Syvälahti E K, Ylitalo A
Life Sci. 1986 Sep 1;39(9):843-50. doi: 10.1016/0024-3205(86)90464-9.
Neuroendocrine and cardiac responses were studied in healthy volunteers with the classical muscarinic antagonist, atropine and the new antimuscarinic agent, pirenzepine. The secretion of prolactin (PRL) and growth hormone (GH) was increased after metoclopramide. Typically, an antidopaminergic drug such as metoclopramide decreases rather than increases GH concentrations in serum. Pretreatment with both atropine and pirenzepine abolished the increase of GH secretion, which suggests an important role of cholinergic mechanisms in the regulation of GH secretion. The increase of PRL secretion was not inhibited by the two muscarinic antagonists. With the doses used, antimuscarinic activities in serum were comparable after atropine and pirenzepine treatments for the most part of the study. Heart rate was, however, significantly increased during atropine and higher than during saline or pirenzepine treatments throughout the study period. When compared to placebo, pirenzepine lowered heart rate slightly but significantly. The exact mechanism of this effect is unclear. We conclude that in contrast to the identical neuroendocrine effects, the cardiac responses clearly differ during atropine and pirenzepine treatments which confirms the ability of pirenzepine to distinguish muscarinic receptor sites in the central nervous system from those of the heart.
在健康志愿者中，使用经典的毒蕈碱拮抗剂阿托品和新型抗毒蕈碱药物哌仑西平，研究神经内分泌和心脏反应。甲氧氯普胺后催乳素（PRL）和生长激素（GH）的分泌增加。通常，像甲氧氯普胺这样的抗多巴胺能药物会降低而非增加血清中GH的浓度。阿托品和哌仑西平预处理均消除了GH分泌的增加，这表明胆碱能机制在GH分泌调节中起重要作用。两种毒蕈碱拮抗剂均未抑制PRL分泌的增加。在所使用的剂量下，在研究的大部分时间里，阿托品和哌仑西平治疗后血清中的抗毒蕈碱活性相当。然而，在整个研究期间，阿托品治疗期间心率显著增加且高于生理盐水或哌仑西平治疗期间。与安慰剂相比，哌仑西平使心率略有但显著降低。这种效应的确切机制尚不清楚。我们得出结论，与相同的神经内分泌效应相反，阿托品和哌仑西平治疗期间心脏反应明显不同，这证实了哌仑西平能够区分中枢神经系统中的毒蕈碱受体位点与心脏中的受体位点。
