase overall serotonin (5HT) by binding to serotonin autoreceptors (5HT(IA)); however, each SSRI has a unique portfolio of secondary binding properties to other neurotransmitters such as norepinephrine (NE). As 5HT(IA) receptors mediate NE neurotransmission, SSRIs that are highly selective for 5HT(IA) are more likely to reduce NE efficiency; however, in SSRIs that are less selective for 5HT(IA), this could be counteracted by secondary binding to NE. Norepinephrine is the major neurotransmitter of the sympathetic nervous system (SNS), which has been shown to mediate genital arousal in women; thus, it is possible that increasing SNS activity in women taking SSRIs that are highly selective for 5HT(IA) may counteract sexual side effects in those women. To test this hypothesis, we conducted a reanalysis of Meston (2004)'s 8-week, double-blind, cross-over, placebo-controlled study of the effects of ephedrine (50 mg taken 1 h prior to sexual activity) on self-reported sexual functioning of women taking paroxetine (N = 5), sertraline (N = 7), or fluoxetine (N = 7). As predicted, women taking SSRIs, which are highly selective for 5HT(IA) (sertraline, paroxetine), showed improvement in sexual arousal and orgasm. By contrast, women taking SSRIs, which are less selective for 5HT(IA) relative to NE (fluoxetine), showed no change or decrease in sexual functioning. These findings have implications for treating certain SSRI-induced sexual side effects.

Evaluation of effect of ephedrine on the transport of drugs from the nasal cavity to the systemic circulation and the central nervous system

It has been shown that vasoconstrictive drugs such as ephedrine derivatives are able to decrease systemic absorption of drugs administered by mucosal surfaces. The present paper set out to evaluate in the rat model the effect of co-administered nasal ephedrine on the absorption of GR138950 in a simple and in a pectin self-gelling formulation. It was hypothetised that a decrease in nasal systemic absorption would lead to an increase in direct nose-to-brain transport as demonstrated by the drug concentration in the olfactory lobes of the brain. It was found that ephedrine administered nasally with the drug in a simple aqueous solution resulted in a significant increase in nasal systemic absorption and also an increase in brain delivery; however, this trend was not observed with the pectin formulations. The pectin formulation with ephedrine resulted in lower systemic absorption of GR138950 and lower brain uptake compared to the simple solution formulation containing ephedrine.

Changes in sensitivity of response distributions to changing reinforcement ratios during exposure to ephedrine, caffeine, and ephedrine-caffeine combinations

Changes in the sensitivity of response distributions to changes in reward distribution (reinforcer distribution sensitivity) were examined when rats were exposed to low and moderate doses of caffeine, ephedrine, and caffeine-ephedrine combinations. The data show significant decreases in sensitivity in response distributions to changes in reward schedule values during exposure to caffeine and ephedrine/caffeine combinations, whereas ephedrine alone resulted in overmatching comparable with baseline and NaCl conditions. Rats treated either with 3.0-mg/kg or 10.0-mg/kg doses of caffeine and all combinations of ephedrine at doses of 1.8 or 5.6 mg/kg with caffeine at 3.0 or 10.0 mg/kg showed reduced sensitivity in response distributions to differences in reinforcement schedule ratios. In contrast, when rats were exposed to ephedrine at 1.8 or 5.6 mg/kg, they maintained or increased the degree of overmatching. Although reinforcer distribution sensitivity was altered, drug exposure did not significantly affect the absolute rates of responding. Bias varied after exposure to caffeine, ephedrine, and their combinations, but not systematically. Finally, whereas the estimates of goodness of fit (r2) to the matching equation showed some decreases during drug exposure, these were neither statistically significant nor correlated with drug dose. These results suggest differential effects of ephedrine and caffeine on the sensitivity of response distributions to changes in reinforcement ratio distributions, with deleterious effects of caffeine and ephedrine/caffeine combinations.

Use of ephedrine and dopamine in dogs for the management of hypotension in routine clinical cases under isoflurane anesthesia

OBJECTIVE

To determine the cardiovascular responses of ephedrine and dopamine for the management of presurgical hypotension in anesthetized dogs.

STUDY DESIGN

Prospective, randomized, clinical trial.

ANIMALS

Twelve healthy client-owned dogs admitted for orthopedic surgery; six per group

METHODS

Prior to surgery, 58 anesthetized dogs were monitored for hypotension [mean arterial pressure (MAP) <60 mmHg] that was not associated with bradycardia or excessive anesthetic depth. Ephedrine (0.2 mg kg(-1), IV) or dopamine (5 microg kg(-1) minute(-1), IV) was randomly assigned for treatment in 12 hypotensive dogs. Ten minutes after the first treatment (Tx(1)-10), ephedrine was repeated or the dopamine infusion rate was doubled. Cardiovascular assessments taken at baseline, Tx(1)-10, and 10 minutes following treatment adjustment (Tx(2)-10) were compared for differences within and between treatments (p < 0.05).

RESULTS

Ephedrine increased cardiac index (CI), stroke volume index (SVI), oxygen delivery index (DO(2)I), and decreased total peripheral resistance (TPR) by Tx(1)-10, while MAP increased transiently (<5 minutes). The second ephedrine bolus produced no further improvement. Dopamine failed to produce significant changes at 5 microg kg(-1) minute(-1), while 10 microg kg(-1) minute(-1) increased MAP, CI, SVI significantly from baseline, and DO(2)I compared with Tx(1)-10. The improvement in CI, SVI, and DO(2)I was not significantly different between treatments at Tx(2)-10.

CONCLUSIONS AND CLINICAL RELEVANCE

In anesthetized hypotensive dogs, ephedrine and dopamine improved cardiac output and oxygen delivery. However, the pressure-elevating effect of ephedrine is transient, while an infusion of dopamine at 10 microg kg(-1) minute(-1) improved MAP significantly by additionally maintaining TPR.

Divergent effects of ephedrine and phenylephrine on cardiovascular hemodynamics of near-term fetal sheep exposed to hypoxemia and maternal hypotension

BACKGROUND

We hypothesized that the administration of ephedrine and phenylephrine for maternal hypotension modifies cardiovascular hemodynamics in near-term sheep fetuses.

METHODS

At 115-136 days of gestation, chronically instrumented, anesthetized ewes with either normal placental function or increased placental vascular resistance after placental embolization were randomized to receive boluses of ephedrine (n = 12) or phenylephrine (n = 12) for epidural-induced hypotension after a short period of hypoxemia. Fetal cardiovascular hemodynamics were assessed by Doppler ultrasonography at baseline, during hypotension and after vasopressor treatment.

RESULTS

During hypotension, fetal PO(2) decreased and proximal branch pulmonary arterial and pulmonary venous vascular impedances increased. Additionally, in the embolized fetuses, the time-velocity integral ratio between the antegrade and retrograde blood flow components of the aortic isthmus decreased. These parameters were restored to baseline conditions by ephedrine but not by phenylephrine. With phenylephrine, weight-indexed left ventricular cardiac output and ejection force decreased in the non-embolized fetuses, and the proportion of isovolumetric contraction time of the total cardiac cycle was elevated in the embolized fetuses.

CONCLUSIONS

After exposure to hypoxemia and maternal hypotension, ephedrine restored all fetal cardiovascular hemodynamic parameters to baseline. Phenylephrine did not reverse fetal pulmonary vasoconstriction or the relative decrease in the net forward flow through the aortic isthmus observed in fetuses with increased placental vascular resistance. Moreover, fetal left ventricular function was impaired during phenylephrine administration.