McQueen D S, Ribeiro J A
Q J Exp Physiol. 1981 Jul;66(3):273-84. doi: 10.1113/expphysiol.1981.sp002556.
The effects of beta-endorphin, vasoactive intestinal polypeptide (VIP) and cholecystokinin octapeptide (CCK-8) on carotid chemoreceptor activity have been investigated in cats anaesthetized with pentobarbitone. Spontaneous chemoreceptor discharge was decreased by intracarotid injection of beta-endorphin and by low doses of VIP, whereas it was increased by CCK-8 and higher doses of VIP, these effects being relatively long-lasting and often associated with changes in systemic blood pressure. The chemoexcitation evoked by acetylcholine and sodium cyanide was reduced during intracarotid infusion of any of the three peptides studied, and that caused by CO2-saturated Locke solution was reduced by beta-endorphin, largely unaltered by VIP and variably affected by CCK-8. The inhibitory effect of beta-endorphin was greatly reduced by naloxone, implying that it probably involved actions at naloxone-sensitive opiate receptors in the carotid body. Substance P was unable to overcome the chemoinhibitory effect of methionine enkephalin. Possible functions of polypeptides in the carotid body are discussed.
在戊巴比妥麻醉的猫身上，研究了β-内啡肽、血管活性肠肽（VIP）和八肽胆囊收缩素（CCK-8）对颈动脉化学感受器活动的影响。颈内注射β-内啡肽和低剂量的VIP可使化学感受器的自发放电减少，而CCK-8和高剂量的VIP则使其增加，这些效应持续时间相对较长，且常伴有全身血压的变化。在颈内输注所研究的三种肽中的任何一种时，乙酰胆碱和氰化钠引起的化学兴奋均降低，而β-内啡肽可降低由二氧化碳饱和的洛克溶液引起的化学兴奋，VIP对此基本无影响，CCK-8则有不同程度的影响。纳洛酮可大大降低β-内啡肽的抑制作用，这表明其可能作用于颈动脉体中对纳洛酮敏感的阿片受体。P物质无法克服甲硫氨酸脑啡肽的化学抑制作用。文中讨论了多肽在颈动脉体中的可能功能。
