Regional variations of choline-acetyltransferase in the chick embryo optic lobe

The specific activity of CAT and AChE was determined in different regions of the chick embryo optic lobe at several stages of development. Regional differences in CAT activity appeared in 9-day-old tectum, being the posterobasal area the one with higher enzymatic activity. On the other hand, at 6th and 13th day of development, the levels of AChE and CAT are similar throughout the optic lobe.