ATP-induced, P2U purinoceptor-mediated constriction of isolated, perfused mesenteric beds of the rat.
alpha,beta-Methylene ATP (alpha, beta-mATP), ATP and UTP dose dependently increased the perfusion pressure of rat mesenteric arteries with a potency order of alpha, beta-mATP >> ATP > UTP. In the veins, while alpha, beta-mATP did not affect the pressure, both ATP and UTP equi-potently increased it. The arterial ATP response was attenuated to some degree by suramin (100 microM), but markedly and to a similar extent by pyridoxal-phosphate-6-azophenyl-2',4-disulphonic acid (PPADS 30 microM) and alpha, beta-mATP (100 nmol). The venous response was not affected by PPADS or alpha, beta-mATP, but was slightly attenuated by suramin. Thus, ATP seems to elicit arterial constriction predominantly by stimulating P2X, but venous constriction by stimulating P2U purinoceptors.
Ohara
N
N
Department of Pharmacology, Hatano Research Institute, Food and Drug Safety Center Ochiai, Kanagawa, Japan. n-ohara@qb3.so-net.ne.jp
Konishi
C
C
Naito
Y
Y
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology* / Q000502:physiology; D000818:Animals; D004347:Drug Interactions; D066298:In Vitro Techniques; D008297:Male; D008642:Mesenteric Veins / Q000187:drug effects* / Q000502:physiology; D010477:Perfusion; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D018048:Receptors, Purinergic P2 / Q000187:drug effects / Q000502:physiology*; D058473:Receptors, Purinergic P2Y2; D013498:Suramin / Q000494:pharmacology; D014544:Uridine Triphosphate / Q000494:pharmacology / Q000502:physiology; D014661:Vasoconstriction / Q000187:drug effects*
C546387:P2ry2 protein, rat; D018048:Receptors, Purinergic P2; D058473:Receptors, Purinergic P2Y2; D013498:Suramin; D000255:Adenosine Triphosphate; C002630:alpha,beta-methyleneadenosine 5'-triphosphate; D014544:Uridine Triphosphate