Vasomotor Effects of Acetylcholine, Bradykinin, Noradrenaline,5-Hydroxytryptamine, Histamine and Angiotensin II on the Mouse BasilarArtery

[摘要] References(34)Cited-By(2)We investigated theresponsiveness of the mouse basilar artery to acetylcholine (ACh), bradykinin (BK),noradrenaline (NA), 5-hydroxytryptamine (5-HT), histamine (His) and angiotensin (Ang) IIin order to characterize the related receptor subtypes in vitro. ACh andBK induced endothelium-dependent relaxation of precontracted arteries with U-46619 (athromboxane A2 analogue). Atropine (a non-selective muscarinic receptorantagonist) and Nω-nitro-L-arginine (a NO synthase inhibitor, L-NNA)shifted the concentration-response curve for ACh to the right, whereas pirenzepine,methoctramine and pFHHSiD (muscarinic M1, M2 and M3antagonists, respectively) had no significant effect. L-NNA and HOE140 (a B2antagonist) shifted the concentration-response curve for BK to the right, whereasdes-Arg9-[Leu8]-BK (a B1 antagonist) and indomethacin(a cyclooxygenase inhibitor) had no significant effect. NA failed to produce any vasomotoraction. His and Ang II induced concentration-dependent contraction. Diphenhydramine (aH1 antagonist) shifted the concentration-response curve for His to the right,whereas cimetidine (a H2 antagonist) had no significant effect. Losartan (anAT1 antagonist) shifted the concentration-response curve for Ang II to theright, whereas PD123319 (an AT2 antagonist) had no significant effect. Theseresults suggest that the H1 and AT1 receptor subtypes might play animportant role in arterial contraction, whereas muscarinic receptor subtypes apart fromM1, M2 and M3, and B2 receptors on theendothelium, might modify these contractions to relaxations.

[学科分类] 兽医学

[关键词] cerebral artery;pA2;receptor subtype;vasoconstrictor;vasodilator