ISSN:0003-276X    

DOI:10.1002/ar.1091570102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

ISSN:0003-276X    

DOI:10.1002/ar.1091570103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThe 10‐day old natural young of lactating rat mothers were removed, and the mother was given newborn foster young together with hormone treatment. A single injection of prolactin or progesterone was sufficient to increase the survival perentage and body weight of the fostered rats. An hypothesis is presented to explain the action of the hormones and the possible relationship to placental eating which is noted in many mammals at the time of parturitio

ISSN:0003-276X    

DOI:10.1002/ar.1091570104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractAntiserum to human chorionic gonadotropin (anti‐HCG) with measured capacity to inhibit its antigen was used in conjunction with HCG in intact immature and in hypophysectomized female rats to determine if this hormone has intrinsic follicle stimulating properties. In intact rats, 100, 200, 500, 1000, 1500, 2000 and 2500 I.U. of HCG were given alone and in conjunction with anti‐HCG. In hypophysectomized rats, 400, 800, 1600, 3200, and 6400 I.U. of HCG were given alone and with anti‐HCG. Anti‐HCG inhibited both the second rise in ovarian weight in intact females and follicular development in hypophysectomized females in a manner anticipated on the basis that these responses depended upon the HCG molecule. In hypophysectomized females inhibitition of follicular growth preceded inhibition of interstitial cell development. This result is also in accord with the view that both of these responses depend upon the HCG molecule.The anti‐HCG serum did not inhibit synergism between HCG and NIH‐FSH‐S1, an ovine pituitary FSH, with doses of 100 and 200 I.U. of HCG combined with 240 m̈g of FSH. An amount of antiserum which would inhibit 500 I.U. of HCG augmented rather than inhibited the response to 1000 μg of NIH‐FSH‐S1 (43 mg ovarian weight as compared to 29 mg).We conclude from these data that the HCG molecule has intrinsic follicle sti

ISSN:0003-276X    

DOI:10.1002/ar.1091570105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractA study of sex differentiation of the Wolffian and Müllerian ducts of fetal guinea pigs was made by an organ culture method, and the morphogenetic changes of the ductsin vitrowere compared with thosein vivo. A total of 19 reproductive tracts were explanted from fetuses 29‐30 days old. The explants were cultured for nine days, with or without gonads. The Wolffian ducts degenerated in male tracts cultured without testes and in female tracts with or without ovaries, but they were maintained in male and female tracts cultured with one or two testes. The Müllerian ducts degenerated in all male tracts; in female tracts with or without ovaries they enlarged and coiled extensively and they were not inhibited when testes were cultured with the female tracts. It is concluded that in the guinea pig fetus at 29‐30 days of age, the Wolffian ducts of both sexes have become androgen‐dependent and that they are normally maintained in the male by testicular androgen. The Müllerian ducts of males were conditioned to degenerate before the time of explantation. The Müllerian ducts of females were not dependent upon ovarian hormone for their maintenance and de

ISSN:0003-276X    

DOI:10.1002/ar.1091570106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractA schematic plan of late developmental organization of the fetal cotyledonary elements of the hemochorial placenta is presented. It involves mechanical shaping by hemodynamics and stretching of the elements involved in the late chorion frondosum stage after the2ndmonth of gestation. The result is the fetal cotyledon as described by Wilkin. The components of the fetal cotyledon are derived from differentiated vascular elements in tertiary stem, or anchoring, villi and vascular elements of the blastoderm which are formed by the twenty‐first day after ovulatio

ISSN:0003-276X    

DOI:10.1002/ar.1091570107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractPreviously it had been demonstrated that daily injections of testosterone propionate (T.P.) will not induce male‐like mounting nor clitoral hypertrophy in pregnant guinea pigs to the extent it will in non‐pregnant females. In addition, administered progesterone had been shown effective producing a similar behavioral, but not somatic, “protection.” In an attempt to clarify the relationships of endogenous progesterone producing organs and this antiandrogen protective phenomenon the behavioral and somatic responses of females ovariectomized while pregnant and females hysterectomized (made pseudopregnant) while non‐pregnant were studied.Guinea pigs were hysterectomized on the sixth day of their ovarian cycle and ovariectomized 60 days later. Additional groups of females were mated and then ovariectomized on the thirty‐sixth or forty‐sixth day of gestation. Groups of normal pregnant females, aborted females, and sham operated controls were also studied.All groups received daily injections of T.P. starting on the eighteenth day of pregnancy and continuing for the duration of the experiment (116 days). With these androgen treatments masculinization or protection from maculinization was evaluated on the basis of periodic sex behavior tests and on the basis of daily inspection of the external genitalia.The results indicate that protection from testosterone propionate‐induced virilization is offered by exogenously administered progesterone as well as by an endogenous progestagen‐producing structure such as the corpora lutea of the ovary in a hysterectomized female or the placenta in a pregnant animal. Some factor other than progesterone production is involved and the neural and somatic tissues exhibit different re

ISSN:0003-276X    

DOI:10.1002/ar.1091570108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractA review is presented of the effects of steroids having hormone‐like activity upon the following reproductive processes in mammals: (a) spermatogenesis, (b) ovulation, (c) fertilization, (d) oviducal and uterine travel of the free ovum, and (e) blastocyst growth and implantation. Description is given of a number of natural and synthetic steroids which inhibit spermatogenesis and ovulation. By and large, estrogens are especially effective in the former and progestins in the latter, but aparently some species differences in response to potent substances do exist. Progestins have been shown to inhibit fertilization in experimental animals either through an effect on sperm travel or on sperm capacitation. The rapid expulsion of eggs from the fallopian tubes is accomplished by a variety of synthetic and natural estrogens upon administration in significant dosage in test animals. Decidualization and other processes related to implantation are also steroid labil

ISSN:0003-276X    

DOI:10.1002/ar.1091570109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractCastration of the male rat during the first three days of life allows retention of the cyclic pattern of gonadotrophin release with which the male is born. Since the neonatally castrated male shares several endocrine characteristics with the female, the terms feminine male or FALE have been employed to identify these animals. Twenty‐seven of 28 FALES developed corpora lutea (CL) in ovarian transplants provided no other treatment was initiated. In contrast, exposure to constant illumination, suprachiasmatic lesions, or transection of anterior hypothalamic pathways prevented CL formation in 18 of 20 FALES. These findings support the concept that the preoptic‐anterior hypothalamic region is an essential component of the neural mechanism which regulates the cyclic luteinization of ovarian grafts in the FALE. Since the FALE is a male rat in which differentiation has not been permitted to occur, it is suggested that sexual differentiation of the normal male hypothalamus consists of an alteration in function of this preoptic sys

ISSN:0003-276X    

DOI:10.1002/ar.1091570110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY

摘要:

AbstractThe post‐natal development of penile spines, their appearance in adult males, and the changes that occur in them after castration, after treatment of castrated males with testosterone propionate, and after cessation of hormone treatment were studied using both pre and postpuberal castrates. Most of the observations were made on live animals and the conditions of the spines were correlated with levels of sexual activity using data from mating tests with estrous females. In all the conditions of testing, the spines increased in size as the androgen level increased, and decreased in size as the androgen level fell. These changes correlated positively with the rise and depression of mating activity as the androgen levels increased or decreased. The relationship, however, was not always consistent in that sexual behavior declined rapidly in some castrated males before the spines started to decrease in size, and in other castrated males, sexual behavior persisted long after the spines had disappeared. While our data are not inconsistent with the hypothesis that loss of spines leads to reduced stimulation of the penis during intromission and hence to a decline in sexual arousal, it emphasizes that the great variability in sexual behavior after castration must be due to other cause

ISSN:0003-276X    

DOI:10.1002/ar.1091570111

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1967

数据来源: WILEY