Asunto(s)
Insulina/fisiología , Lípidos de la Membrana/fisiología , Animales , Transporte Biológico/efectos de los fármacos , Transporte Biológico/fisiología , Radioisótopos de Carbono , Diabetes Mellitus Experimental/metabolismo , Gangliósidos/metabolismo , Glucosa/metabolismo , Glucolípidos/metabolismo , Insulina/farmacología , Masculino , Oxidación-Reducción/efectos de los fármacos , Conejos , Ratas , Distribución Tisular/efectos de los fármacos , Distribución Tisular/fisiología , TritioRESUMEN
The contents of individual gangliosides in various tissues (e. g. heart, skeletal muscles, liver, brain, kidney, spleen, pancreas) under normal conditions and in alloxan diabetes as well as the incorporation of 1-14C-stearate into the phospholipid, glyceride and total ganglioside fractions were studied. The oxidation of 14C-fatty acid and the activities of neuraminidase and lipase in these tissues were determined. It was found that diabetes is concomitant with a marked decrease of the content and exchange of gangliosides, which is paralleled with activation of neuraminidase. The incorporation of 14C-stearate in the sphingomyelin and phosphatidylcholine fractions is significantly decreased, while that in the cardiolipin fraction is increased 1.5 - 2-fold. The oxidation of 14C-stearate is also increased, the degree of this increase being tissue-specific.
Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Gangliósidos/metabolismo , Glucolípidos/metabolismo , Fosfolípidos/metabolismo , Glándulas Suprarrenales/metabolismo , Animales , Encéfalo/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Masculino , Músculos/metabolismo , Miocardio/metabolismo , Conejos , Ratas , Bazo/metabolismo , Ácidos Esteáricos/metabolismoRESUMEN
Administration of alloxan to rats in a dose of 50-150 mg/kg raises blood sugar level from 200 +/- 14 to 800 +/- +/- 16 mg/100 ml. Under these conditions, the content of total gangliosides in the rat femoral muscle progressively decreases, namely from 137 +/- 9 micrograms sialic acid per g tissue to 63 +/- 4, which is linked with alloxan diabetes severity and hyperglycemia. At the same time there was a 3-4-fold inhibition of 14C-glucose oxidation intensity by tissue sections of the skeletal muscles in the presence of a 1.5-2-fold activation of 1-14C-palmitate. Fractionation of glycolipids on silica gel KSK demonstrated a 33% decrease in the content of monosialogangliosides, and a lesser diminution in the content of other fractions. Total muscle gangliosides, added to the incubation medium exogenously, produced a pathogenetic correcting action on disturbed oxidation of 14C-glucose in alloxan diabetes.
Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Glucolípidos/metabolismo , Músculos/metabolismo , Animales , Gangliósidos/metabolismo , Masculino , Oxidación-Reducción , Ratas , Ratas EndogámicasRESUMEN
Thin-layer chromatography on silica gel was used to identify individual gangliosides in the rat brain, cardiac, renal, spleen, pancreatic and skeletal muscles in health and to measure the content of sialic acid in the above organs. A dramatic decrease in mono-, di-, tri- and polysialoganglioside levels was seen in tissues of rats with alloxan diabetes. The data obtained indicate that insulin reception disorders may be provoked by the reduced content of acidic glycolipids in plasma membranes.