X. Casanovas et al., EFFECTS OF TEMPERATURE ON IN-VITRO PALMITIC ACID UPTAKE BY CHICKEN AND RAT INTESTINAL TISSUE, ARCH I PHYS, 102(3), 1994, pp. 233-235
Citations number
12
Categorie Soggetti
Physiology,Biology,Biophysics
Journal title
Archives internationales de physiologie, de biochimie et de biophysique
The intestinal absorption of fatty acids proceeds by simple or facilit
ated diffusion, a mechanism which is affected by temperature. However,
most studies in this field have not taken into consideration the fact
that birds have higher physiological temperature than mammals, the ab
sorption being studied at 37-degrees-C in both cases. The aim of this
work has been to find out whether the higher palmitic acid (PA) uptake
rate in birds (chickens) compared to mammals (rats) is attributable t
o the differences between their body temperatures (41.5-degrees-C for
chickens and 37.5-degrees-C for rats). PA-uptake was studied in intest
inal (ileal and jejunal) tissue samples of both Hybro broiler chickens
(male and female, 4 weeks-old) and Ico:OFA rats (males and females, 8
weeks-old). The intestinal tissue samples were incubated in micellar
solution (0.6 mM C-14-PA; 0.3 mM monoolein; 3.4 mM sodium taurodeoxych
olate) at 37.5-degrees-C and 41.5-degrees-C in both cases. Chicken int
estinal tissue incorporated PA with higher efficiency at 41.5-degrees-
C than at 37.5-degrees-C. In contrast, increasing the incubation tempe
rature to 41.5-degrees-C led to a decrease in PA uptake by female rat
intestinal tissue whereas specimens from male rats exhibited the same
absorptive efficiency. These results suggest that the incubation tempe
rature determines to some extent the efficiency of fatty acid uptake.
However the fact that the temperature caused opposite effects in rats
and chickens indicates that the changes in temperature affect the intr
acellular processing of the fatty acids already taken up rather than t
he diffusion of fatty acids through the enterocyte brush-border membra
ne.