Eliason Erika J, Higgs David A, Farrell Anthony P
Department of Zoology, University of British Columbia, Vancouver, BC, Canada.
Comp Biochem Physiol A Mol Integr Physiol. 2008 Apr;149(4):380-8. doi: 10.1016/j.cbpa.2008.01.033. Epub 2008 Feb 5.
The present study is the first to simultaneously and continuously measure oxygen consumption (MO(2)) and gastrointestinal blood flow (q(gi)) in fish. In addition, while it is the first to compare the effects of three isoenergetic diets on q(gi) in fish, no significant differences among diets were found for postprandial MO(2), q(gi) or heart rate (f(H)) in rainbow trout, Oncorhynchus mykiss. Postprandial q(gi), f(H) and MO(2) were significantly elevated above baseline levels by 4 h. Postprandial q(gi) peaked at 136% above baseline after 11 h, f(H) peaked at 110% above baseline after 14 h and MO(2) peaked at 96% above baseline after 27 h. Moreover, postprandial MO(2) remained significantly elevated above baseline longer than q(gi) (for 41 h and 30 h, respectively), perhaps because most of the increase in MO(2) associated with feeding is due to protein handling, a process that continues following the absorption of nutrients which is thought to be the primary reason for the elevation of q(gi). In addition to the positive relationships found between postprandial MO(2) and q(gi) and between postprandial MO(2) and f(H), we discovered a novel relationship between postprandial q(gi) and f(H).
本研究首次同时连续测量鱼类的耗氧量（MO₂）和胃肠道血流量（qgi）。此外，本研究首次比较了三种等能量日粮对鱼类qgi的影响，但在虹鳟（Oncorhynchus mykiss）中，日粮之间在餐后MO₂、qgi或心率（fH）方面未发现显著差异。餐后4小时，qgi、fH和MO₂显著高于基线水平。餐后qgi在11小时后达到比基线高136%的峰值，fH在14小时后达到比基线高110%的峰值，MO₂在27小时后达到比基线高96%的峰值。此外，餐后MO₂高于基线水平的时间比qgi长得多（分别为41小时和30小时），这可能是因为与摄食相关的MO₂增加大部分是由于蛋白质处理，这一过程在营养物质吸收后仍在继续，而营养物质吸收被认为是qgi升高的主要原因。除了发现餐后MO₂与qgi之间以及餐后MO₂与fH之间存在正相关关系外，我们还发现了餐后qgi与fH之间的一种新关系。
