Ganglioside treatment of diabetic rats; effects on nerve adenosine triphosphatase activity and motor nerve conduction velocity.
Ouabain-sensitive ATPase activity (expressed as nmol ADP produced/h/mg (wet) nerve +/- SEM) was measured in homogenates of sciatic nerve from control rats and rats with streptozotocin-induced diabetes of 8 wk duration. Nerves from diabetic rats showed activity (21.7 +/- 2.0) which was significantly (p less than 0.05) less than that of controls (34.6 +/- 4.8). These animals also showed a deficit in conduction velocity (m/sec +/- SEM) of sciatic nerve motoneurones (50.7 +/- 0.4 vs. 57.7 +/- 0.7 in controls; p less than 0.001). In parallel, matched control and diabetic groups were treated daily with mixed gangliosides extracted from bovine brain (10 mg/kg i.p.). After such treatment for 8 wk the deficit in ouabain-sensitive ATPase activity did not develop in the diabetic group (treated diabetics, 31.9 +/- 3.7; treated controls, 34.5 +/- 3.8). However, the treatment did not affect the deficit in motor nerve conduction velocity (treated diabetics, 50.9 +/- 1.1 vs. treated controls, 57.9 +/- 0.5; p less than 0.001). Accumulations of the polyol pathway metabolites--sorbitol and fructose--together with depletion of nerve myo-inositol were similar in both diabetic groups. These data indicate an etiology for the conduction velocity deficit which differs from that of the deficit in ouabain-sensitive ATPase.
Calcutt
N A
NA
Department of Physiology and Pharmacology, Medical School, Queen's Medical Centre, Nottingham, U.K.
Tomlinson
D R
DR
Willars
G B
GB
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy* / Q000201:enzymology / Q000503:physiopathology; D005732:Gangliosides / Q000494:pharmacology*; D008297:Male; D009046:Motor Neurons / Q000502:physiology*; D009431:Neural Conduction; D009434:Neural Pathways / Q000378:metabolism / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D012584:Sciatic Nerve / Q000201:enzymology* / Q000503:physiopathology
D005732:Gangliosides; D000251:Adenosine Triphosphatases