[Calcium antagonism of anisodamine on isolated rabbit thoracic aorta].
Anisodamine (Ani) or verapamil (Ver) relaxed the contracted thoracic aortic strips induced by CaCl2 and KCl in a noncompetitive manner with pD2' 3.6 and 5.8, respectively. Ani 50 mumol.L-1 and Ver 1 mumol.L-1 inhibited the intracellular Ca(2+)-dependent component of norepinephrine-induced contraction of aorta, but Ani 0.1 mmol.L-1 did not decrease the extracellular Ca(2+)-dependent component. In the presence of Ca2+, Ani 2.3 mumol.L-1 inhibited the proliferation of aortic smooth muscle cells. In the absence of Ca2+, the effect induced by Ani was biphasic-stimulatory at 2.3 mumol.L-1 concentrations and inhibitory at 61.7 mumol.L-1 concentrations. These results suggest that Ani, similar to Ver, mainly inhibits the potentially operated calcium channels.
Chen
J M
JM
Department of Pharmacology, Xuzhou Medical College, China.
Zhang
M Z
MZ
Gu
S L
SL
Zhang
G Y
GY
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D002118:Calcium / Q000037:antagonists & inhibitors*; D015220:Calcium Channels / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects*; D011817:Rabbits; D012991:Solanaceous Alkaloids / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology*; D014700:Verapamil / Q000494:pharmacology
D015220:Calcium Channels; D012991:Solanaceous Alkaloids; D014665:Vasodilator Agents; C003922:anisodamine; D014700:Verapamil; D002118:Calcium