Age and strain comparisons of neurotransmitter synthetic enzyme activities in the mouse.
Activities of the neurotransmitter synthetic enzymes, choline acetyltransferase (EC 2.3.1.6; ChAT), glutamic acid decarboxylase (EC 4.1.1.15; GAD), and tyrosine hydroxylase (EC 1.14.3.2; TH), were assayed in four brain regions of A/J and C57BL/6J mice at three ages (4, 18, and 24 months). The brain regions assayed were the fronto-parietal cortex, hippocampus, striatum, and cerebellum. Strain effects: In some brain regions, at several ages, ChAT activity did not differ among the two strains. However, ChAT was higher in the C57BL/6J strain in the cortex at 18 months, the hippocampus at 18 and 24 months, the striatum at 24 months, and the cerebellum at 4 months. The reverse was true in the cerebellum at 24 months, where ChAT was higher in A/J mice. GAD activity in C57BL/6J mice compared to that of A/J mice was higher in the striatum and cortex, and lower in the hippocampus and cerebellum. TH activities in all four regions were generally higher in C57BL/6J mice than in A/J mice. Age effects: Age differences in enzyme activities varied with the genetic strain. ChAT activity generally was higher in brain regions of older mice of both strains.(ABSTRACT TRUNCATED AT 250 WORDS)
D000367:Age Factors; D000818:Animals; D001921:Brain / Q000201:enzymology*; D002795:Choline O-Acetyltransferase / Q000378:metabolism*; D005968:Glutamate Decarboxylase / Q000378:metabolism*; D007700:Kinetics; D051379:Mice; D008810:Mice, Inbred C57BL; D013045:Species Specificity; D014018:Tissue Distribution; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism*
D014446:Tyrosine 3-Monooxygenase; D002795:Choline O-Acetyltransferase; D005968:Glutamate Decarboxylase