TY - JOUR
T1 - Mechanism of the vasodilator action of calcitonin gene‐related peptide in conscious rats
AU - Abdelrahman, Aly
AU - Wang, Yong‐Xiang ‐X
AU - Chang, Sylvia Diana
AU - Pang, Catherine C.Y.
PY - 1992/5
Y1 - 1992/5
N2 - The aim of this study was to investigate whether the hypotensive effect of rat α‐calcitonin gene‐related peptide (αCGRP) in conscious rats is mediated by endothelium‐derived nitric oxide (NO) or the opening of adenosine 5′‐triphosphate (ATP)‐sensitive potassium (KATP) channels. Dose‐mean arterial pressure (MAP)‐response curves of αCGRP were examined in the presence of vehicle, phenylephrine, KATP channel antagonist glibenclamide or NO synthase inhibitors, NG‐nitro‐l‐arginine methyl ester (l‐NAME) and NG‐nitro‐d‐arginine methyl ester (d‐NAME). Dose‐MAP‐response curves for sodium nitroprusside were also constructed in the presence and absence of l‐NAME and d‐NAME. αCGRP and nitroprusside produced dose‐dependent reductions in MAP which were potentiated by phenylephrine. Both l‐NAME and d‐NAME attenuated the depressor response to αCGRP but not nitroprusside. Dose‐MAP‐response curves for pinacidil, a KATP‐channel activator, were also examined in the presence of glibenclamide or vehicle. Glibenclamide attenuated pinacidil‐ but not αCGRP‐induced reductions in MAP. It is concluded that the hypotensive effects of αCGRP are partially mediated via endothelium‐derived NO but not via the opening of KATP channels. 1992 British Pharmacological Society
AB - The aim of this study was to investigate whether the hypotensive effect of rat α‐calcitonin gene‐related peptide (αCGRP) in conscious rats is mediated by endothelium‐derived nitric oxide (NO) or the opening of adenosine 5′‐triphosphate (ATP)‐sensitive potassium (KATP) channels. Dose‐mean arterial pressure (MAP)‐response curves of αCGRP were examined in the presence of vehicle, phenylephrine, KATP channel antagonist glibenclamide or NO synthase inhibitors, NG‐nitro‐l‐arginine methyl ester (l‐NAME) and NG‐nitro‐d‐arginine methyl ester (d‐NAME). Dose‐MAP‐response curves for sodium nitroprusside were also constructed in the presence and absence of l‐NAME and d‐NAME. αCGRP and nitroprusside produced dose‐dependent reductions in MAP which were potentiated by phenylephrine. Both l‐NAME and d‐NAME attenuated the depressor response to αCGRP but not nitroprusside. Dose‐MAP‐response curves for pinacidil, a KATP‐channel activator, were also examined in the presence of glibenclamide or vehicle. Glibenclamide attenuated pinacidil‐ but not αCGRP‐induced reductions in MAP. It is concluded that the hypotensive effects of αCGRP are partially mediated via endothelium‐derived NO but not via the opening of KATP channels. 1992 British Pharmacological Society
KW - Calcitonin gene‐related peptide (CGRP)
KW - K channel
KW - N‐nitro‐d‐arginine methyl ester (d‐NAME)
KW - N‐nitro‐l‐arginine methyl ester (l‐NAME)
KW - glibenclamide
KW - nitric oxide synthase inhibitor
KW - nitroprusside
KW - pinacidil
UR - http://www.scopus.com/inward/record.url?scp=0026511037&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0026511037&partnerID=8YFLogxK
U2 - 10.1111/j.1476-5381.1992.tb14290.x
DO - 10.1111/j.1476-5381.1992.tb14290.x
M3 - Article
C2 - 1504730
AN - SCOPUS:0026511037
SN - 0007-1188
VL - 106
SP - 45
EP - 48
JO - British Journal of Pharmacology
JF - British Journal of Pharmacology
IS - 1
ER -