Role of CGRP and GABA in the hypotensive effect of intrathecally administered anandamide to anesthetized rats

Cold atmospheric plasma treatment improves the γ-aminobutyric acid content of buckwheat seeds providing a new anti-hypertensive functional ingredient

Buckwheat (BW) is rich in γ-aminobutyric acid (GABA), which has great potential as a functional anti-hypertensive food ingredient. This study utilized cold atmospheric plasma (CAP) to promote GABA accumulation in BW during germination. The effect of this approach on GABA enrichment and anti-hypertensive activity of BW along with its processing properties were investigated. The results indicated that CAP stress treatment (50 W for 40 s) of BW seeds followed by germination at 30 °C for 60 h resulted in a GABA content of 2.22 ± 0.06 mg/g, which was a 2.64-fold greater than that of pristine BW. Cracking of the seed coat, faster germination, and the activation of glutamate decarboxylase might be responsible for the GABA enrichment. Compared with pristine BW, the GABA-enriched BW powder showed a greater inhibitory effect on the angiotensin-converting enzyme, an increased degree of pre-gelatinization and elasticity when it was formed into a dough.

Argentinean Society of Experimental Pharmacology: Brief history and main scientific contributions to the discipline

Argentina Biomedical Science has been historically strong. The development of Human and Veterinary Pharmacology in our country as a pivotal discipline has been acknowledged worldwide because of the quality of its contributions. Argentinean Society of Experimental Pharmacology (SAFE) is a non- profit association whose research fields include Experimental and Clinical Pharmacology. SAFE main goals are described as follow (a) To meet active researchers for studying concerns regarding Experimental and Clinical Pharmacology (b) To launch an initiative for development of the discipline in mainly our country and other collaborative countries worldwide (c) To spread the pharmacological know-how obtained from different research teams (d) To strengthen relations between pharmacologists (e) To facilitate the presentation and discussion of scientific papers. This current article shows the SAFE's more important scientific contribution to pharmacology through its former research scientists to the present.

The hypotensive effect of intrathecally injected (m)VD-hemopressin(α) in urethane-anesthetized rats

Previous studies suggest that cannabinoids system plays an important role in cardiovascular regulation. (m)VD-hemopressin(α) (VD-Hpα), an 11-residue peptide originating from the α1 chain of hemoglobin, was recently reported as a selective agonist of cannabinoid CB1 receptor. The present study was undertaken to investigate the intrathecal (i.t.) action of (m)VD-Hpα on blood pressure in urethane-anesthetized rats. Our results demonstrated that injections of (m)VD-Hpα (5-30 nmol, i.t.) produced a dose-dependent decrease in mean arterial pressure (MAP), similar to that of the non-peptidic cannabinoid receptor agonist WIN55212-2 (1.25-10 nmol, i.t.). The hypotensive effect of (m)VD-Hpα was not influenced by the CB1 receptor antagonist AM251 (20 nmol, i.t.) or the CB2 receptor antagonist AM630 (20 nmol, i.t.). However, WIN55212-2-induced hypotension was almost completely prevented by i.t. administration of AM251, not by AM630. The spinal hypotension of (m)VD-Hpα and WIN55212-2 was significantly reduced by pretreatment with the α-adrenoceptor antagonist phentolamine (1 mg/kg, i.v.), but not by the β-adrenoceptor antagonist propranolol (2 mg/kg, i.v.) or the muscarinic receptor antagonist atropine (2 mg/kg, i.v.). In addition, L-NAME (50 mg/kg, i.v.), the inhibitor of nitric oxide (NO) synthase, significantly reduced WIN55212-2-induced hypotension, but had no effect on the hypotensive response to (m)VD-Hpα. Collectively, the results show that i.t. administration of (m)VD-Hpα induces a decrease in MAP via a non-CB1 and non-CB2 mechanism.

The role of TRPV1 receptors in the antinociceptive effect of anandamide at spinal level

While it is well known that the endogenous cannabinoid receptor ligand anandamide also activates the transient receptor potential vanilloid1 (TRPV1) receptors, there has been no in vivo study indicating the role of the TRPV1 receptors in the antinociceptive effect of anandamide at spinal level. The goal of this study was to determine the effect of inhibition of TRPV1 receptors by capsazepine on the antinociceptive potency of anandamide after intrathecal administration. Anandamide alone (1, 30 or 100 microg) dose-dependently decreased carrageenan-induced thermal hyperalgesia, however, the highest dose caused temporary excitation and vocalization, suggesting the pain-inducing potential of anandamide. Capsazepine (10 or 20 microg) by itself did not change the pain sensitivity markedly, but the lower dose increased it, and the higher dose decreased the antinociceptive effect of 30 microg anandamide. Furthermore, both doses of capsazepine decreased the efficacy of the largest dose of anandamide. These results show that TRPV1 receptor activation plays a substantial role in the antinociceptive effects of anandamide at spinal level. The effect of the inhibition on TRPV1 receptors depended on the dose applied. We presume that coactivation of the cannabinoid and TRPV1 receptors by anandamide provides elevated antinociception through the release of antinociceptive endogenous ligands at spinal level.

Cannabinoids as therapeutic agents in cardiovascular disease: a tale of passions and illusions

In addition to their classical known effects, such as analgesia, impairment of cognition and learning and appetite enhancement, cannabinoids have also been related to the regulation of cardiovascular responses and implicated in cardiovascular pathology. Elevated levels of endocannabinoids have been related to the extreme hypotension associated with various forms of shock as well as to the cardiovascular abnormalities that accompany cirrhosis. In contrast, cannabinoids have also been associated with beneficial effects on the cardiovascular system, such as a protective role in atherosclerosis progression and in cerebral and myocardial ischaemia. In addition, it has also been suggested that the pharmacological manipulation of the endocannabinoid system may offer a novel approach to antihypertensive therapy. During the last decades, the tremendous increase in the understanding of the molecular basis of cannabinoid activity has encouraged many pharmaceutical companies to develop more potent synthetic cannabinoid analogues and antagonists, leading to an explosion of basic research and clinical trials. Consequently. not only the synthetic THC dronabinol (Marinol) and the synthetic THC analogue nabilone (Cesamet) have been approved in the United States, but also the standardized cannabis extract (Sativex) in Canada. At least three strategies can be foreseen in the future clinical use of cannabinoid-based drugs: (a) the use of CB(1) receptor antagonists, such as the recently approved rimonabant (b) the use of CB(2)-selective agonists, and (c) the use of inhibitors of endocannabinoid degradation. In this context, the present review examines the effects of cannabinoids and of the pharmacological manipulation of the endocannabinoid system, in cardiovascular pathophysiology.