在山羊适应低氧环境后，颈动脉体多巴胺能机制发挥作用。

Carotid body dopaminergic mechanisms are functional after acclimatization to hypoxia in goats.

作者信息

Janssen P L, O'Halloran K D, Pizarro J, Dwinell M R, Bisgard G E

机构信息

Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison 53706, USA.

出版信息

Respir Physiol. 1998 Jan;111(1):25-32. doi: 10.1016/s0034-5687(97)00060-1.

DOI:10.1016/s0034-5687(97)00060-1

PMID:9496469

Abstract

Ventilatory acclimatization to sustained hypoxia (VASH) is the time-dependent increase in ventilation that occurs during prolonged exposure to hypoxia. We tested the hypothesis that carotid body (CB) dopaminergic mechanisms are down-regulated during VASH, which would allow CB afferent discharge and ventilation to increase beyond the initial response to hypoxia. Domperidone (DOM; 1.0 mg.kg-1) was administered intravenously to block CB dopamine (DA) receptors after VASH was complete in awake goats. DOM caused a significant augmentation of the ventilatory response to hypoxia in acclimatized goats, failing to support the hypothesis. We conclude that inhibitory CB dopaminergic function is not significantly reduced following prolonged hypoxia, and that down-regulation of CB dopaminergic mechanisms may not be involved in VASH in the goat.

摘要

对持续性低氧的通气适应（VASH）是指在长时间暴露于低氧环境期间通气量随时间的增加。我们检验了这样一个假说，即在VASH过程中颈动脉体（CB）的多巴胺能机制被下调，这将使CB传入放电和通气量增加超过对低氧的初始反应。在清醒山羊完成VASH后，静脉注射多潘立酮（DOM；1.0mg·kg-1）以阻断CB多巴胺（DA）受体。DOM使适应低氧的山羊对低氧的通气反应显著增强，这一结果不支持该假说。我们得出结论，长时间低氧后CB多巴胺能抑制功能并未显著降低，并且CB多巴胺能机制的下调可能不参与山羊的VASH。