Changes in sensitivity of rat heart to norepinephrine and isoproterenol during pre- and postnatal development and its relation to sympathetic innervation.
Changes in sensitivity of rat heart to norepinephrine and isoproterenol during pre- and postnatal development and its relation to sympathetic innervation.
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大鼠心脏在出生前后发育过程中对去甲肾上腺素和异丙肾上腺素敏感性的变化及其与交感神经支配的关系。
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发表时间：
1988
期刊：
影响因子：
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通讯作者：
Y. Kasuya
中科院分区：
文献类型：
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作者：
K. Shigenobu;H. Tanaka;Y. Kasuya
交感神经支配和肾上腺素能受体激动剂的敏感性之间可能存在的相关性进行了检查与发育中的大鼠心脏。右心房对酪胺（TYR）的变时性反应直到妊娠第15天才出现。妊娠17天后，TYR的最大变时性与去甲肾上腺素（NE）的最大变时性相等，表明在此期间窦房结的功能性交感神经支配已经发育。在心室，TYR反应性在出生时较低，并随年龄增加，表明在出生后早期增加交感神经支配。在心房和心室中，对NE的敏感性在胎儿早期是高的，随后在交感神经支配开始后降低10倍。在对异丙肾上腺素的敏感性中观察到类似的变化，表明这种敏感性变化的后连接性质。从1天和1周龄的新生儿心室之间的二丁酰环磷酸腺苷和毛喉素的敏感性没有差异，这表明β受体腺苷酸环化酶系统的变化作为这种敏感性变化的原因。功能性交感神经支配和连接后敏感性变化之间的平行关系支持交感神经对心肌发育施加营养影响以调节对激动剂的敏感性的假设。
Possible correlation between sympathetic innervation and sensitivity to adrenergic agonists was examined with developing rat hearts. Chronotropic responses of right atria to tyramine (TYR) was absent until the 15th day of gestation. After the 17th day of gestation, the maximum chronotropism by TYR was equal to that by norepinephrine (NE), indicating the development of functional sympathetic innervation to sinus node during this period. In ventricle, TYR responsiveness was low at birth and increased with age, indicating an increased sympathetic innervation during early postnatal period. Both in atria and ventricle, sensitivity to NE was high in early fetal ages followed by a 10-fold decrease after the onset of sympathetic innervation. Similar changes were observed in the sensitivity to isoproterenol, suggesting the postjunctional nature of this sensitivity change. There was no difference in sensitivities to dibutyryl cyclic AMP and forskolin between ventricles from 1-day- and 1-week-old neonates, suggesting changes in beta-receptor-adenylate cyclase system as a cause of this sensitivity change. The observed parallelism between functional sympathetic innervation and postjunctional sensitivity changes supports the hypothesis that sympathetic nerve exerts trophic influence upon cardiac muscle development to regulate the sensitivity to agonists.