Modulation by estradiol of rabbit atrial chronotropic response to histamine.
The chronotropic response (delta rate) to histamine of atria from estradiol 17-beta (E2; 0.1 mg/kg)-treated (14 days) rabbit was significantly greater compared to those from control rabbits. However, the maximum response of atria from rabbits treated with a higher dose of E2 (1.0 mg/kg) was not significantly different from control. Cimetidine (2.8 X 10(-7) M) inhibited the theoretical maximum income in rate to histamine in all 3 groups, control 25%, E2 (0.1 mg) 42% and E2 (1.0 mg) 35%.
D000818:Animals; D016275:Atrial Function; D002927:Cimetidine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D006321:Heart / Q000187:drug effects / Q000502:physiology*; D006325:Heart Atria / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006632:Histamine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D066298:In Vitro Techniques; D011817:Rabbits; D013997:Time Factors
D004958:Estradiol; D002927:Cimetidine; D006632:Histamine; C027556:histamine phosphate