Cholinesterase activity in the corpus luteum of the sheep and pig.

The acetylcholinesterase (AHhE) activity in the corpora lutea of ovaries from sheep has been examined at different stages of pregnancy and the oestrous cycle, by both quantitative and histochemical techniques. The enzyme activity rose during the early part of pregnancy and then levelled out; it appeared to fall sharply at term. During the oestrous cycle the AChE activity was much lower but showed time-related changes. A few results from pigs and cows are included. The cows corpora lutea, unlike those of the sheep and pig contained butyrylcholinesterase (BuChE) as well as AChE. The results are discussed in terms of the possible function of non-neuronal cholinesterases.