The importance of EDHF in endothelium-dependent relaxation increases distally in mesenteric arteries depending upon the contracting agent.

Autor:	Hurjui L; Department of Physiology, 'Gr. T. Popa' University of Medicine and Pharmacy, Iaşi, Romania., Serban IL, Oprişa C, Tucaliuc ES, Hogaş MM, Tucaliuc D, Hurjui I, Luca V, Serban DN
Jazyk:	angličtina
Zdroj:	Revista medico-chirurgicala a Societatii de Medici si Naturalisti din Iasi [Rev Med Chir Soc Med Nat Iasi] 2011 Jan-Mar; Vol. 115 (1), pp. 168-70.
Abstrakt:	Aim: The importance of endothelium-derived hyperpolarizing factor (EDHF) in endothelium-dependent relaxation (EDR) is influenced by multiple factors, including vascular territory and caliber, pre-existing tone and its determining factors. Method: Using isometric myography we noticed that in rat mesenteric resistance arteries (RMA2; 2nd order branches) EDHF-mediated relaxation is increased when precontraction is induced by prostaglandin F2 (PGF) compared to phenylephrine (PHE) and we investigated the participation of certain K channels. Here we extend the study on more proximal vascular fragments; from mesenteric arcade and from 1st order branches. Results: The EDHF component of EDR is stronger distally only when precontraction is induced by PHE. Moreover, morphometric analysis shows a strong inverse correlation between the magnitude of EDHF response and arterial caliber. Conclusions: Other authors have shown that EDHF increases in relative importance distally, but we show that this change in EDR profile depends upon the contracting agent used, with implications regarding the physiological relevance of accumulated data refering to EDHF and nitric oxide as mediators of EDR in resistance arteries.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu