Zenteno-Savin T, Castellini M A
Institute of Marine Science, University of Alaska Fairbanks, USA.
Comp Biochem Physiol C Pharmacol Toxicol Endocrinol. 1998 Jan;119(1):7-12. doi: 10.1016/s0742-8413(97)00137-0.
Prolonged and repetitive breath-hold periods (apnea) during and sleep are a routine component in the ecological physiology of marine mammals. Seals are among the few mammals in which control of heart rate (HR) can be studied independent of respiration, without pharmacochemical manipulation. We hypothesized that the vasoactive hormones angiotensin II (Ang II), arginine vasopressin (AVP), and atrial natriuretic peptide (ANP) were involved in the control of cardiovascular function in seals, and that the relationship was dependent upon input from the respiratory system. Venous plasma samples were collected and electrocardiograms were recorded from Northern elephant seal (Mirounga angustirostris) and Weddell seal (Leptonychotes weddellii) pups during both spontaneous breathing (eupnea) and apnea. Instantaneous HR and simultaneous plasma levels of ANP, AVP, and Ang II from periods of eupnea and apnea were compared. In these seal pups, apnea was associated with bradycardia, increased ANP, and decreased AVP and Ang II. The results support the hypothesis of a complex involvement between the vasoactive hormones and the control of cardiovascular function, and provide evidence for differential levels of control during periods of eupnea and apnea.
在睡眠期间以及睡眠过程中，长时间重复性屏气（呼吸暂停）是海洋哺乳动物生态生理学的常规组成部分。海豹是少数几种能够在不进行药物化学操作的情况下，独立于呼吸来研究心率（HR）控制的哺乳动物之一。我们假设血管活性激素血管紧张素II（Ang II）、精氨酸加压素（AVP）和心房利钠肽（ANP）参与了海豹心血管功能的控制，并且这种关系取决于呼吸系统的输入。在自发呼吸（平稳呼吸）和呼吸暂停期间，从北海象海豹（Mirounga angustirostris）和威德尔海豹（Leptonychotes weddellii）幼崽身上采集静脉血浆样本并记录心电图。比较了平稳呼吸期和呼吸暂停期的瞬时心率以及同时期血浆中ANP、AVP和Ang II的水平。在这些海豹幼崽中，呼吸暂停与心动过缓、ANP升高以及AVP和Ang II降低有关。这些结果支持了血管活性激素与心血管功能控制之间存在复杂关联的假设，并为平稳呼吸期和呼吸暂停期不同水平的控制提供了证据。
