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Schubert R, Gaynullina D, Shvetsova A, Tarasova OS. Myography of isolated blood vessels: Considerations for experimental design and combination with supplementary techniques. Front Physiol 2023; 14:1176748. [PMID: 37168231 PMCID: PMC10165122 DOI: 10.3389/fphys.2023.1176748] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 04/11/2023] [Indexed: 05/13/2023] Open
Abstract
The study of the mechanisms of regulation of vascular tone is an urgent task of modern science, since diseases of the cardiovascular system remain the main cause of reduction in the quality of life and mortality of the population. Myography (isometric and isobaric) of isolated blood vessels is one of the most physiologically relevant approaches to study the function of cells in the vessel wall. On the one hand, cell-cell interactions as well as mechanical stretch of the vessel wall remain preserved in myography studies, in contrast to studies on isolated cells, e.g., cell culture. On the other hand, in vitro studies in isolated vessels allow control of numerous parameters that are difficult to control in vivo. The aim of this review was to 1) discuss the specifics of experimental design and interpretation of data obtained by myography and 2) highlight the importance of the combined use of myography with various complementary techniques necessary for a deep understanding of vascular physiology.
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Affiliation(s)
- Rudolf Schubert
- Physiology, Institute of Theoretical Medicine, Faculty of Medicine, University of Augsburg, Augsburg, Germany
- *Correspondence: Rudolf Schubert,
| | - Dina Gaynullina
- Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, Russia
| | | | - Olga S. Tarasova
- Faculty of Biology, M.V. Lomonosov Moscow State University, Moscow, Russia
- State Research Center of the Russian Federation, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
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The Influence of an Adrenergic Antagonist Guanethidine on the Distribution Pattern and Chemical Coding of Caudal Mesenteric Ganglion Perikarya and Their Axons Supplying the Porcine Bladder. Int J Mol Sci 2021; 22:ijms22094896. [PMID: 34063103 PMCID: PMC8124201 DOI: 10.3390/ijms22094896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/23/2021] [Accepted: 04/27/2021] [Indexed: 11/17/2022] Open
Abstract
This study was aimed at disclosing the influence of intravesically instilled guanethidine (GUA) on the distribution, relative frequency and chemical coding of both the urinary bladder intramural sympathetic nerve fibers and their parent cell bodies in the caudal mesenteric ganglion (CaMG) in juvenile female pigs. GUA instillation led to a profound decrease in the number of perivascular nerve terminals. Furthermore, the chemical profile of the perivascular innervation within the treated bladder also distinctly changed, as most of axons became somatostatin-immunoreactive (SOM-IR), while in the control animals they were found to be neuropeptide Y (NPY)-positive. Intravesical treatment with GUA led not only to a significant decrease in the number of bladder-projecting tyrosine hydroxylase (TH) CaMG somata (94.3 ± 1.8% vs. 73.3 ± 1.4%; control vs. GUA-treated pigs), but simultaneously resulted in the rearrangement of their co-transmitters repertoire, causing a distinct decrease in the number of TH+/NPY+ (89.6 ± 0.7% vs. 27.8 ± 0.9%) cell bodies and an increase in the number of SOM-(3.6 ± 0.4% vs. 68.7 ± 1.9%), calbindin-(CB; 2.06 ± 0.2% vs. 9.1 ± 1.2%) or galanin-containing (GAL; 1.6 ± 0.3% vs. 28.2 ± 1.3%) somata. The present study provides evidence that GUA significantly modifies the sympathetic innervation of the porcine urinary bladder wall, and thus may be considered a potential tool for studying the plasticity of this subdivision of the bladder innervation.
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McKim DB, Patterson JM, Wohleb ES, Jarrett B, Reader B, Godbout JP, Sheridan JF. Sympathetic Release of Splenic Monocytes Promotes Recurring Anxiety Following Repeated Social Defeat. Biol Psychiatry 2016; 79:803-813. [PMID: 26281717 PMCID: PMC4728074 DOI: 10.1016/j.biopsych.2015.07.010] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 06/19/2015] [Accepted: 07/07/2015] [Indexed: 01/02/2023]
Abstract
BACKGROUND Neuroinflammatory signaling may contribute to the pathophysiology of chronic anxiety disorders. Previous work showed that repeated social defeat (RSD) in mice promoted stress-sensitization that was characterized by the recurrence of anxiety following subthreshold stress 24 days after RSD. Furthermore, splenectomy following RSD prevented the recurrence of anxiety in stress-sensitized mice. We hypothesize that the spleen of RSD-exposed mice became a reservoir of primed monocytes that were released following neuroendocrine activation by subthreshold stress. METHODS Mice were subjected to subthreshold stress (i.e., single cycle of social defeat) 24 days after RSD, and immune and behavioral measures were taken. RESULTS Subthreshold stress 24 days after RSD re-established anxiety-like behavior that was associated with egress of Ly6C(hi) monocytes from the spleen. Moreover, splenectomy before RSD blocked monocyte trafficking to the brain and prevented anxiety-like behavior following subthreshold stress. Splenectomy, however, had no effect on monocyte accumulation or anxiety when determined 14 hours after RSD. In addition, splenocytes cultured 24 days after RSD exhibited a primed inflammatory phenotype. Peripheral sympathetic inhibition before subthreshold stress blocked monocyte trafficking from the spleen to the brain and prevented the re-establishment of anxiety in RSD-sensitized mice. Last, β-adrenergic antagonism also prevented splenic monocyte egress after acute stress. CONCLUSIONS The spleen served as a unique reservoir of primed monocytes that were readily released following sympathetic activation by subthreshold stress that promoted the re-establishment of anxiety. Collectively, the long-term storage of primed monocytes in the spleen may have a profound influence on recurring anxiety disorders.
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Affiliation(s)
- Daniel B. McKim
- Division of Biosciences, College of Dentistry. The Ohio State University, 305 W. 12 Ave Columbus, OH 43210, USA,Department of Neuroscience, College of Medicine, The Ohio State University, 333 W. 10 Ave, Columbus, OH 43210, USA
| | - Jenna M. Patterson
- Division of Biosciences, College of Dentistry. The Ohio State University, 305 W. 12 Ave Columbus, OH 43210, USA,Department of Neuroscience, College of Medicine, The Ohio State University, 333 W. 10 Ave, Columbus, OH 43210, USA
| | - Eric S. Wohleb
- Division of Biosciences, College of Dentistry. The Ohio State University, 305 W. 12 Ave Columbus, OH 43210, USA,Department of Neuroscience, College of Medicine, The Ohio State University, 333 W. 10 Ave, Columbus, OH 43210, USA,Department of Psychiatry, School of Medicine, Yale University, 34 Park Street, New Haven, CT 06510, USA
| | - Brant Jarrett
- Division of Biosciences, College of Dentistry. The Ohio State University, 305 W. 12 Ave Columbus, OH 43210, USA,Department of Neuroscience, College of Medicine, The Ohio State University, 333 W. 10 Ave, Columbus, OH 43210, USA
| | - Brenda Reader
- Division of Biosciences, College of Dentistry. The Ohio State University, 305 W. 12 Ave Columbus, OH 43210, USA
| | - Jonathan P. Godbout
- Department of Neuroscience, College of Medicine, The Ohio State University, 333 W. 10 Ave, Columbus, OH 43210, USA,Institute for Behavioral Medicine Research, The Ohio State University, 460 Medical Center Dr., Columbus, OH 43210, USA,Center for Brain and Spinal Cord Repair, The Ohio State University, 460 W. 12 Ave, Columbus, OH 43210, USA
| | - John F. Sheridan
- Division of Biosciences, College of Dentistry. The Ohio State University, 305 W. 12 Ave Columbus, OH 43210, USA,Institute for Behavioral Medicine Research, The Ohio State University, 460 Medical Center Dr., Columbus, OH 43210, USA,Center for Brain and Spinal Cord Repair, The Ohio State University, 460 W. 12 Ave, Columbus, OH 43210, USA,Corresponding author: John F. Sheridan, 223 IBMR Building, 460 Medical Center Drive, Columbus, OH 43210,
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Hughes J, Vane JR. An analysis of the responses of the isolated portal vein of the rabbit to electrical stimulation and to drugs. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 2010; 30:46-66. [PMID: 19108249 DOI: 10.1111/j.1476-5381.1967.tb02112.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Brodie BB, Chang CC, Costa E. On the mechanism of action of guanethidine and bretylium. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 2009; 25:171-8. [PMID: 19108194 DOI: 10.1111/j.1476-5381.1965.tb01769.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ali MB, Mohamed AH, M AB. Pharmacologica Investigation ofHaplophyllum tuberculatum. ACTA ACUST UNITED AC 2008. [DOI: 10.3109/13880209209054628] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- M. B. Ali
- Medicinal and Aromatic Herbs Research Institute, National Council for Research, P.O. Box 2404, Khartoum, Sudan
| | - A. H. Mohamed
- Medicinal and Aromatic Herbs Research Institute, National Council for Research, P.O. Box 2404, Khartoum, Sudan
| | - A.K. Bashir M
- Medicinal and Aromatic Herbs Research Institute, National Council for Research, P.O. Box 2404, Khartoum, Sudan
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El Tahir KE, Ageel AM, Mekkawi AG, Bashir AK, Mossa JS, Khaled SA. Pharmacological Actions of the Leaves ofSolenostemma argel(Hayne): Spasmolytic and Uterine Relaxant Activities. ACTA ACUST UNITED AC 2008. [DOI: 10.3109/13880208709060913] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Feng S, Li C, Fan J, Chen X. Sequential injection technique for the determination of chlorpromazine hydrochloride in pure form and pharmaceutical formulations. JOURNAL OF ANALYTICAL CHEMISTRY 2007. [DOI: 10.1134/s1061934807030069] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Khalil S, Borham N. Phenothiazine Drug Poly(vinyl chloride) Matrix Membrane Electrodes and Their Use in Pharmaceutical Analysis. Microchem J 1999. [DOI: 10.1006/mchj.1999.1804] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Basavaiah K, Krishnamurthy G. Determination of some antipsychotropic and anticholinergic phenothiazine drugs by vanadium (V) titration. Mikrochim Acta 1999. [DOI: 10.1007/bf01244928] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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BOURA AL, GREEN AF. Adrenergic neurone blockade and other acute effects caused by N-benzyl-N'N"-dimethylguanidine and its ortho-chloro derivative. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1998; 20:36-55. [PMID: 14014418 PMCID: PMC1703738 DOI: 10.1111/j.1476-5381.1963.tb01295.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
N-Benzyl-N'N"-dimethylguanidine sulphate (BW 467C60) and its ortho-chloro derivative (BW 392C60) had adrenergic neurone blocking and sympathomimetic effects resembling those of bretylium and guanethidine in cats, dogs and monkeys, but they were more potent in blocking adrenergic mechanisms in the cat. BW 467C60 was more active than its chloro derivative. Each compound inhibited release of noradrenaline during stimulation of the splenic nerve of cats, and increased smooth muscle responses to adrenaline and noradrenaline. Pressor responses to standard doses of tyramine were also increased except when large doses of BW 467C60 or BW 392C60 were given. The adrenergic neurone block by BW 467C60 was inhibited by dopamine, cocaine and amphetamine in situations in which these amines inhibit the effects of bretylium and guanethidine. In contrast to guanethidine, BW 467C60 and BW 392C60 did not lower the pressor amine content of the iris of cats 24 hr after administration of single doses of the compounds. BW 467C60 depressed the slope of curves relating the frequency of stimuli applied to the cervical sympathetic nerves and the resulting contraction of the nictitating membrane, but the effects of the lower rates of stimulation were preferentially inhibited. Large intravenous doses of BW 467C60 and BW 392C60 blocked autonomic cholinergic mechanisms and caused neuromuscular paralysis of voluntary muscle. These effects were brief, in contrast to the adrenergic neurone blockade. Both BW 467C60 and BW 392C60 were well absorbed from the alimentary tract. In contrast to guanethidine, BW 467C60 did not cause diarrhoea in guinea-pigs.
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Abstract
The early hypotensive action of intravenous guanethidine in rabbits, rats and cats anaesthetized with urethane is reversed after pretreatment with iproniazid. The fall in blood pressure following injection of guanethidine in rabbits is reduced after previous administration of reserpine. Reserpine, like adrenalectomy and splenectomy, suppresses the early pressor effect of guanethidine in cats anaesthetized with chloralose. Guanethidine inhibits the action of tyramine and nicotine, but potentiates the effect of noradrenaline on isolated rabbit atria. Guanethidine is also a weak inhibitor of monoamine oxidase activity. The results are discussed and compared with those shown by reserpine. It is concluded that the early effects of guanethidine are mainly due to the release of endogenous catechol amines.
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DAY MD. Effect of sympathomimetic amines on the blocking action of guanethidine, bretylium and xylocholine. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1998; 18:421-39. [PMID: 13884064 PMCID: PMC1482112 DOI: 10.1111/j.1476-5381.1962.tb01421.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Experiments were carried out in which the adrenergic neurone blocking activity of xylocholine, bretylium and guanethidine was studied by the use of the inhibitory responses of the isolated rabbit ileum to lumbar sympathetic nerve stimulation, and the contractions of the nictitating membrane of the anaesthetized cat in response to stimulation of the cervical sympathetic nerves. In both these preparations, after blockade of the effects of sympathetic nerve stimulation had been produced with xylocholine, bretylium or guanethicdine, the sympathomimetic amines, dexamphetamine, mephentermine, hydroxyamphetamine, ephedrine and phenethylamine, reversed the blockade; if these amines were given first, then the adrenergic neurone blocking agents were ineffective. Tyramine and dopamine were effective on the isolated rabbit ileum but not on the cat's nictitating membrane. Effective antagonism of the adrenergic neurone blocking drugs was also shown by some substances which inhibit mono-amine oxidase but only those which in addition possess sympathomimetic effects. Thus phenelzine, pheniprazine and tranylcypromine were effective whereas iproniazid and nialamide were not. Since xylocholine, bretylium and guanethidine were all antagonized by the same agents, it seems likely that they all produce sympathetic blockade by a similar mechanism. The possibility is discussed that the sympathomimetic amines which antagonize the adrenergic neurone blocking drugs are competing with these substances for the same receptor sites.
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BHAGAT B, SHIDEMAN FE. Mechanism of the positive inotropic responses to bretylium and guanethidine. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1998; 20:56-62. [PMID: 13967966 PMCID: PMC1703759 DOI: 10.1111/j.1476-5381.1963.tb01296.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Isolated, atropinized, rat atria exhibited positive inotropic responses to bretylium, guanethidine and tyramine. These responses were prevented by treatment of the animal with reserpine, or by addition of dichloroisoprenaline to the organ bath. The positive inotropic effects of these compounds on atria from reserpinized animals were restored by incubation of the tissue with noradrenaline. On the basis of these findings it is concluded that the cardiac stimulation by bretylium, guanethidine and tyramine involves the release of catechol amines. The usually reported increase in sensitivity of the myocardium from reserpinized animals to noradrenaline was not observed. The influence of bretylium and guanethidine on cardiac uptake and release of noradrenaline was also studied with the rat. Guanethidine decreased the concentration of catechol amines and inhibited the uptake of exogenous noradrenaline, while bretylium had no effect on either. The decrease in concentration of cardiac catechol amines produced by guanethidine was prevented by treatment of the animal with bretylium or with 1-phenyl-2-hydrazinopropane (pheniprazine), a monoamine oxidase inhibitor.
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HOLTON P, RAND MJ. Sympathetic vasodilatation in the rabbit ear. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1998; 19:513-26. [PMID: 13961468 PMCID: PMC1482209 DOI: 10.1111/j.1476-5381.1962.tb01457.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Changes in the blood content of a 1 cm(2) portion of the intact rabbit's ear were studied with transillumination and a photocell. Stimulation of the post-ganglionic sympathetic nerves produced a decrease in blood content, attributable to vasoconstriction, followed by an increased blood content, attributable to vasodilatation. The vasodilatation was enhanced by eserine and decreased by atropine. Guanethidine abolished the vasoconstriction but not the vasodilatation. After the ganglion had been decentralized by degeneration of the pre-ganglionic sympathetic nerves the vessels had an increased sensitivity to acetylcholine and the vasodilatation in response to sympathetic stimulation was enhanced. It is concluded that sympathetic stimulation results in the liberation of acetylcholine which causes vasodilatation.
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DAY MD, RAND MJ. Evidence for a competitive antagonism of guanethidine by dexamphetamine. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1998; 20:17-28. [PMID: 14025626 PMCID: PMC1703752 DOI: 10.1111/j.1476-5381.1963.tb01293.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
After guanethidine had blocked the response of the cat nictitating membrane to sympathetic nerve stimulation, dexamphetamine restored the responses to all frequencies of stimulation. Dexamphetamine antagonized the sympathetic nerve block by guanethidine in the isolated sympathetically innervated rabbit ileum; the evidence suggests that the antagonism was competitive. Dexamphetamine antagonized the sympathetic nerve block by guanethidine in the isolated hypogastric nerve-vas deferens preparation of the guinea-pig. Doses of dexamphetamine, larger than those required to antagonize the blocking action of guanethidine, abolished the responses of the nictitating membrane, ileum and vas deferens to nerve stimulation. Dexamphetamine did not influence the depletion of noradrenaline by guanethidine in the heart and spleen of rabbits. The hypothesis is advanced that both dexamphetamine and guanethidine act on the store of noradrenaline at sympathetic nerve endings.
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ABERCROMBIE GF, DAVIES BN. The action of guanethidine with particular reference to the sympathetic nervous system. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1998; 20:171-7. [PMID: 14010673 PMCID: PMC1703743 DOI: 10.1111/j.1476-5381.1963.tb01307.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
It has been suggested that guanethidine can release and then deplete postganglionic sympathetic nerve endings of noradrenaline. However, no release of noradrenaline from postganglionic nerve endings or from the adrenal medulla by guanethidine was found by direct experiment. Although release of noradrenaline from postganglionic sympathetic nerve endings in response to nerve stimulation was rapidly reduced and finally abolished by guanethidine, the drug did not appear to affect the release of catechol amines from the adrenal medulla in response to splanchnic nerve stimulation. The nature of the action of guanethidine is discussed, and it is concluded that it blocks the effect of postganglionic sympathetic nerve stimulation by interfering with the synthesis of transmitter and that it also has a direct sympathomimetic effect.
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GAFFNEY TE, CHIDSEY CA, BRAUNWALD E. Study of the relationship between the neurotransmitter store and adrenergic nerve block induced by reserpine and guanethidine. Circ Res 1998; 12:264-8. [PMID: 13946095 DOI: 10.1161/01.res.12.3.264] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The heart rate response to cardioaccelerator nerve stimulation and the corresponding levels of myocardial norepinephrine content were determined and correlated in dogs at various time intervals following the intravenous injection of either 3 mg/kg reserpine, or 10 mg/kg guanethidine. Guanethidine produced complete blockade of the cardiac accelerator response before producing measurable myocardial depletion of norepinephrine. In contrast, reserpine reduced the positive chronotropic response to cardioaccelerator nerve stimulation only after myocardial norepinephrine levels have been reduced to approximately 0.3 µg/g. An infusion of norepinephrine did not restore the heart rate response to cardioaccelerator nerve stimulation in either the reserpine or guanethidine treated dogs. These data suggest that the interference with adrenergic transmission produced by guanethidine is independent of changes in the level of stored adrenergic transmitter. The reserpine-induced blockade of adrenergic transmission may ultimately be dependent upon the mission may ultimately be dependent upon the depletion of adrenergic transmitter, but almost complete depletion of stored adrenergic transmitter must occur before reserpine-induced adrenergic blockade occurs.
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VARAGIC V, VOJVODIC N. Effect of guanethidine, hemicholinium and mebutamate on the hypertensive response to eserine and catechol amines. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1998; 19:451-7. [PMID: 13996274 PMCID: PMC1482221 DOI: 10.1111/j.1476-5381.1962.tb01449.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Guanethidine, hemicholinium and mebutamate were used to study the site and mechanism of the hypertensive response to eserine in the rat. Guanethidine was found to block very effectively the hypertensive effect of eserine and to produce at the same time a very strong potentiation of the response to catechol amines. Hemicholinium, after a certain latent period, also blocked the effect of eserine, at the same time leaving the response to adrenaline and noradrenaline intact. Mebutamate was also found to block the effect of eserine. The results of the present experiments suggest that eserine produces a central adrenergic activation in the rat.
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GOKHALE SD, GULATI OD, JOSHI NY. EFFECT OF SOME BLOCKING DRUGS ON THE PRESSOR RESPONSE TO PHYSOSTIGMINE IN THE RAT. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1996; 21:273-84. [PMID: 14081658 PMCID: PMC1703838 DOI: 10.1111/j.1476-5381.1963.tb01526.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bretylium and guanethidine blocked the pressor effect of physostigmine and potentiated the responses to adrenaline and noradrenaline on the blood pressure of the rat. Morphine and atropine in small doses blocked the pressor effect of physostigmine without interfering with the actions of adrenaline and noradrenaline. Chlorpromazine in small doses (0.5 to 2.5 mg/kg) blocked the pressor effect of physostigmine and potentiated the responses to noradrenaline whilst those to adrenaline remained unaltered. 3,6-Di(3-diethylaminopropoxy)pyridazine di(methiodide) (Win 4981) blocked the pressor effect of physostigmine and, in its early stages, this block was partially reversed by choline chloride. N-Diethylaminoethyl-N-isopentyl-N'N'-diisopropylurea (P-286), in a dose that reduced the effect of dimethylphenylpiperazinium, had no effect on the pressor response to physostigmine or on the responses to adrenaline and noradrenaline. Hexamethonium, even in large doses (100 mg/kg), only blocked partially the effect of physostigmine while mecamylamine produced a complete block; the responses to adrenaline and noradrenaline were potentiated in both instances.
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DELLABELLA D, GANDINI A, PRETI M. THE MECHANISM OF THE PRESSOR RESPONSES TO PHYSOSTIGMINE IN THE RAT AND THEIR MODIFICATION BY MEBUTAMATE AND AMYLOBARBITONE. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1996; 23:540-51. [PMID: 14256813 PMCID: PMC1704002 DOI: 10.1111/j.1476-5381.1964.tb01609.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pressor responses to intravenous injections both of physostigmine and of pilocarpine were smaller in rats anaesthetized with either mebutamate or amylobarbitone than in rats anaesthetized with urethane. The response to electrical stimulation of the hypogastric nerve in the isolated hypogastric nerve-vas deferens preparation was diminished by mebutamate and by amylobarbitone, but not by urethane. Similar results were obtained with the cat isolated splenic nerve-spleen preparation. In the rat anaesthetized with urethane, pressor responses to physostigmine were only partially antagonized by hexamethonium but were completely abolished during "depolarizing" ganglionic block by nicotine or tetramethylammonium. It is suggested that, in addition to the central mechanism, there is a peripheral component in the pressor action of physostigmine and in the antihypertensive actions of mebutamate and amylobarbitone.
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SNYDER SH, AXELROD J. CIRCADIAN RHYTHM IN PINEAL SEROTONIN: EFFECT OF MONOAMINE OXIDASE INHIBITION AND RESERPINE. Science 1996; 149:542-4. [PMID: 14325156 DOI: 10.1126/science.149.3683.542] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The pineal gland of the rat shows a circadian rhythm in its serotonin content, the amount of serotonin decreasing at night. This decrease can be prevented by inhibiting the action of monoamine oxidase. Reserpine abolishes the circadian rhythm in pineal serotonin in the same manner as does interruption of the sympathetic nervous connections of the central nervous system and the pineal gland. These observations suggest that circadian changes in release and binding of serotonin may occur in the pineal gland, and that a central mechanism in which monoamines participate may control the circadian pineal-serotonin rhythm.
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GOKHALE SD, GULATI OD, JOSHI NY. ANTAGONISM OF THE BLOCKING ACTION OF BRETYLIUM AND GUANETHIDINE ON THE PRESSOR EFFECT OF PHYSOSTIGMINE IN THE RAT. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1996; 24:624-31. [PMID: 14340916 PMCID: PMC1704020 DOI: 10.1111/j.1476-5381.1965.tb01618.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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BHAGAT B. MODIFICATION OF THE EFFECTS OF GUANETHIDINE ON CARDIAC CATECHOL AMINES BY VARIOUS AGENTS. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1996; 22:238-45. [PMID: 14190459 PMCID: PMC1703988 DOI: 10.1111/j.1476-5381.1964.tb02029.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A study has been made of the effect of injections of guanethidine in rats, in depleting catechol amines from the whole cardiac ventricles and from various subcellular fractions. Unlike reserpine, guanethidine first affected the concentration of the amines in the soluble fraction of the cell. Neither [2-(2,6-dimethylphenoxy)-propyl]trimethylammonium chloride monohydrate (beta-methyl xylocholine) nor hemicholinium affected the endogenous catechol amines or the uptake of injected noradrenaline, but each significantly reduced the action of guanethidine in depleting catechol amines. Administration of choline chloride after hemicholinium reversed its influence on guanethidine depletion. In cats, cocaine potentiated the pressor response to noradrenaline, but antagonized the response to tyramine and guanethidine, while bretylium and N-o-chlorobenzyl-N'N"-dimethylguanidine sulphate (BW392C60) potentiated the responses to noradrenaline, tyramine and guanethidine.
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SPRIGGS TL. THE EFFECTS OF ANAESTHESIA INDUCED BY URETHANE OR PHENOBARBITONE UPON THE DISTRIBUTION OF PERIPHERAL CATECHOL AMINES IN THE RAT. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1996; 24:752-8. [PMID: 14340929 PMCID: PMC1704032 DOI: 10.1111/j.1476-5381.1965.tb01631.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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FIELDEN R, ROE AM, WILLEY GL. THE ADRENERGIC-NEURONE BLOCKING ACTION OF SOME COUMARAN COMPOUNDS. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1996; 23:486-507. [PMID: 14256809 PMCID: PMC1704011 DOI: 10.1111/j.1476-5381.1964.tb01605.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ethyldimethyl(7-methylcoumaran-3-yl)ammonium iodide (SK&F 90,109) and its guanidine analogue [N-(7-methylcoumaran-3-yl)guanidine nitrate] (SK&F 90,238) abolish the effects of adrenergic nerve stimulation in cats, as do xylocholine and bretylium. SK&F 90,109 has slight sympathomimetic actions; these are less marked than in SK&F 90,238. Large doses of SK&F 90,109 have an action, dependent on local noradrenaline stores, that delays the appearance of adrenergic-neurone blockade in conscious cats. Responses to adrenaline are, in general, enhanced by each drug, but SK&F 90,238 transiently antagonizes tachycardia induced by adrenaline and isoprenaline. Both drugs inhibit the release of noradrenaline from the spleen during splenic nerve stimulation, but the release of catechol amines from the adrenal glands, in response to electrical or chemical stimulation, is unimpaired. In contrast to the prolonged adrenergic-neurone blocking action, any inhibition of the effects of cholinergic nerve stimulation is transient. Large intravenous doses produce neuromuscular blockade. The compounds have a slight central depressant action. In contrast to reserpine and guanethidine the noradrenaline content of rat hearts is not appreciably lowered 24 hr after a single dose of either drug. Unlike xylocholine they are not local anaesthetics. Related compounds also block the effects of adrenergic-nerve stimulation. The possible modes of action of these drugs are discussed.
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Tarasiewicz M, Ku Ÿmicka L. Extractive Spectrophotometric Determinationsl Of Some Phenothiazines with Picric and Flavianic Acids. ANAL LETT 1996. [DOI: 10.1080/00032719608001445] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Korner P, Bobik A, Oddie C, Friberg P. Sympathoadrenal system is critical for structural changes in genetic hypertension. Hypertension 1993; 22:243-52. [PMID: 8340160 DOI: 10.1161/01.hyp.22.2.243] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats, we examined tissue and adrenal norepinephrine concentrations, left ventricular (LV) weight, LV weight/body weight ratio (LV/BW), hindquarter resistance properties, ie, perfusion pressures at maximum dilatation and constriction (PPmax, PPmin), and the slope of the methoxamine log dose-PP curve. In series 1, we studied 4-week-old controls (SHRc, WKYc), sympathectomized rats (SX; SHRsx, WKYsx), and SX rats also given prazosin (SXP; SHRsxp, WKYsxp). With SX and SXP, adrenal norepinephrine concentrations increased in both strains, but tissue (LV, muscle, kidney) norepinephrine was depleted. At 4 weeks, LV/BW, PPmin, and PPmax were all greater in SHRc than in WKYc. With SX, these differences between strains remained unchanged, but SXP abolished them completely, indicating the importance of blockade of alpha-adrenergic receptor stimuli of adrenal origin. In SHRc (but not in WKYc), there was evidence of reinnervation after 4 weeks of SX. Hence, in series 2, the SXP period was extended to 8 weeks, and we studied SHRc, WKYc, SHRsxp, and WKYsxp. Systolic blood pressure was already elevated at 4 weeks in SHRc, and by 35 weeks it was 64 mm Hg greater than in WKYc. At 21 and 35 weeks, LV/BW, PPmax, PPmin, and slopes were all greater in SHRc than in WKYc, and the findings suggested greater LV and vascular hypertrophy than at 4 weeks. In SHRsxp hypertension, LV hypertrophy and the vascular changes were completely prevented over the entire 35-week observation period. SXP mainly affected SHR and had few effects on WKY rats. The sympathetic nerves and adrenals are probably the sources of alpha-adrenergic receptor stimulation in young SHR. They account for the development of hypertension and for most of the cardiovascular structural differences between SHR and WKY rats.
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Affiliation(s)
- P Korner
- Baker Medical Research Institute, Melbourne, Australia
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Ferreira J, Gil L, Stutzin A, Orrego F. Effects of guanethidine on electron transport and proton movements in rat heart, brain and liver mitochondria. Biochem Pharmacol 1985; 34:2507-12. [PMID: 2990489 DOI: 10.1016/0006-2952(85)90534-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Guanethidine at 5-25 mM concentrations was found to induce up to 79% inhibition of ADP-stimulated (state III) oxygen consumption in isolated rat heart, brain or liver mitochondria, when the added substrate was glutamate or succinate, but the inhibition was considerably lower (24% or less) when respiration was supported by ascorbate plus tetramethylphenylenediamine (TMPD). Comparable results were seen regarding ADP-stimulated proton uptake, where even greater inhibition (up to 94% with glutamate or succinate, but not ascorbate plus TMPD) was found. Similar but somewhat less marked effects were also seen in resting (state IV) respiration and on the acceptor control ratio (state III/state IV respiration). 2,4-Dinitrophenol was unable to relieve guanethidine-induced inhibition of electron transport. These results indicate that guanethidine inhibits primarily mitochondrial electron transport itself, and that the site where such inhibition is more marked is located in the span between ubiquinone and cytochrome c of the respiratory chain. It is, therefore, suggested that active guanethidine uptake by noradrenergic neurons can lead to a high drug concentration in their cytoplasm and hence to mitochondrial alterations that can contribute to the pharmacological effect of this drug. Our results demonstrate the interaction between guanethidine and the electron transport chain of mitochondria derived from different tissues and, therefore, support this hypothesis.
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Sakaguchi A, LeDoux JE, Reis DJ. Sympathetic nerves and adrenal medulla: contributions to cardiovascular-conditioned emotional responses in spontaneously hypertensive rats. Hypertension 1983; 5:728-38. [PMID: 6618635 DOI: 10.1161/01.hyp.5.5.728] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
This report investigates the contributions of the sympathetic nerves and adrenal medulla to resting mean arterial pressure (MAP) and to emotionally conditioned MAP and heart rate (HR) responses in unrestrained spontaneously hypertensive rats (SHR) and Wistar-Kyoto normotensive control rats (WKY). Resting MAP (in mm Hg), which was higher in SHR (WKY = 120 +/- 4; SHR = 163 +/- 4; p less than 0.01), did not differ in the two strains following chemosympathectomy (WKY = 105 +/- 2; SHR = 101 +/- 2; n.s.). Adrenal medullectomy did not affect resting MAP in WKY (125 +/- 6; n.s.) but lowered it in SHR (146 +/- 5; p less than 0.05), relative to controls (see above). The conditioned pressor response (in mm Hg) in controls consisted of two peaks (I, II) in both strains, but was exaggerated in SHR (I = WKY, 13 +/- 1; SHR, 25 +/- 2; p less than 0.01; II = WKY 10 +/- 2; SHR 20 +/- 2; p less than 0.01). Chemosympathectomy suppressed (relative to controls) the first peak, but not the second, in both strains (WKY: I = 4 +/- 1, p less than 0.01; II = 12 +/- 2, n.s.; SHR: I = 6 +/- 1, p less than 0.01; II = 15 +/- 2, n.s.). Adrenal medullectomy alone had little effect on the pressor response, but when combined with chemosympathectomy both peaks were largely eliminated (WKY: I = 2 +/- I; II = 5 +/- 1; SHR: I = 1 +/- 0; II = 2 +/- 0). These data indicate that: 1) hypertension in conscious, freely behaving SHR is largely sustained by the sympathetic vasomotor nerves but that the adrenal medulla contributes to the magnitude of the elevation; 2) the early component of the exaggerated pressor response during aversive stimulation is mediated by sympathetic vasomotor excitation; and 3) the later component of the exaggerated pressor response reflects coactivation of the sympathetic vasomotor nerves and the adrenal medulla.
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Bobik A, Korner P. Cardiac beta adrenoceptors and adenylate cyclase in normotensive and renal hypertensive rabbits during changes in autonomic activity. Clin Exp Hypertens 1981; 3:257-80. [PMID: 6260438 DOI: 10.3109/10641968109033664] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The effects of hypertrophy and alterations in cardiac autonomic activity on left ventricular (LV) beta adrenoceptors and adenylate cyclase were measured in rabbits. Normotensive and renal hypertensive animals were exposed to three levels of chronic sympathetic activity: (i) "normal" activity; (ii) reduced activity after 2 weeks treatment with guanethidine; (iii) 2 weeks increased sympathetic activity following sino-aortic denervation. In hypertensive animals with "normal" activity LV beta receptor sarcolemma concentration was reduced by 36+ compared with the normotensive subgroup whilst total LV receptor numbers were unaltered. Isoprenaline activated adenylate cyclase was similarly affected whilst other sarcolemma marker enzymes were unaffected. Chronic guanethidine administration to normotensive rabbits increased beta receptor concentration (16%, P less than 0.05), basal and isoprenaline activated meters were unaffected. Sino-aortic denervation did not significantly affect beta receptor concentration in either group. The small changes in beta receptor concentration during alterations in sympathetic activity suggest that only a small proportion of LV beta receptors appear to be innervated. The reduction in sarcolemma beta receptor concentration in hypertensive animals appears to be a specific effect due to hypertrophy of the cardiocyte.
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36
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Abstract
1 In chloralose-anaesthetized dogs pretreated with guanethidine and pancuronium, electrical stimulation (0.2 to 5 Hz) of the peripheral end of the cut tibial nerve caused a frequency-dependent increase in femoral blood flow which was restricted to the paw pads. 2 This neurogenic vasodilatation was not attenuated by atropine, mepyramine plus burimamide, indomethacin or propranolol. It was, however, attenuated in a dose-dependent manner by intra-arterial administration of the dopamine receptor antagonist, ergometrine (0.05 to 0.5 mg). 3 The effect of ergometrine could not be explained by non-specific effects on axonal conduction or transmission or by vasospasm of the blood vessels of the paw-pads. 4 In dogs with intact tibial nerves, a pharmacologically similar dilator response localized to the paw-pads could be elicited by electrical stimulation of loci in the ipsilateral diencephalon and midbrain. This response was not due to inhibition of adrenergic vasomotor tone and was abolished by systemic ganglion blockade or by tibial nerve section as well as by femoral arterial administration of ergometrine. 5 It is suggested that the vasculature of the canine paw pads is innervated by a population of autonomic axons which utilize dopamine or a related substance as a transmitter substance and activation of which causes vasodilation.
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Khan MT, Wakade AR. Relationship between accumulation, storage and overflow of noradrenaline in the rat salivary gland after chronic treatment with guanethidine. Br J Pharmacol 1979; 66:223-8. [PMID: 465874 PMCID: PMC2043645 DOI: 10.1111/j.1476-5381.1979.tb13669.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
1 The effect of guanethidine on the endogenous noradrenaline (NA) content, accumulation and overflow of [3H]-noradrenaline ([3H]-NA) in the rat salivary gland was examined at various times after drug administration. 2 Twenty-four h after a single injection of guanethidine (1 or 10 mg/kg s.c.), the respective values for the endogenous NA content and for the accumulation and overflow of [3H]-NA were approximately 55, 85, 30%, and 15, 55, 10% of the controls. 3 Although [3H]-NA accumulation had returned to control levels within 48 h after the dose of 10 mg/kg guanethidine, the overflow of [3H]-NA evoked by electrical stimulation or excess potassium (K+) remained depressed. 4 After the low or the high dose of guanethidine, the NA content of the salivary gland was restored to about 50% of the normal value between 4 to 24 and 48 to 72 h, respectively. 5 The accumulation of [3H]-NA was inhibited by about 75% by cocaine. The same degree of inhibition was obtained 4 h after 10 mg/kg guanethidine. In these experiments phenoxybenzamine did not reduce the residual (25%) uptake. 6 The reasons for differential rates of recovery of the endogenous NA content and the storage of [3H]-NA after guanethidine are discussed.
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Bell C, Lang WJ, Laska F. Dopamine-containing axons supplying the arterio-venous anastomoses of the canine paw pad. J Neurochem 1978; 31:1329-33. [PMID: 702177 DOI: 10.1111/j.1471-4159.1978.tb06259.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Wakshull E, Johnson MI, Burton H. Persistence of an amine uptake system in cultured rat sympathetic neurons which use acetylcholine as their transmitter. J Cell Biol 1978; 79:121-31. [PMID: 701368 PMCID: PMC2110229 DOI: 10.1083/jcb.79.1.121] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Cultures of dissociated rat superior cervical ganglion neurons (SCGN) were treated with the sympatholytic agent, guanethidine. When treated within the first couple of weeks in vitro, the neurons were rapidly destroyed. The cells grew less susceptible to the toxic effects of guanethidine with age in vitro. Moreover, the apparent affinity, Km, of the transport molecule for norepinephrine (NE) and guanethidine remained essentially unchanged between 2 and 7 wk in culture, as did the maximum velocity of transport (Vmax). This is at a time when previous studies have shown these neurons to be using acetylcholine (ACh) as their neurotransmitter. Cultures which were grown without supporting cells and from which cholinergic synaptic interactions were recorded physiologically were processed for autoradiography after incubation with [3H]NE. All cell bodies and processes seen had silver grains accumulated over them. These experiments show that sympathetic neurons in vitro maintain their amine uptake system relatively unchanged, even though they use ACh as their transmitter. The implications of these findings are discussed.
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Lennane RJ, Peart WS, Shaw J. Adrenergic influences on the electrical potential across the colonic mucosa of the rabbit. J Physiol 1975; 250:367-72. [PMID: 240933 PMCID: PMC1348366 DOI: 10.1113/jphysiol.1975.sp011059] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
1. An investigation was undertaken of the role of adrenergic influences on the transient change in colonic potential difference (p.d.) induced by handling in the rabbit. 2. P.d. was increased from 9-5 +/- 0-5 to 27-05 +/- 1-94 mV during a 2 hr period of handling and wrapping. Atropine and alpha-adrenergic block during this 2 hr period did not alter the magnitude of the response and the response in adrenalectomized animals was not significantly different from that of normal animals. 3. 'Total' adrenergic block and selective beta-adrenergic block abolished the change in p.d. with handling and infusion of an alpha-receptor agonist during the 2 hr period significantly reduced the response. 4. The changes in colonic p.d. with handling were greatly increased by the infusion of a beta-receptor agonist during the 2 hr test period. 5. The results indicate that the change in colonic p.d. with handling is a direct effect of the autonomic nervous system mediated via beta-receptors and that the changes were not related to the effects of circulating catecholamines or to changes in aldosterone production.
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Abstract
Abstract
A rapid and convenient method is described for the determination of methyldopa in pharmaceutical preparations. This is based on measuring the intensity of the orange colour, developed on reacting methyldopa with thiosemicarbazide in alkaline medium, at 490 nm. The colour obeys Beer’s law in a concentration range of 2·0-10 μ-g ml−1. Since the catecholic function with free adjacent positions is required for the development of the colour, the method is highly specific.
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McCulloch MW, Rand MJ, Story DF. Resting and stimulation-induced efflux of tritium from guinea-pig atria incubated with 3-H-noradrenaline. Clin Exp Pharmacol Physiol 1974; 1:275-89. [PMID: 4458999 DOI: 10.1111/j.1440-1681.1974.tb00550.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Abbs ET, Dodd MG. The relation between the adrenergic neurone-blocking and noradrenaline-depleting actions of some guanidine derivatives. Br J Pharmacol 1974; 51:237-47. [PMID: 4451743 PMCID: PMC1776754 DOI: 10.1111/j.1476-5381.1974.tb09653.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
1 The effects of some guanidine derivatives, (-)-N-(1-phenylethyl) guanidine (PEG), guanethidine and debrisoquine have been investigated on the content and subcellular distribution of noradrenaline in cat spleen and on the overflow of noradrenaline from this organ during stimulation of the splenic nerve.2 PEG and guanethidine, at a dose of 5 mg/kg, produced adrenergic neurone blockade within 15 min and the same dose of debrisoquine produced blockade within 30 minutes.3 All three compounds produced a decrease of similar magnitude in the noradrenaline content of the high-speed particulate (P(2)) and supernatant (S) fractions of splenic homogenates; these actions were temporally correlated with the adrenergic neurone-blocking action of the compounds.4 PEG did not produce any further decrease in the noradrenaline content of the subcellular fractions at times up to 18 h after its administration; adrenergic neurone blockade was maintained throughout this period but had disappeared after 7 days when the noradrenaline content of the subcellular fractions was restored to control levels.5 Guanethidine, in contrast, caused a marked progressive loss of the transmitter from all subcellular fractions-an effect which was maximal 18 h after its administration but continued, as did the adrenergic neurone-blocking action, for at least 72 hours. This additional loss of noradrenaline, over and above that seen after 15 min, is unlikely to be connected with the adrenergic neurone-blocking action of the drug.6 Dexamphetamine both prevented and antagonized the neurone blockade and the subcellular noradrenaline-depleting action of PEG and guanethidine. The restoration of nerve function after administration of dexamphetamine to animals pretreated with 5 mg/kg of either of these compounds was temporally correlated with a selective repletion of the noradrenaline content of the supernatant fraction of the spleen.7 Larger doses (15 mg/kg) of PEG or guanethidine produced a selective depletion of noradrenaline in only the supernatant fraction of the spleen. This depletion was temporally correlated with the adrenergic neurone-blocking action of these compounds. The lack of effect of the compounds at this dose level on the noradrenaline contained in the P(2) fraction may be due to ;stabilization' of the store of noradrenaline in vivo which gives rise to this fraction on homogenization.8 It is suggested that the guanidine-type adrenergic neurone-blocking agents displace the noradrenaline which is readily available for release by nerve impulses, and that it is this action that may account for their sympathomimetic properties.9 The ability of these guanidines to impair the release of noradrenaline by nerve impulses could occur because whilst they are present within the neurone the ;nerve-releasable store', which may in these experiments appear in the supernatant fraction after homogenization, may be unable to refill with transmitter.
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Miletich DJ, Ivankovic AD, Albrecht RF, Toyooka ET. The effect of emetine on myocardial catecholamine metabolism. J Pharm Pharmacol 1974; 26:101-4. [PMID: 4150823 DOI: 10.1111/j.2042-7158.1974.tb09232.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Abstract
The effects of emetine on the uptake and release of noradrenaline from the isolated, perfused, rat heart and on the in vivo myocardial retention of noradrenaline have been studied. Hearts were removed from animals under light ether anaesthesia, transferred to a modified Langendorff perfusing apparatus and perfused with Krebs-Ringer bicarbonate solution at a rate of 5 ml min−1. The effect of emetine on the uptake of noradrenaline was determined by perfusing hearts for a period of 6 min with perfusate containing various concentrations of emetine and 100 ng ml−1 of [14C]noradrenaline (14C-NA). After 6 min, the emetine-treated hearts contained less (±)−14C-NA than control hearts. The degree of reduction increased with increasing concentrations of emetine. The release of noradrenaline was determined after first perfusing hearts with 14C-NA followed by perfusion with solution containing emetine (0–01 mg ml−1) but free of labelled noradrenaline for periods of 10, 20 and 60 min. It was found that by 60 min emetine significantly decreased myocardial 14C-NA. In the intact animal myocardial concentrations of 14C-NA were reduced 90 min after intravenous 14C-NA, followed immediately by intraperitoneal emetine (1 mg kg−1). These results suggest that the cardiac arrhythmia and irritability seen after emetine treatment in man may be partly due to alterations in catecholamine metabolism.
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Abbs ET, Pycock CJ. The effects of bretylium on the subcellular distribution of noradrenaline and on adrenergic nerve function in rat heart. Br J Pharmacol 1973; 49:11-22. [PMID: 4787519 PMCID: PMC1776445 DOI: 10.1111/j.1476-5381.1973.tb08263.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
1. The effects of bretylium were investigated on the content and subcellular distribution of noradrenaline in the rat heart and on the response to stimulation of the sympathetic nerves supplying the heart.2. In most experiments bretylium produced no change in the total noradrenaline content of the heart but significant changes were produced in the subcellular distribution of noradrenaline.3. Treatment with amphetamine both prevented and antagonized the bretylium-induced adrenergic neurone blockade and most of the accompanying changes in the subcellular distribution of noradrenaline.4. There was a temporal correlation between the bretylium-induced depletion of noradrenaline from the microsomal (P(2)) fraction and adrenergic neurone blockade.5. The onset of adrenergic neurone blockade was also accompanied by an elevation of the noradrenaline content in the low-speed coarse (P(1A)) fraction and in the mitochondrial (P(1B)) fraction; this elevation was prevented by pretreatment with alpha-methyl-p-tyrosine.6. It is concluded that although the elevation of the noradrenaline content of the P(1A) and P(1B) fractions and a depletion of amine from the P(2) fraction are associated with the onset of adrenergic neurone blockade only the depletion from the P(2) fraction is required for its maintenance. This conclusion supports the hypothesis that only a small portion of the noradrenaline content of an adrenergically-innervated organ is associated with the release of transmitter, for when this small ;store' is depleted, by agents like bretylium, the nerves fail to function.
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Kalsner S. Effects of the inhibition of noradrenaline uptake and synthesis on the maintenance of the response to continuous nerve stimulation in the central artery of the rabbit ear. Br J Pharmacol 1972; 45:1-12. [PMID: 4402823 PMCID: PMC1666245 DOI: 10.1111/j.1476-5381.1972.tb09570.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
1. The central artery of the rabbit ear was perfused through its lumen in vitro, with a constant pressure technique, and stimulated continuously via its periarterial sympathetic nerves at the physiological frequency of 5 Hz.2. The vasoconstrictor response, which led initially to an almost complete cessation of intraluminal flow, deteriorated steadily over a period of hours. The involvement of presynaptic mechanisms in this effect was indicated by the finding that noradrenaline, administered extraluminally, produced a similar response before the onset of continuous stimulation and at a late stage when the constriction had decreased markedly. In addition, the noradrenaline precursor DOPA, restored the depressed responses towards their original values, indicating that failure involved depletion of mediator for release.3. Responses to continuous stimulation declined significantly faster after inhibition of tyrosine hydroxylase with alpha-methyl-p-tyrosine. However, inhibition of the uptake of noradrenaline with cocaine did not enhance the decline of the response, even when the sensitization produced by the compound was taken into account.4. It is concluded that synthesis, along with the mobilization of stored mediator, rather than uptake and re-use of noradrenaline maintain the effector response in the central artery of the rabbit ear stimulated continuously at a frequency within the physiological range.
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Clarke DE, Smookler HH, Barry H. Sympathetic nerve function and DOCA-NaCl induced hypertension. LIFE SCIENCES. PT. 1: PHYSIOLOGY AND PHARMACOLOGY 1970; 9:1097-108. [PMID: 5477379 DOI: 10.1016/0024-3205(70)90141-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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49
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Morgan DH, Oates JA, Shand DG. Evidence that guanethidine does not block adrenergic nerves by acting as a false transmitter. Br J Pharmacol 1970; 39:186P-187P. [PMID: 4315986 PMCID: PMC1702947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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Allen JD, Kofi JM, Shanks RG, Zaidi SA. The effect of experimental cardiac arrhythmias of a new anticonvulsant agent, Kö 1173, and its comparison with phenytoin and procainamide. Br J Pharmacol 1970; 39:183P-184P. [PMID: 4192640 PMCID: PMC1702975 DOI: 10.1111/j.1476-5381.1970.tb09568.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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