Woods W T, Urthaler F, James T N
Am J Physiol. 1978 Apr;234(4):H412-5. doi: 10.1152/ajpheart.1978.234.4.H412.
Postnatal development of autonomic control of heart rate was evaluated in the sinus nodes of isolated, perfused right atria obtained from 21 sibling puppies in three different litters between 3 and 11 wk postpartum. Age-related changes in response to autonomic blockade indicated that propranolol administered after atropine had its most profound direct depressive effect on less mature atrial cells. In the youngest sinus nodes the familial antimuscarinic action (increase in sinus rate) of atropine was regularly preceded by a brief period of cholinomimetic action (a marked slowing of sinus rate) in the youngest sinus nodes. These two opposing effects of atropine underwent a developmental change during the 2-mo study. The cholinomimetic action diminished, whereas the antimuscarinic action increased as a function of age.
对产后3至11周的三只不同窝的21只同胞幼犬的离体灌注右心房窦房结进行心率自主控制的产后发育评估。自主神经阻滞反应的年龄相关变化表明，阿托品给药后给予普萘洛尔对较不成熟的心房细胞具有最显著的直接抑制作用。在最年幼的窦房结中，阿托品的家族性抗胆碱作用（窦性心率增加）之前通常会有一段短暂的拟胆碱作用（窦性心率明显减慢）。在为期2个月的研究中，阿托品的这两种相反作用发生了发育变化。拟胆碱作用减弱，而抗胆碱作用随年龄增长而增强。
