Desensitization to histamine in the absence of external Ca++ in the guinea-pig taenia caecum.
Short-term desensitization of the contractile response of the guinea-pig taenia caecum to histamine was tested in the absence of Ca++. Desensitization was monitored both by the fall of histamine response and by the decrease of irreversible blockade by phenoxybenzamine. In Ca++-free solution with 0.2 mM EGTA, desensitization occurred as in normal physiological solution containing Ca++.
D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D002432:Cecum / Q000187:drug effects / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004533:Egtazic Acid / Q000494:pharmacology; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology; D010643:Phenoxybenzamine / Q000494:pharmacology
D010643:Phenoxybenzamine; D004533:Egtazic Acid; D006632:Histamine; D002118:Calcium