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pH降低和尼古丁对家兔颈动脉体化学感受器活动的影响

庄甲举, 庞雷, 董力

河北省医学科学院生理研究室. 河北, 石家庄 050021；解放军石家庄医学高等专科学校科研中心. 河北, 石家庄 050081

摘要

在29只家兔的颈动脉体-窦神经标本，记录了55个窦神经中化学感受性传入单位的电活动。结果如下：(1)灌流液pH降低时，所有单位的放电均增加，频率由0.86±0.21增至1.75±0.40imp/s(P＜0.001)。(2)在灌洗液中加入尼古丁(1，3，6，10和15μg/ml)后，10个单位的自发放电频率，由0.60±0.21分别增加到0.96±0.21，1.19±0.30，1.24±0.29，1.48±0.41和1.82±0.39imp/s，呈明显的剂量依赖性肝(r=0.94，P＜0.001)。简箭毒可阻断尼古丁的作用，但对自发放电无显著影响。(3)当以酸性Locke氏溶液灌流标本时，19个单位的放电频率由0.95±0.34增至1.84±0.55imp/s；在酸性灌流液中加入尼古丁后，放电频率由0.96±0.25增至1.53±0.24imp/s；与单纯酸刺激时相比，放电频率增加幅度减小(P＜0.05)。(4)17个自发放电频率为1.08±0.33imp/s的单位，换以酸性Locke氏液灌流后，放电频率增加到1.64±0.43imp/s；加筒箭毒后，由对照的1.01±0.34增至1.70±0.43imp/s；灌流液pH降低时筒箭毒对化学感受性单位放电频率的变化无显著影响。上述结果提示：(1)ACh在颈动脉体化学感受性功能方面可能仅起调质的作用。(2)pH降低时颈动脉体化学感受性功能活动增强与N-型胆碱能受体无关。

关键词： 乙酰胆碱; 颈动脉体化学感受器; 传入单位放电; N-受体; pH降低

Effects of low pH and nicotine on carotid body chemoreceptor activity in the rabbit

Zhuang Jiaju, Pang Lei, Dong Li

Department of Pathophysiology, Hebei Academy of Medical Science. Shijiazhuang 050021, Hebei, China

Abstract

The unit discharges of carotid chemosensory afferent fihers were rec0rded in the in vitro carotid body (CB) -sinus nerve preparations (n=55) from 29 ralibits. The results were as follows: (1) The discharge of all the units increased from 0.86+-0.21 to 1.75+-0.40 imp/s (P<0.001) upon lowering the pH of modified Locke solution. (2)Addition of nicotine at doses of 1, 3, 6, 10 and 15 #mu#g/ml to the solution led to a dosedependent increase in the discharge from 0.60+-0.21 to 0.96+-0.21, 1.19+-0.30,1.24+-0.29, 1.48+-0.41 and 1.82+-0.39 imp/s, respectively (r=0.94, P<0.001) n=10). Nicotinic stimulati0n was antagonized by D-tub0curarine but the basal discharge was not significantly affected. (3) Superfusion of the CB with acid solution increased the discharge from 0.95+-0.34 to 1.84+-0.55 imp/s (P<0.01, n=19);Afer injections of nicotine 1～5 #mu#g/ml to acid perfusate the unit discharge showed an increase from 0.96+-0.25 to 1.53+-0.24 imp/s.

Key words: Acetylecholine;Carotid body chemoreceptor;Afferent unit discharee;N-receptor;Low pH

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引用本文：

庄甲举, 庞雷, 董力. pH降低和尼古丁对家兔颈动脉体化学感受器活动的影响[J]. 生理学报 1997; 49 (5): .

Zhuang Jiaju, Pang Lei, Dong Li. Effects of low pH and nicotine on carotid body chemoreceptor activity in the rabbit. Acta Physiol Sin 1997; 49 (5): (in Chinese with English abstract).