Hepatopancreas gluconeogenesis during hyposmotic stress in crabs Chasmagnathus granulata maintained on high-protein or carbohydrate-rich diets.
The incorporation of [14C]-alanine or [14C]-lactate into glucose was measured in hepatopancreas fractions from Chasmagnathus granulata crabs adapted to a high protein or a carbohydrate-rich diet and submitted or not (control group) to hyposmotic stress. Gluconeogenic capacity and phosphoenolpyruvate carboxykinase (PEPCK) activity increased during acclimation to a dilute medium in C. granulata hepatopancreas. In intact animals, high hemolymph urea levels occurred for the high-protein regimen and for crabs fed both diets and submitted to hyposmotic stress. It could be that the amino acids released during hyposmotic stress are deaminated in the hepatopancreas, and that the carbon chains are used as substrate for gluconeogenesis. Hepatopancreas gluconeogenesis seems to be one of the pathways implicated in the metabolic adjustment of the amino acid pool during hyposmotic stress in C. granulata.
Oliveira
G T
GT
Department of Physiology, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, ICBS, Porto Alegre, Brazil.
da Silva
R S
RS
D000409:Alanine / Q000378:metabolism; D000818:Animals; D003386:Brachyura / Q000378:metabolism*; D004040:Dietary Carbohydrates / Q000378:metabolism*; D004044:Dietary Proteins / Q000378:metabolism*; D004064:Digestive System / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D019344:Lactic Acid / Q000378:metabolism; D008297:Male; D009997:Osmotic Pressure; D019764:Phosphoenolpyruvate Carboxykinase (ATP) / Q000378:metabolism
D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D019344:Lactic Acid; D007770:L-Lactate Dehydrogenase; D019764:Phosphoenolpyruvate Carboxykinase (ATP); D005947:Glucose; D000409:Alanine