Transfer of lipids between hemolymph and hepatopancreas in the shrimp Macrobrachium borellii.
Crustacean lipids are transported in the hemolymph by an HDL. The hepatopancreas is the most important and active organ regarding lipid metabolism, so we studied the interchange of FA and acylglycerols between both components of the hepatopancreas-hemolymph system in the decapod crustacean Macrobrachium borellii. The hepatopancreas and a sole plasma lipoprotein were labeled by in vivo incubations with 14C palmitic acid injected into the hemolymph. Then they were incubated in vitro with unlabeled hepatopancreas and hemolymph, and the transfer of lipids between them was measured by radiochromatographic techniques. It was determined in vivo that more than 80% of the circulating palmitic acid was taken up by the hepatopancreas and incorporated into PC and TAG. Both classes of lipids, but mainly PC, were transferred back from tissues to the hemolymph. Lipid transfer was also demonstrated in vitro. The transfer of PC (30% of labeling) as well as that of FFA (48% of labeling) from hemolymph to hepatopancreas was determined. On the other hand, FFA were released more efficiently than the acylglycerols from intact hepatopancreas to hemolymph, and they were the only lipid transferred when the hepatopancreas had been previously washed.
Instituto de Investigaciones Bioquímicas de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad Nacional de La Plata, Argentina.
Fernando
F
García
María
M
González-Baró
Ricardo
R
Pollero
D000818:Animals; D001692:Biological Transport; D003445:Crustacea; D004064:Digestive System / Q000378:metabolism*; D005230:Fatty Acids, Nonesterified / Q000097:blood / Q000378:metabolism*; D005260:Female; D006458:Hemolymph / Q000378:metabolism*; D050356:Lipid Metabolism; D008055:Lipids / Q000097:blood; D008297:Male; D008567:Membranes, Artificial
D005230:Fatty Acids, Nonesterified; D008055:Lipids; D008567:Membranes, Artificial