Sun L S, Ursell P C, Robinson R B
Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, New York 10032.
Am J Physiol. 1991 Sep;261(3 Pt 2):H969-73. doi: 10.1152/ajpheart.1991.261.3.H969.
The onset of sympathetic innervation induces a developmental change in the cardiac alpha 1-adrenergic chronotropic response from an increase to a decrease in rate. The mechanism by which innervation induces this alteration is unknown. Neuropeptide Y (NPY), which is found abundantly in cardiac sympathetic nerve terminals, was considered as a possible mediator for this effect. Chronic conditioning by NPY in noninnervated myocyte cultures stimulated the effect of sympathetic innervation in inducing the alpha 1-inhibitory chronotropic response. Chronic conditioning by the NPY antagonist PYX-2 blocked the effect of innervation. Thus endogenous NPY may modulate alpha 1-adrenergic responsiveness during the ontogeny of cardiac sympathetic innervation.
交感神经支配的开始会引起心脏α1 - 肾上腺素能变时反应的发育性变化，即心率从增加变为降低。神经支配诱导这种改变的机制尚不清楚。神经肽Y（NPY）在心脏交感神经末梢中大量存在，被认为可能是这种效应的介质。在未受神经支配的心肌细胞培养物中，用NPY进行慢性预处理可刺激交感神经支配诱导α1 - 抑制性变时反应的作用。用NPY拮抗剂PYX - 2进行慢性预处理可阻断神经支配的作用。因此，内源性NPY可能在心脏交感神经支配的个体发生过程中调节α1 - 肾上腺素能反应性。
