The vascular effects of endothelin-1 (ET-1) and the release of prostacyclin and nitric oxide (NO) evoked by this peptide were analyzed in anesthetized, mechanically ventilated pigs. ET-1 induced biphasic responses in both the pulmonary and systemic vascular beds characterized by a transient hypotension followed by a long-lasting hypertension. To evaluate the involvement of prostacyclin and NO in the ET-1-dependent vascular response, we used indomethacin to block cyclooxygenase and NG-nitro-L-arginine methyl ester (L-NAME) to block NO synthase. The results show that the systemic hypotensive response to ET-1 is mediated by the release of prostanoids and NO, but these are not responsible for the pulmonary hypotension. Indomethacin reduced the hypertensive effect of ET-1, showing that this peptide can also activate release of vasoconstrictor cyclooxygenase metabolites. When L-NAME was administered after indomethacin, the pulmonary vasoconstrictor activity of ET-1 was counterbalanced by NO. By contrast, in pigs pretreated with indomethacin plus L-NAME ET-1 caused transient systemic vasoconstriction, followed by progressive reduction of vascular tone, probably because of release of vasodilator agents other than prostanoids or NO.
Differential release of prostacyclin and nitric oxide evoked from pulmonary and systemic vascular beds of the pig by endothelin-1 / M.G. Clement, M. Albertini. - In: PROSTAGLANDINS LEUKOTRIENES AND ESSENTIAL FATTY ACIDS. - ISSN 0952-3278. - 55:4(1996), pp. 279-285.
|Titolo:||Differential release of prostacyclin and nitric oxide evoked from pulmonary and systemic vascular beds of the pig by endothelin-1|
CLEMENT, MARIA GIOVANNA (Primo)
ALBERTINI, MARIANGELA (Ultimo)
|Settore Scientifico Disciplinare:||Settore VET/02 - Fisiologia Veterinaria|
|Data di pubblicazione:||1996|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1016/S0952-3278(96)90009-5|
|Appare nelle tipologie:||01 - Articolo su periodico|