期刊
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY
卷 230, 期 -, 页码 28-38出版社
ELSEVIER SCIENCE INC
DOI: 10.1016/j.cbpa.2018.12.012
关键词
Channichthyidae; Adrenaline; Adenosine; Heart rate; Conductance
资金
- National Science Foundation [ANT 1341602, ANT 1341663]
- Swedish Research council (Vetenskapsradet) [2015-05286]
- Canadian NSERC
- Canada Research Chair
- Swedish Research Council [2015-05286] Funding Source: Swedish Research Council
Icefishes characteristically lack the oxygen-binding protein haemoglobin and therefore are especially reliant on cardiovascular regulation to augment oxygen transport when oxygen demand increases, such as during activity and warming. Using both in vivo and in vitro experiments, we evaluated the roles for adrenaline and adenosine, two well-established cardio- and vasoactive molecules, in regulating the cardiovascular system of the blackfin icefish, Chaenocephalus aceratus. Despite increasing cardiac contractility (increasing twitch force and contraction kinetics in isometric myocardial strip preparations) and accelerating heart rate (f(H)), adrenaline (5 nmol kg(-1) bolus infra-arterial injection) did not significantly increase cardiac output ((Q) over dot) in vivo because it elicited a large decrease in vascular conductance (G(sys)). In contrast, and despite preliminary data suggesting a direct negative inotropic effect of adenosine on isolated atria and little effect on isolated ventricle strips, adenosine (500 nmol kg-1) generated a large increase in (Q) over dot by increasing G(sys), a change reminiscent of that previously reported during both acute warming and invoked activity. Our data thus illustrate how (Q) over dot in C. aceratus may be much more dependent on peripheral control of vasomotor tone than direct regulation of the heart.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据