C. Wallaert et Pj. Babin, EFFECTS OF TEMPERATURE-VARIATIONS ON DIETARY-LIPID ABSORPTION AND PLASMA-LIPOPROTEIN CONCENTRATIONS IN TROUT (ONCORHYNCHUS-MYKISS), Comparative biochemistry and physiology. B. Comparative biochemistry, 109(2-3), 1994, pp. 473-487
In juvenile rainbow trout (Oncorhynchus mykiss) the peak of dietary li
pid absorption occurred later at low compared with high temperature. R
apid temperature variations modified plasma concentrations of glucose,
lipids and lipoproteins, with no effect on free glycerol. The concent
ration of these parameters was not affected during the progressive sea
sonal temperature changes. The plasma concentration of very low densit
y lipoproteins (VLDL) increased by two- to three-fold within two days
after the onset of cold acclimation (CA) or warm acclimation, independ
ently of alterations in dietary lipid absorption. The high concentrati
on of VLDL induced an increase in low density lipoproteins (LDL) conce
ntration after several days. CA induced a rapid and transitory decreas
e in the concentration of high density lipoproteins (HDL) of about 20%
. Incomplete successive acclimations resulted in a cumulative effect o
n the increase of VLDL (10-fold) and of LDL (three-fold). In cold-accl
imated trout, the persistent hypertriglyceridemia and high plasma conc
entration of VLDL observed for several weeks after fasting suggest a l
ong-term increase in the secretion of hepatic VLDL. The results indica
ted that plasma lipoprotein concentrations appear to be sensitive to t
he thermal adaptation process in trout exposed to rapid temperature va
riations.