On the Endocrine Basis of Mating in the Mouse

Abstract

I. THE question as to the causes of heat has been frequently considered. While earlier authors assumed a nervous stimulus originating in the ovary to be responsible for the induction of heat, recent investigators are of the opinion that an ovarian hormone incites the readiness for mating which, as a rule, only occurs during certain stages of the cestrous cycle. This conception has gained prominence since ALLEN and DoisY showed that the typical morphological changes of the cestrous cycle in rat and mouse can be incited in ovariotomised animals by the injection of certain ovarian and placental extracts, and also reported that in some of the injected animals mating occurred. Many of the numerous investigators who have studied the effects of the ALLENDoisY factor have referred to it as the "female sex hormone," although they concerned themselves mainly or exclusively with its morphological actions, and did not consider the sexual behaviour of the animals. Moreover, several of the investigators who observed their animals for the occurrence of mating noticed that only a certain percentage mated. The percentage of copulation reported by PARKES was 7-6 (mice); in this percentage only those animals are included in which cornification had occurred under the influence of the extracts. It is obvious that cornification of the vaginal epithelium and cestrus are not only two essentially different phenomena, but also that the former is not necessarily an indication of the latter. The relatively small percentage of mating induced by injections of ovarian extracts made it, moreover, doubtful whether the same conditions are responsible for mating and the morphological changes accompanying it. One of the present authors (B. P. W.) observed that no case of mating occurred in the course of an experiment in which cornification was induced in forty-three ovariotomised rats by extracts of cow's placenta; HEMINGSEN, on the other hand, reported that three spayed mice mated without having received injections and without having regenerated ovaries. It was

Modular Genetic Control of Sexually Dimorphic Behaviors

“…Castration rapidly eliminates estrous cycling and female sexual behavior (Allen and Doisy, 1923; Wiesner and Mirskaia, 1930; Ring, 1944), and we compared gene expression between adult castrate females and controls. In contrast to the wholesale changes in gene expression in male castrates, we observed highly circumscribed changes in castrate females.…”

Studies on the oestrus‐producing hormone (oestrin)1

“…Marrian and Parkes (1930) found that the number of spayed mice showing vaginal plugs increased with an increasing dose of oestrin, but even with 200 mouse units only 9 out of 19 animals had copulated. Similarly Wiesner and Mirskaia (1930) found that even 280 mouse units did not produce insertion of plugs in more than 11 out of 20 spayed mice. Zondek (1931, p.92) states that spayed mice and rats injected with oestrin are recognized by the buck as being in heat and are pursued by the buck.…”

“…Further Evans and Bishop (1922), Evans (1928), and Reiss and Per eny (1928), have shown that cornification of the vaginal epithelium is continuous, both in normal and ovariectomized females, on a diet deficient in vitamin A, although no oestrin has been administered. This result of avitaminosis must be considered in the light of the investigations of Wolbach and Howe (1928), who find that the specific effect of vitamin A deficiency is the substitution of cornified for normal epithelium of all mucous surfaces of the body.…”

Evolutionary changes in the physiological control of mating behavior in mammals.

“…Ovariectomy of prepuberal rats, guinea pigs, rabbits, and other lower mammals precludes the occurrence of mating responses in adulthood (117), and similar operation after the attainment of reproductive maturity promptly and permanently abolishes all manifestations of sexual heat in rodents (60,103,112), ungulates (3,78) and carnivores (8,66,68,71). Regardless of the age at operation, it is possible to bring out normal coital responses in the ovariectomized female during adulthood by the injection of the appropriate ovarian hormones.…”