Acetylcholinesterase activity and its molecular forms in selected regions of the dog's nervous system.

Acetylcholinestrase (AChE, EC 3.1.1.7) activity and its molecular forms were studied in the cerebral cortex, basal ganglia, thalamus, cerebellar cortex, medulla oblongata, the various parts of spinal cord, the spinal ganglia and the sciatic nerve in intact adult dogs. The number and the proportion of different molecular forms of AChE in these regions of the dog's nervous system varied considerably. The highest AChE activity was found in the basal ganglia, where only one molecular forms was detected. Activity was also high in the cerebellar cortex (2 isoenzymes), the thalamus (4 isoenzymes) and the medulla oblongata (5 isoenzymes), and was lower in the cerebral cortex (3 isoenzymes). AChE activity in the spinal cord was highest in the sacral part (4 isoenzymes); in the other parts (3 isoenzymes) it was equal. Five molecular forms were found in the spinal ganglia and two in the sciatic nerve. The significance of the multiple molecular forms of AChE is discussed.