Effect of starvation or streptozotocin-diabetes on phosphate-activated glutaminase of different rat brain regions.
Phosphate-activated glutaminase (PAG) was assayed in homogenates of brain cerebellum, hippocampus or striatum from normal, starved for 48 h to 120 h or streptozotocin-diabetic rats. Only the hippocampal enzyme was increased (47%) by diabetes. Starvation had no effect in any of the regions studied. PAG of synaptosomes or of non-synaptosomal mitochondria from the hippocampus was also increased by 48% and 22% respectively in diabetes. PAG of synaptosomes from the cortex, the cerebellum, or the striatum or of the non-synaptosomal mitochondria from the cortex were not affected by diabetes or prolonged (120 h) starvation. A suggestion is presented that peripheral insulin, indirectly, may regulate PAG activity in a specific region of the rat brain.
Lellos
V
V
Laboratory of Biological Chemistry, School of Medicine, University of Athens, Greece.
Moraitou
M
M
Tselentis
V
V
Philippidis
H
H
Palaiologos
G
G
D000818:Animals; D001921:Brain / Q000201:enzymology*; D002531:Cerebellum / Q000201:enzymology; D003342:Corpus Striatum / Q000201:enzymology; D003921:Diabetes Mellitus, Experimental / Q000201:enzymology*; D004789:Enzyme Activation / Q000187:drug effects; D005972:Glutaminase / Q000378:metabolism*; D006624:Hippocampus / Q000201:enzymology; D008297:Male; D008928:Mitochondria / Q000201:enzymology; D010710:Phosphates / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013217:Starvation / Q000201:enzymology*; D013574:Synaptosomes / Q000201:enzymology
D010710:Phosphates; D005972:Glutaminase