Assessing mixed anxiety-depressive disorder. A national primary care survey

Prevalence and risk factors associated with mixed anxiety-depressive disorder (MAD) have yet to be established. Using MINI 5.0.1 and HADS, a two-week survey involving 21,644 primary care patients was carried out. We found 1.8% of subjects with MAD and 20% of subjects with a co-morbid anxiety and depression (CAD) disorder. MAD patients without a past history of anxiety/affective episodes were defined as "pure MAD" (pMAD: 0.9% of the sample). While MAD patients showed a number of differences vs. the other groups of patients in the socio-demographic statistics, pMAD patients were not different, apart from a higher proportion of males vs. CAD patients. Nearly in all the comparisons, MAD and pMAD patients showed lower association with life events and with a familial predisposition than the other patients. On HADS assessment, MAD showed a higher risk of anxiety and depressive symptoms than anxiety diagnoses, a lower risk of depressive symptoms than depressive diagnoses and a lower risk of both anxiety and depressive symptoms than CAD. Since more than a half of MAD patients were classified as pMAD, the hypothesis that MAD should be viewed as a partial remission of a major depression is not entirely confirmed in our study.

Headache and anxiety-depressive disorder comorbidity: the HADAS study

Psychiatric comorbidity (prevalence and types) was tested in a naturalistic sample of adult patients with pure migraine without aura, and in two control groups of patients, one experiencing pure tension-type headache and the other combined migraine and tension-type headaches. The study population included 374 patients (158, 110 and 106) from nine Italian secondary and tertiary centres. Psychiatric comorbidity was recorded through structured interview and also screened with the Mini International Neuropsychiatry Interview (MINI). Only anxiety and depression were investigated. Psychiatric disorders were reported by 49 patients (14.6%; 10.9% of patients with migraine, 12.8% of those with tension-type headache and 21.4% of those with combined migraine and tension-type headaches). The MINI interview detected a depressive episode in 59.9% of patients with migraine, 68.3% of patients with tension-type headache and 69.6% of patients with combined migraine and tension-type headaches. Depression subtypes were significantly different across groups (p=0.03). Anxiety (mostly generalised) was reported by 18.4% of patients with migraine, 19.3% of patients with tension-type headache, and 18.4% of patients with combined migraine and tension-type headaches. The values for panic disturbance were 12.7, 5.5 and 14.2, and those for obsessive-compulsive disorders were 2.3, 1.1 and 9.4% (p=0.009). Based on these results, psychopathology of primary headache can be a reflection of the burden of the disease rather than a hallmark of a specific headache category.

Chiral tetrahydroquinoline derivatives as potent anti-hyperalgesic agents in animal models of sustained inflammation and chronic neuropathic pain

Chiral tetrahydroquinoline derivatives have been prepared by an asymmetric Mannich-type condensation reaction using commercially available vinyloxyethylsilane and a N-arylimino R-(+)-t-butyl lactate ester, in the presence of a catalytic amount of metal triflates as Lewis acids. This synthetic approach gave rise to the target aldehyde intermediate in moderate facial diastereoselectivity and in high chemical yield. This efficient route enabled to scale up the synthesis of an orally bioavailable glycine antagonist showing outstanding in vivo anti-hyperalgesic activity in different animal models of sustained inflammation and chronic neuropathic pain.

Synthesis and pharmacological characterisation of 2,4-dicarboxy-pyrroles as selective non-competitive mGluR1 antagonists

Metabotropic glutamate receptors (mGluRs) are an unusual family of G-protein coupled receptor (GPCR), and are characterised by a large extracellular N-terminal domain that contains the glutamate binding site. We have identified a new class of non-competitive metabotropic glutamate receptor 1 (mGluR1) antagonists, 2,4-dicarboxy-pyrroles which are endowed with nanomolar potency. They interact within the 7 transmembrane (7TM) domain of the receptor and show antinociceptive properties when tested in a number of different animal models.

GV196771A, an NMDA receptor/glycine site antagonist, attenuates mechanical allodynia in neuropathic rats and reduces tolerance induced by morphine in mice

The effects of the N-methyl-D-aspartate (NMDA) receptor/glycine site antagonist, GV196771A (E-4,6-dichloro-3-(2-oxo-1-phenyl-pyrrolidin-3-ylidenemethyl)-1H-indole-2-carboxylic acid sodium salt), on mechanical allodynia and on tolerance to the antinociceptive effects induced by morphine were evaluated. Its antiallodynic properties were studied in a model of chronic constriction injury applied to rat sciatic nerve. GV196771A (0.3-10 mg/kg, p.o.) dose-dependently inhibited established mechanical allodynia when tested 14 or 21 days after nerve ligation. In the formalin test in mice, GV196771A (10 or 20 mg/kg, p.o.), administered for 8 days together with morphine 10 mg/kg, i.p. inhibited morphine tolerance development in both early and late phases of the test. This finding reinforces the key role of the NMDA receptors in the plastic event, such as allodynia, which develops in some conditions of painful neuropathy. Moreover, the capability to strongly reduce morphine-induced tolerance suggests that GV196771A could be an alternative agent for the treatment of difficult pain states not only when given alone, but also in combination, in order to prolong the analgesic effects of the opiates.

The calcium-channel blocker lacidipine reduces the development of atherosclerotic lesions in the apoE-deficient mouse

BACKGROUND

Lacidipine is a widely used calcium-channel blocker, which has both long-lasting antihypertensive activity and also antioxidant properties. Previous studies have demonstrated the ability of lacidipine to reduce the development of atherosclerotic lesions in several animal models.

OBJECTIVE

The present study investigated the antiatherosclerotic potential of lacidipine in the apoE-deficient mouse, an experimental model of atherosclerosis showing progressively complex and widespread lesions which closely resemble the inflammatory-fibrous plaques seen in humans.

METHODS

Lacidipine was administered daily by gavage for 10 weeks at dose levels of 0 (control), 0.3, 1.0 and 3.0 mg/kg.

RESULTS

Lacidipine administration reduces the extension of atherosclerotic lesions in the aorta of the apoE-deficient mouse without affecting plasma lipid levels. We also show that apoE-deficient mice have four-fold higher values of the proatherogenic peptide, endothelin, compared with the wild-type C57BL/6 mouse and that lacidipine administration reduced, in a dose-dependent manner, the concentrations of plasma endothelin.

CONCLUSION

Lacidipine has anti-atherogenic effects in the apoE-deficient mouse, and reduces plasma endothelin concentrations.

Modulation of nociceptive transmission by NMDA/glycine site receptor in the ventroposterolateral nucleus of the thalamus

NMDA-type glutamate receptors are involved in the generation and maintenance of altered pain states. In the present study, we examined the effect of an NMDA-glycine site antagonist, GV196771A [E-4, 6-dichloro-3-(2-oxo-1-phenyl-pyrrolidin-3-ylidenemethyl)-1H- indole-2- carboxylic acid sodium salt], on responses to noxious stimuli both in normal rats and during peripheral mononeuropathy induced by chronic constriction injury (CCI) of the sciatic nerve. In one series of experiments, activity of nociceptive neurons in the ventroposterolateral (VPL) nucleus of the thalamus was recorded in response to pressure stimuli to the contralateral hindpaw. Intravenous injection (iv) of the glycine antagonist had no effect on these cells in normal rats. When tested in rats with CCI induced 2-3 weeks previously, however, GV196771A (0.125, 0.5 and 2.0mg/kg) blocked responses to noxious stimulation in a dose-dependent and reversible manner. Morphine (0.5mg/kg, iv) and the NMDA channel blocker MK801 (0.1mg/kg, iv) suppressed noxious stimulus-evoked activity of VPL neurons in both normal and CCI-treated rats. MK801 also decreased the responses of non-nociceptive neurons to brush stimulation in both sets of animals, in contrast to the glycine antagonist which did not alter the responses of these cells. Similar results were obtained from a series of behavior experiments in which the latency for paw withdrawal from heat stimulation was measured in normal and CCI-treated rats. GV196771A (3 and 10mg/kg) injected orally, reduced the hyperalgesic response in the treated rats but did not change the withdrawal latency in normal rats. Taken together, these findings suggest that block of the NMDA receptor decreases nociceptive transmission in the thalamus and can modulate hyperalgesic states. GV196771A and glycine antagonists in general may represent innovative and safe agents for the treatment of neuropathic pain.

Extracellular matrix gene expression in the left ventricular tissue of spontaneously hypertensive rats

The aim of this study was to investigate the extracellular matrix gene expression in the hypertrophied left ventricular tissue of spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats, at early and mature ages. Interestingly, with age, a marked increase (+85% and +187% at 25 and 30 weeks of age, respectively, p < 0.01, vs 5 weeks) in matrix metalloproteinase-1 (MMP-1) mRNA levels in SHR and a progressive decrease (-50%, -70%, -78%, -70% at 10, 15, 25 and 30 weeks, respectively, p < 0.01, vs 5 weeks) in WKY were seen. Moreover, mRNA levels were significantly lower in SHR at 5 weeks. The analysis of mRNA expression for the tissue inhibitor of metalloproteinase-1 (TIMP-1) showed a significant increase in WKY (+44% and +44%, vs 15 and 25 weeks, respectively, p < 0.05), whereas there were no significant changes in SHR with development. At 30 weeks TIMP-1 mRNA levels were significantly reduced in SHR. Temporal trends of procollagen alpha1(I) and procollagen alpha1(III) mRNA levels were similar in both strains, but lower levels for procollagen alpha1(III) were found in SHR at 5 and 30 weeks. Although no significant differences were measured between the strains, mRNA levels for fibronectin were found decreased in WKY and increased in SHR with age. The results of the present study suggest an altered balance between collagen deposition and collagen degradation with development in this model of left ventricular hypertrophy and hypertension.

Potent antihyperalgesic activity without tolerance produced by glycine site antagonist of N-methyl-D-aspartate receptor GV196771A

Central sensitization is a condition of enhanced excitability of spinal cord neurons that contributes to the exaggerated pain sensation associated with chronic tissue or nerve injury. N-methyl-D-aspartate (NMDA) receptors are thought to play a key role in central sensitization. We have tested this hypothesis by characterizing in vitro and in vivo a novel antagonist of the NMDA receptor acting on its glycine site, GV196771A. GV196771A exhibited an elevated affinity for the NMDA glycine binding site in rat cerebral cortex membranes (pKi = 7.56). Moreover, GV196771A competitively and potently antagonized the activation of NMDA receptors produced by glycine in the presence of NMDA in primary cultures of cortical, spinal, and hippocampal neurons (pKB = 7.46, 8. 04, and 7.86, respectively). In isolated baby rat spinal cords, 10 microM GV196771A depressed wind-up, an electrical correlate of central sensitization. The antihyperalgesic properties of GV196771A were studied in a model of chronic constriction injury (CCI) of the rat sciatic nerve and in the mice formalin test. In the CCI model GV196771A (3 mg/kg twice a day p.o.), administered before and then for 10 days after nerve ligature, blocked the development of thermal hyperalgesia. Moreover, GV196771A (1-10 mg/kg p.o.) reversed the hyperalgesia when tested after the establishment of the CCI-induced hyperalgesia. In the formalin test GV196771A (0.1-10 mg/kg p.o.) dose-dependently reduced the duration of the licking time of the late phase. These antihyperalgesic properties were not accompanied by development of tolerance. These observations strengthen the view that NMDA receptors play a key role in the events underlying plastic phenomena, including hyperalgesia. Moreover, antagonists of the NMDA glycine site receptor could represent a new analgesic class, effective in conditions not sensitive to classical opioids.

Structural changes of small resistance arteries in spontaneously hypertensive rats after treatment with various doses of lacidipine

OBJECTIVE

To evaluate the modifications of the morphology of mesenteric small resistance vessels in spontaneously hypertensive rats (SHR) induced by lacidipine treatment.

METHODS

Lacidipine was administered at three different dosages, 20, 10, and 0.3 mg/kg per day. Fifty rats were studied. Nine SHR and 11 Wistar-Kyoto (WKY) rats were not treated. Each lacidipine dose was administered to 10 SHR. The drug and the placebo were administered by gavage from age 4 to age 12 weeks. The blood pressure was measured noninvasively every week. The animals were killed when they were aged 13 weeks, and the relative left ventricular mass (left ventricular weight plus septum weight/body weight) was calculated. Small mesenteric resistance vessels were dissected and mounted on a micromyograph (Mulvany's technique), and morphological parameters of the vessels were studied (media thickness and media: lumen ratio).

RESULTS

The systolic blood pressure of SHR administered 20 and 10 mg/kg lacidipine per day was reduced significantly during the treatment period, whereas that of rats treated with 0.3 mg/kg lacidipine per day did not change. A significant reduction in media: lumen ratio was observed for all three groups of treated rats, including those to which 0.3 mg/kg lacidipine per day had been administered, and no reduction in systolic blood pressure could be detected. The relative left ventricular mass was reduced significantly only in rats to which 20 and 10 mg/kg lacidipine per day had been administered.

CONCLUSION

A significant reduction in magnitude of vascular structural alternations was observed even in SHR treated with a low, nonhypotensive dose of lacidipine.

Upregulation of spinal glutamate receptors in chronic pain

Recent studies indicate that glutamate binding to N-methyl-D-aspartate receptors in the spinal cord is involved in triggering the development of chronic pain However, the processes which directly underlie the increased pain remain unclear. Here we report that, following peripheral nerve injury (ligation of the sciatic nerve) in the rat, there is an increase in immunoreactive labelling of non-N-methyl-D-asparatate, AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazoleproprionate), glutamate receptors in the superficial laminae of the lumbar spinal cord ipsilateral to the ligation. The increase in AMPA receptor expression peaks 14 days after nerve ligation and decreases 35 days post-ligation, corresponding to the time-course of heightened sensitivity to mechanical and thermal noxious stimuli (hyperalgesia) induced by the ligation. Given evidence that AMPA receptors in the superficial laminae mediate fast nociceptive transmission in the spinal cord, our findings suggest that an upregulation of spinal AMPA receptors contributes to hyperalgesia following peripheral nerve injury.

Analysis of the interaction between lacidipine and BAY K 8644 in two isolated rabbit arteries

The calcium antagonist activity of the long-acting 1,4-dihydropyridine (DHP) lacidipine has been analyzed in rabbit ear artery (REA) and rabbit basilar artery (RBA). Its potency has been estimated from its interaction with BAY K 8644 using a three state gating model of the voltage-operated calcium channel. As a contractile agent, BAY K 8644 exhibited a bell-shaped concentration-response curve in both arteries. For fitting purposes, a second binding interaction between BAY K 8644 and the channel has been used to describe the descending part of the curve. The K(app)s for lacidipine and three other DHPs (nifedipine, nitrendipine and amlodipine) have been compared to pA2 values obtained from displacement of calcium concentration-response curves. In both REA and RBA the K(app)s for the four DHPs were not significantly different compared to their pA2s. The pK(app) values for lacidipine were estimated as 9.80 for REA and 10.20 for RBA.

The hemodynamic effects of lacidipine in anesthetized dogs: comparison with nitrendipine, amlodipine, verapamil, and diltiazem

The hemodynamic effects of lacidipine in anesthetized, open-chest dogs were compared with those of nitrendipine, amlodipine, verapamil and diltiazem. Lacidipine administered intravenously induced dose-related, long-lasting reductions in systemic and coronary vascular resistance with corresponding increases in aortic flow and coronary blood flow. The hypotensive effect (ED25 for mean blood pressure reduction = 0.006 mg/kg) was still significant 120 min after administration with all doses tested. Nitrendipine was equipotent with lacidipine in reducing the mean blood pressure (ED25 = 0.005 mg/kg), but its effect was shorter acting (significant effect at 120 min only with the highest dose tested). Amlodipine caused a marked and long-lasting hypotension though at higher doses than lacidipine (ED25 = 0.50 mg/kg). Short-lasting hypotensive responses were also detected with verapamil (ED25 = 0.1 mg/kg) and diltiazem (ED25 = 0.12 mg/kg). A reflex increase in heart rate was observed with lacidipine, nitrendipine, and amlodipine, whereas verapamil and diltiazem showed a dose-related bradycardia. No effect on AV conduction was observed with lacidipine and nitrendipine, whereas amlodipine, verapamil, and diltiazem produced second- to third-degree AV block at the highest doses tested. Lacidipine and nitrendipine caused a reflex increase in contractile index at all doses, whereas amlodipine was more similar to verapamil since a marked decrease in contractile index was detected at the highest dose. Diltiazem was practically devoid of negative inotropic effect.