Schein Vanessa, Fernandes Chittó Ana Lúcia, Etges Rodrigo, Kucharski Luiz Carlos, van Wormhoudt Alain, Da Silva Roselis S M
Department of Physiology, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, 90050-170 Porto Alegre, RS, Brazil.
Comp Biochem Physiol B Biochem Mol Biol. 2005 Apr;140(4):561-7. doi: 10.1016/j.cbpc.2004.12.002. Epub 2005 Jan 15.
We investigated the transport of (14)C-methylaminoisobutyric acid ((14)C-MeAIB) and (14)C-alanine oxidation in hepatopancreas and jaw muscle of Chasmagnathus granulata submitted to 24, 72, and 144 h of hypo- or hyperosmotic stress. While (14)C-MeAIB uptake increased in jaw muscle and hepatopancreas from crabs submitted to hyperosmotic stress, it did not change in tissues from animals submitted to hypo-osmotic stress. Incubation of jaw muscle and hepatopancreas from control groups with 1 mM ouabain did not decrease (14)C-MeAIB uptake. However, ouabain prevented (14)C-MeAIB uptake in hepatopancreas at 24 h of hyperosmotic stress. In contrast, in jaw muscle from crabs submitted to the same conditions, (14)C-MeAIB uptake was not prevented by ouabain in the incubation medium. Jaw muscle from the control group produced four times more (14)CO(2) from (14)C-alanine than the hepatopancreas. During hypo-osmotic stress, amino acid oxidation does not seem to be one of the pathways implicated in the decrease of the amino acid pools in hepatopancreas and jaw muscle. In contrast, during hyperosmotic stress the reduction in (14)C-alanine oxidation appears to be one of the mechanisms involved in the increase of the amino acid pool in the hepatopancreas.
我们研究了经受24小时、72小时和144小时低渗或高渗应激的颗粒巨螯蟹肝胰腺和颌肌中（14）C-甲基氨基异丁酸（（14）C-MeAIB）的转运以及（14）C-丙氨酸氧化情况。在经受高渗应激的螃蟹的颌肌和肝胰腺中，（14）C-MeAIB摄取增加，而在经受低渗应激的动物组织中则没有变化。用1 mM哇巴因孵育对照组的颌肌和肝胰腺，并没有降低（14）C-MeAIB摄取。然而，哇巴因在高渗应激24小时时可阻止肝胰腺摄取（14）C-MeAIB。相反，在经受相同条件的螃蟹的颌肌中，孵育培养基中的哇巴因并未阻止（14）C-MeAIB摄取。对照组的颌肌由（14）C-丙氨酸产生的（14）CO2比肝胰腺多四倍。在低渗应激期间，氨基酸氧化似乎不是肝胰腺和颌肌中氨基酸池减少所涉及的途径之一。相反，在高渗应激期间，（14）C-丙氨酸氧化的减少似乎是肝胰腺中氨基酸池增加所涉及的机制之一。
