Effects of adrenomedullin, calcitonin gene-related peptide, and amylin on cerebral circulation in dogs.
J Cereb Blood Flow Metab
; 15(5): 827-34, 1995 Sep.
Article
em En
| MEDLINE
| ID: mdl-7673375
ABSTRACT
The effect of human adrenomedullin on cerebral circulation was investigated in dogs in vivo and in vitro. Bolus administration of adrenomedullin or its homologous peptides, calcitonin gene-related peptide (CGRP) and amylin, into the vertebral artery induced a dose-dependent increase in vertebral blood flow. The potencies of adrenomedullin and CGRP were similar and approximately 100 times more than that of amylin. The effects of adrenomedullin and CGRP were inhibited by CGRP8-37, an antagonist of CGRP. In contrast to substance P, adrenomedullin did not induce an increase in blood flow after prior administration of CGRP. Pretreatment with either NG-nitro-L-arginine methyl ester or indomethacin did not affect the adrenomedullin-induced increase in blood flow. Intracisternal administration of adrenomedullin induced dilation of the basilar and other major cerebral arteries in a dose-dependent manner, accompanied by an increase in the concentration of cyclic AMP in the cerebrospinal fluid. Adrenomedullin also induced relaxation of isolated basilar and middle cerebral arterial rings. These data suggest that adrenomedullin induces vasodilation of cerebral arteries and an increase in vertebral blood by acting at CGRP receptors positively coupled to adenylate cyclase, and that these effects are not dependent on nitric oxide or prostaglandin formation.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptídeos
/
Peptídeo Relacionado com Gene de Calcitonina
/
Circulação Cerebrovascular
/
Amiloide
Limite:
Animals
/
Female
/
Humans
/
Male
Idioma:
En
Revista:
J Cereb Blood Flow Metab
Ano de publicação:
1995
Tipo de documento:
Article
País de afiliação:
Japão