A HISTOCHEMICAL STUDY OF OVARIAN CHOLINESTERASES

Abstract

Cholinesterases were demonstrated histochemically in the ovaries of rat, guinea pig, rabbit and monkey, and characteristed by the use of differential inhibitors. The rat and guinea pig ovaries show marked BuChE activitiy in granulosa cells and fibers of the theca externa, while in the rabbit the predominant reaction is in intersitial cells. In the monkey ovary there is strong BuChE activity in network consisting both of nerve fibers and blood capillaries. In the rat, rabbit and guinea pig ovaries occasional nerve fibers are shown in uninhibited acetyl thiocholine preparations, but their reaction isabolished by the use of BuChE inhibitors. Uninhibited acetyl thiocholine preparations of monkey ovary show a rich innervation, arranged in perivascular and perifollicular plexuses. Only a proportion of the fibers seen in uninhibited sections are demonstrated after the use of a BuChE inhibitor. It is possible that the inhibitor permits the demonstration only of cholinergic nerves, but it is difficult to understand why a similar cholinergic innervation cannot be deomonstrated in the rat, guinea pig and rabbit ovaries.