Glutamate decarboxylase (GAD65) mRNA levels in the striatum and pallidum of MPTP-treated monkeys.
The mRNA levels encoding for the enzyme glutamate decarboxylase (GAD65) were measured by computerized image analysis after in situ hybridization histochemistry in the striatum and pallidum of normal and MPTP-treated squirrel monkeys. At striatal level, GAD65 mRNA labeling in MPTP-treated monkeys was primarily increased in the dorsolateral sector of the putamen. At pallidal level, the intensity of GAD65 mRNA labeling in single neurons was increased in the internal but not the external segment of the pallidum of MPTP-treated monkeys. The regulation of GAD65 mRNA levels in the striatum and internal segment of the pallidum suggest an important role for this enzyme in the regulation of GABAergic functions in basal ganglia.