The inhibitory action of suramin on the P2-purinoceptor response in smooth muscle cells of guinea-pig taenia caeci.
The effect of suramin on the smooth muscle cell response of guinea-pig taenia caeci to P2-purinoceptor and alpha 1-adrenoceptor stimulation was measured. The ATP-induced relaxation in potassium (20 mM) pre-contracted taenia caeci was inhibited by suramin (3 x 10(-4) M). The P2-purinoceptor-induced hyperpolarization elicited by ATP both in the presence and absence of calcium was also reduced by suramin. The alpha 1-adrenoceptor-mediated relaxation evoked by phenylephrine was only affected by suramin at low concentrations of the agonist. The results indicate that suramin inhibits the ATP response by interacting with P2y-purinoceptors.
den Hertog
A
A
Department of Pharmacology/Clinical Pharmacology, University of Groningen, The Netherlands.
Nelemans
A
A
Van den Akker
J
J
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D002432:Cecum / Q000187:drug effects; D004594:Electrophysiology; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D010656:Phenylephrine / Q000494:pharmacology; D011224:Prazosin / Q000494:pharmacology; D011983:Receptors, Purinergic / Q000187:drug effects*; D013498:Suramin / Q000494:pharmacology*; D013779:Tetrodotoxin / Q000494:pharmacology
D011983:Receptors, Purinergic; D010656:Phenylephrine; D013779:Tetrodotoxin; D013498:Suramin; D000255:Adenosine Triphosphate; D011224:Prazosin