4-(3-3-4-p-menthadien-(1-8)-yl)olivetol and anandamide

Recent studies suggest that endocannabinoid signaling is modulated by 17β-estradiol (17Eβ) however it is unclear if this applies to the cardiovascular actions of anandamide, a major endocannabinoid. This study examined the in vitro effects of 17Eβ on vasorelaxation to anandamide in myograph-mounted small mesenteric arteries obtained from Wistar rats and Spontaneously Hypertensive Rats (SHRs) of both sexes. Treatment with 1μM 17Eβ but not its enantiomer 17Eα significantly enhanced relaxation to anandamide in male Wistar rats. This effect was independent of a functional endothelium but was blocked by the Transient Receptor Potential Vanilloid type 1 (TRPV1) receptor antagonist SB366791 (2μM) or prolonged treatment with the TRPV1 agonist capsaicin (10μM). A TRPV1-dependent potentiation by 17Eβ was also observed in male SHRs, but not in female Wistar rats or female SHRs. Whilst inhibition of anandamide hydrolysis by 1μM URB597 (an inhibitor of fatty acid amide hydrolase; FAAH) similarly augmented anandamide relaxation in male, but not female, Wistar rats and SHRs, URB597 did not affect the 17Eβ-induced potentiation. Female SHRs displayed a larger maximal relaxation to anandamide; however sex difference was not found in Wistar rats. We conclude that pharmacological levels of 17Eβ potentiate mesenteric relaxation to anandamide through mechanisms dependent on TRPV1 receptors but not FAAH-mediated hydrolysis in male Wistar rats and male SHRs. Sexual dimorphism was observed in the modulatory effects of 17Eβ and URB597, which does not necessarily lead to a greater anandamide response in female rats.

Topics: Amidohydrolases; Animals; Arachidonic Acids; Blood Pressure; Capsaicin; Dose-Response Relationship, Drug; Endocannabinoids; Estradiol; Female; Hypertension; In Vitro Techniques; Male; Mesenteric Arteries; Polyunsaturated Alkamides; Rats; Rats, Wistar; Resorcinols; TRPV Cation Channels; Vasodilation

We have previously shown that the endocannabinoid anandamide and its metabolically stable analog (R)-methanandamide produce vasorelaxation in rabbit aortic ring preparations in an endothelium-dependent manner that could not be mimicked by other CB(1) cannabinoid receptor agonists (Am J Physiol 282: H2046-H2054, 2002). Here, we show that (R)-methanandamide and abnormal cannabidiol stimulated nitric oxide (NO) production in rabbit aortic endothelial cells (RAEC) in a dose-dependent manner but that other CB(1) and CB(2) receptor agonists, such as cis-3R-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]-trans-4R-3(3-hydroxypropyl)-1R-cyclohexanol (CP55940) and (R)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl) pyrrolo-[1,2,3-d,e]-1,4-benzoxazin-6-yl]-1-naphthalenyl-methanone (WIN55212-2), failed to do so. CB(1) antagonists rimonabant [also known as SR141716; N-piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide] and 6-methoxy-2-(4-methoxyphenyl)benzo[b]-thien-3-yl][4-cyanophenyl]methanone (LY320135) and CB(2) antagonist N-[(1S)-endo-1,3,3,-trimethylbicyclo[2.2.1]heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide (SR144528) failed to block (R)-methanandamide-mediated NO production in RAEC. However, anandamide receptor antagonist (-)-4-(3-3,4-trans-p-menthadien-(1,8)-yl)-orcinol (O-1918) blocked (R)-methanandamide-mediated NO production in RAEC. Reverse transcriptase-polymerase chain reaction and Western blot analyses failed to detect the CB(1) receptor in RAEC, making this a good model to study non-CB(1) responses to anandamide. (R)-Methanandamide produced endothelial nitric-oxide synthase (eNOS) phosphorylation via the activation of phosphoinositide 3-kinase-Akt signaling. Inhibition of G(i) signaling with pertussis toxin, or phosphatidylinositol 3-kinase activity with 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002), resulted in a decrease in (R)-methanandamide-induced Akt phosphorylation and NO production. Results from this study suggest that in RAEC, (R)-methanandamide acts on a novel non-CB(1) and non-CB(2) anandamide receptor and signals through G(i) and phosphatidylinositol 3-kinase, leading to Akt activation, eNOS phosphorylation, and NO production.

Topics: Animals; Arachidonic Acids; Benzofurans; Benzoxazines; Camphanes; Cannabinoid Receptor Modulators; Cells, Cultured; Chromones; Cyclohexanols; Dose-Response Relationship, Drug; Endocannabinoids; Endothelial Cells; Enzyme Inhibitors; GTP-Binding Protein alpha Subunits, Gi-Go; Morpholines; Naphthalenes; Nitric Oxide; Pertussis Toxin; Phosphoinositide-3 Kinase Inhibitors; Phosphorylation; Piperidines; Polyunsaturated Alkamides; Proto-Oncogene Proteins c-akt; Pyrazoles; Rabbits; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Resorcinols; Rimonabant; Signal Transduction

Topics: Arachidonic Acids; Endocannabinoids; Endothelium, Vascular; Humans; Hypertension, Pulmonary; Polyunsaturated Alkamides; Pulmonary Artery; Receptors, Cannabinoid; Resorcinols; Vasodilation

The endocannabinoid anandamide is implicated in the pathogenesis of hypotension in haemorrhagic, endotoxic, and cardiogenic shock. It has been demonstrated in animal, but not in human, vessels that the vasodilatory effects of anandamide and abnormal cannabidiol are partially mediated by an as yet unidentified endothelial cannabinoid receptor. Our study was performed to examine the influence of abnormal cannabidiol on the human pulmonary artery.. Isolated human pulmonary arteries were obtained from patients without clinical evidence of pulmonary hypertension during resection of lung carcinoma. Vasodilatory effects of abnormal cannabidiol were examined on endothelium-intact vessels preconstricted with serotonin or potassium chloride.. Anandamide and abnormal cannabidiol relaxed serotonin-preconstricted vessels concentration-dependently. The effect of abnormal cannabidiol was reduced by endothelium denudation, pertussis toxin and two antagonists of the novel endothelial receptor, cannabidiol and O-1918, but not by the nitric oxide synthase inhibitor L-NAME given together with the cyclooxygenase inhibitor indomethacin. It was also diminished by blockade of calcium-activated potassium channels by the nonselective blocker tetraethylammonium or by combination of selective blockers of small (apamin) and intermediate and large (charybdotoxin) conductance calcium-activated potassium channels. The potency of abnormal cannabidiol to relax vessels was lower in potassium chloride than in serotonin-preconstriced preparations.. Abnormal cannabidiol relaxes human pulmonary arteries in an endothelium-independent and endothelium-dependent manner. The latter component is probably mediated via the putative endothelial cannabinoid receptor, activation of which may release endothelium-derived hyperpolarizing factor, which in turn acts via calcium-activated potassium channels. Abnormal cannabidiol is behaviourally inactive; it may have a therapeutic implication in vascular diseases, especially in the treatment of pulmonary hypertension.

Topics: Arachidonic Acids; Dose-Response Relationship, Drug; Endocannabinoids; Endothelium, Vascular; Female; Humans; In Vitro Techniques; Indomethacin; Male; Middle Aged; NG-Nitroarginine Methyl Ester; Pertussis Toxin; Polyunsaturated Alkamides; Potassium Channel Blockers; Potassium Chloride; Pulmonary Artery; Receptors, Cannabinoid; Resorcinols; Serotonin; Vasodilation

Cannabidiol has been reported to be a neuroprotectant, but the neuroprotective mechanism of cannabidiol remains unclear. We studied the neuroprotective mechanism of cannabidiol in 4-hour middle cerebral artery (MCA) occlusion mice.. Male MCA occluded mice were treated with cannabidiol, abnormal cannabidiol, anandamide, methanandamide, cannabidiol plus capsazepine, and cannabidiol plus WAY100135 before and 3 hours after MCA occlusion. The infarct size was determined after 24 hours (2,3,5-triphenyltetrazolium chloride staining). Cerebral blood flow (CBF) was measured at, before and 1, 2, 3, and 4 hours after MCA occlusion.. Cannabidiol significantly reduced the infarct volume induced by MCA occlusion in a bell-shaped curve. Similarly, abnormal cannabidiol but not anandamide or methanandamide reduced the infarct volume. Moreover, the neuroprotective effect of cannabidiol was inhibited by WAY100135, a serotonin 5-hydroxytriptamine1A (5-HT1A) receptor antagonist but not capsazepine a vanilloid receptor antagonist. Cannabidiol increased CBF to the cortex, and the CBF was partly inhibited by WAY100135 in mice subjected to MCA occlusion.. Cannabidiol and abnormal cannabidiol reduced the infarct volume. Furthermore, the neuroprotective effect of cannabidiol was inhibited by WAY100135 but not capsazepine, and the CBF increased by cannabidiol was partially reversed by WAY100135. These results suggested that the neuroprotective effect of cannabidiol may be related to the increase in CBF through the serotonergic 5-HT1A receptor.

Topics: Animals; Arachidonic Acids; Cannabidiol; Cerebral Infarction; Cerebrovascular Circulation; Endocannabinoids; Infarction, Middle Cerebral Artery; Male; Mice; Neuroprotective Agents; Piperazines; Polyunsaturated Alkamides; Receptor, Serotonin, 5-HT1A; Resorcinols; Serotonin 5-HT1 Receptor Antagonists; Serotonin Antagonists