The aim of this article is to review the literature concerning the nature and function of the sympathetic innervation of the mammalian ovary. We focus our attention upon evidence relating to suggestions that ovarian smooth muscle participates in ovulatory events, and that such participation may be modulated by the local neural supply. Guttmacher & Guttmacher (1921) mentioned that this possibility was first suggested nearly 70 years before they observed smooth muscle‐like cells in the follicular walls of sow ovaries and found that isolated follicular walls were contracted by physostigmine and relaxed by adrenaline. However, Claessen (1947), using polarisation microscopy, was unable to confirm the presence of smooth muscle in the apices of follicles from a number of species, and interest in the Guttmachers' findings temporarily lapsed. In 1967, Jacobowitz & Wallach reported the findings of a histological study of ovaries from cats, monkeys and humans in which they observed catecholamine fluorescence associated with smooth muscle‐like cells in the stroma. In 1969, Rocereto, Jacobowitz & Wallach demonstrated that the cat isolated ovary exhibited spontaneous mechanical activity and was reactive to catecholamines. These investigations together with those of Owman & Sjöberg (1966) and Sjoberg (1967) initiated a resurgence of interest in the possibility that the adrenergic innervation of the ovary may play a functional role in ovarian processes; in particular that it might affect the contractility of smooth muscle and so participate in ovulation. With the development of techniques such as electron microscopy and fluorescence histochemistry, together with greater sophistication of pharmacodynamic analysis, an increasing number of publications concerned with the role of smooth muscle and adrenergic innervation in the ovary has appeared in the recent literature. Reference to some of this work is found in the reviews of Marshall (1972, 1973) and Bell (1972). A comprehensive review devoted specifically to the roles of catecholamines and nerves in ovulation was published by Bahr, Kao & Nalbandov in 1974. Their review described the sympathetic innervation of avian as well as of mammalian ovaries and the possible function of such innervation. They considered evidence relating to several possible roles, including modification of contraction of ovarian smooth muscle, participation in ovulation, and/or control of the ovarian vasculature, and concluded that nerves play some role in ovulation, but that it is not clear how this effect is mediated. Copyright © 1979, Wiley Blackwell. All rights reserved
