Zinc and glutamate dehydrogenase in putative glutamatergic brain structures.
A certain topographic parallelism between the distribution of histochemically (TIMM staining) identified zinc and putative glutamatergic structures in the rat brain was demonstrated. Glutamate dehydrogenase as a zinc containing protein is in consideration to be an enzyme synthesizing transmitter glutamate. In a low concentration range externally added zinc ions (10(-9) to 10(-7) M) induced an increase in the activity of glutamate dehydrogenase (GDH) originating from rat hippocampal formation, neocortex, and cerebellum up to 142.4%. With rising molarity of Zn(II) in the incubation medium, the enzyme of hippocampal formation and cerebellum showed a biphasic course of activation. Zinc ions of a concentration higher than 10(-6) M caused a strong inhibition of GDH. The effect of Zn(II) on GDH originating from spinal ganglia and liver led only to a decrease of enzyme activity. These results are discussed in connection with a functional correlation between zinc and putatively glutamatergic system.
D000818:Animals; D001921:Brain / Q000201:enzymology; D001923:Brain Chemistry; D002531:Cerebellum / Q000201:enzymology; D005969:Glutamate Dehydrogenase / Q000378:metabolism*; D005971:Glutamates / Q000378:metabolism; D018698:Glutamic Acid; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013194:Staining and Labeling; D015032:Zinc / Q000032:analysis*
D005971:Glutamates; D018698:Glutamic Acid; D005969:Glutamate Dehydrogenase; D015032:Zinc