Laher I, McNeill J H
Can J Physiol Pharmacol. 1980 Sep;58(9):1114-6. doi: 10.1139/y80-166.
The effects of histamine were studied in atria obtained from untreated and reserpine-pretreated rats. At high doses, histamine caused a positive chronotropic response that was not antagonized by either promethazine or cimetidine. In the presence of propranolol or in atria from reserpine-pretreated rats histamine caused an atropine-sensitive negative chronotropic response. Large doses of histamine also caused a positive inotropic response in left atria that were antagonized by the beta adrenoceptor antagonist propranolol. Reserpine pretreatment abolished the inotropic response of histamine in the rat heart. The results indicate that in large doses histamine causes an indirect stimulation of beta adrenoceptors (right and left atrium) by releasing endogenous noradrenaline and of muscarinic receptors (right atrium) by releasing acetylcholine.
在从未经处理和经利血平预处理的大鼠获取的心房中研究了组胺的作用。高剂量时，组胺引起正性变时反应，该反应不受异丙嗪或西咪替丁的拮抗。在普萘洛尔存在的情况下，或在来自经利血平预处理大鼠的心房中，组胺引起对阿托品敏感的负性变时反应。大剂量组胺还在左心房引起正性变力反应，该反应被β肾上腺素能受体拮抗剂普萘洛尔所拮抗。利血平预处理消除了组胺在大鼠心脏中的变力反应。结果表明，大剂量组胺通过释放内源性去甲肾上腺素间接刺激β肾上腺素能受体（右心房和左心房），并通过释放乙酰胆碱间接刺激毒蕈碱受体（右心房）。
