Serum glutamic acid decarboxylase activity in normal dogs.

Serum concentrations of glutamic acid decarboxylase, a nearly brain-specific enzyme, were determined in 290 samples from 29 normal Beagle dogs, using a modification of a fluorometric method. Mean glutamic acid decarboxylase activity was 214 micromoles/hr/L (units). Seemingly, 95% of clinically normal Beagles would have values between 93 and 335 units and 99% of the values would fall between 50 and 378 units.