Tomomatsu E, Nishi K
Am J Physiol. 1982 Oct;243(4):H546-50. doi: 10.1152/ajpheart.1982.243.4.H546.
The impulse activity in single baroreceptor fibers of the carotid sinus nerve to the carotid sinus was studied in newborn rabbits (9--11 days old) during nonpulsatile perfusion of in vitro carotid sinus preparations. Results were compared with those obtained from adult rabbits. Seventy-eight baroreceptor fibers from 10 newborn rabbits showed lower threshold pressure (54.6 +/- 2.5 mmHg) than that of 59 fibers from adult rabbits (74.2 +/- 4.1). The gain of 14 baroreceptors from newborn rabbits (0.62 +/- 0.07 impulses . s-1 . mmHg-1) was higher than that of 21 baroreceptors from adult rabbits (0.38 +/- 0.03). Results provided direct evidence that carotid sinus baroreceptors in the newborn animals were more sensitive to pressure changes than those in the adult. It is suggested that depressed baroreceptor reflex activity previously observed in most newborn animals is not due to underdeveloped afferent activity of the baroreceptors but to other mechanisms including the efferent control systems.
在新生兔（9 - 11日龄）体外颈动脉窦制备物的非搏动性灌注过程中，研究了颈动脉窦神经单根压力感受器纤维向颈动脉窦的冲动活动。将结果与成年兔的结果进行比较。来自10只新生兔的78根压力感受器纤维的阈值压力（54.6±2.5 mmHg）低于来自成年兔的59根纤维（74.2±4.1）。来自新生兔的14根压力感受器的增益（0.62±0.07脉冲·s⁻¹·mmHg⁻¹）高于来自成年兔的21根压力感受器（0.38±0.03）。结果提供了直接证据，表明新生动物的颈动脉窦压力感受器对压力变化比成年动物更敏感。有人提出，先前在大多数新生动物中观察到的压力感受器反射活动降低不是由于压力感受器传入活动发育不全，而是由于包括传出控制系统在内的其他机制。
