[Acetylcholinesterase of subcellular structures of rabbit brain in ontogeny]

Subcellular fractions of the cerebral hemispheres of rabbits of different age groups are isolated by differential centrifugation in the sucrose gradient. The acetylcholinesterase activity of the fractions is also determined. It is found that in the postnatal period the specific activity of the enzyme increases in synaptosomes and pure mitochondria, is unchanged in the initial homogenate and in the subfraction of mieline fragments. The relative specific activity of acetylcholinesterase is unchanged in mitochondria, increases sharply in synamptosomes and decreases in the subfraction of myeline fragments. Changes in the specific and relative specific activity of acetylcholinesterase in the subcellular fractions of the developing brain are concluded to reflect the degree of functional maturation of cholinergic structures responsible for conducting the nervous impulse.