The age-dependent difference in the response of the vagina to the neonatal administration of testosterone propionate in Long-Evans female rats

Summary The ability of the vaginal epithelium to respond to testosterone propionate by producing keratin was established when female rats were 3 days of age, whereas the vaginal stroma from rats 2 days old or less was capable of responding to the androgen and might destroy the vaginal epithelium.     

Application vaginale de cystamine et Radio-Protection locale

Summary In a previous paper, the authors showed that intraperitoneally administered cystamine protects the vaginal mucosa of rats against local irradiation.Using the same technique (study of radiation-lesions in vaginal smears), they demonstrate that locally administered cystamine is also effective.     

Deciduoma formation in rats with cornified vagina

Summary In female rats given a single injection of 1.25 mg 5-dihydrotestosterone during neonatal life, reactivity of the vaginal mucosa to hormones was permanently altered, so that the rats, when adult, could show vaginal cornification under the hormonic conditions supportive of development of deciduomata in the uterus.We wish to thank Prof.T. Kimoto of Kawasaki Medical College for valuable advice and information.     

Sexual maturation in female rats: hereditary, developmental and environmental aspects

Two physiological components of sexual maturation, vaginal opening and first estrus, apparently evolve similarly in Wistar and Sprague-Dawley rats. However, a bimodal distribution in the frequency of the days of vaginal opening is observed within a given strain, which is less related to heredity than to the timing and type of experiment. In addition, when the modulators of sexual maturation are reviewed, it can be observed that sensitivity to external stimuli can vary even within a strain. For a defined set of breeding conditions, one group of rats can be more susceptible to changes in the lighting regimen and not be affected by controlled stressors, while another group responds more to stress and less to light. The reason for susceptibility to one rather than another environmental factor under similar breeding conditions is not understood. In that context, it is difficult to evaluate the role of heredity when we cannot understand the full impact of the environment, not to mention maternal influence in fetal and early life. Using two lines of psychogenetically selected rats, it was possible to show that they had differences in sexual maturation, which strongly suggested a genetic predisposition. Nevertheless, the question arises as to whether the genetic locus directly affects organs implicated in sexual maturation or whether it acts on some unknown factor which only secondarily modifies sexual maturation. In summary, there is more need to understand the role of the environment, including that of the mother early in fetal and neonatal life. It is suggested that the mechanisms underlying organ growth are set for a given species, while developmental and environmental factors fix the timing of vaginal opening and first ovulation. In the rat, there appear to be two times which are preferred for vaginal opening, given the laboratory conditions that have been used in the last 20 or so years: an early period, at 31-35 days, and a late period, at 36-40 days. An explanation for this dichotomy would be that a combination of parameters (not necessarily always the same) is needed for vaginal opening. These parameters oscillate during sexual maturation with different frequencies, which can achieve resonance to lead to vaginal opening and ovulation only during given periods.     

Sexual maturation in female rats: Hereditary,developmental and environmental aspects

Two physiological components of sexual maturation, vaginal opening and first estrus, apparently evolve similarly in Wistar and Sprague-Dawley rats. However, a bimodal distribution in the frequency of the days of vaginal opening is observed within a given strain, which is less related to heredity than to the timing and type of experiment. In addition, when the modulators of sexual maturation are reviewed, it can be observed that sensitivity to external stimuli can vary even within a strain. For a defined set of breeding conditions, one group of rats can be more susceptible to changes in the lighting regimen and not be affected by controlled stressors, while another group responds more to stress and less to light. The reason for susceptibility to one rather than another environmental factor under similar breeding conditions is not understood. In that context, it is difficult to evaluate the role of heredity when we cannot understand the full impact of the environment, not to mention maternal influence in fetal and early life. Using two lines of psychogenetically selected rats, it was possible to show that they had differences in sexual maturation, which strongly suggested a genetic predisposition. Nevertheless, the question arises as to whether the genetic locus directly affects organs implicated in sexual maturation or whether it acts on some unknown factor which only secondarily modifies sexual maturation. In summary, there is more need to understand the role of the environment, including that of the mother early in fetal and neonatal life. It is suggested that the mechanisms underlying organ growth are set for a given species, while developmental and environmental factors fix the timing of vaginal opening and first ovulation. In the rat, there appear to be two times which are preferred for vaginal opening, given the laboratory conditions that have been used in the last 20 or so years: an early period, at 31–35 days, and a late period, at 36–40 days. An explanation for this dichotomy would be that a combination of parameters (not necessarily always the same) is needed for vaginal opening. These parameters oscillate during sexual maturation with different frequencies, which can achieve resonance to lead to vaginal opening and ovulation only during given periods.     

Effect of an LH-RH antagonist on reproductive status of immature female rats.

Administration of the LH-RH antagonist, D-Phe2-D-Ala6-LH-RH (Wy-18, 185) to immature female rats from days 25--35 of age was without significant effect on day of vaginal opening (puberal onset), weights of the ovaries, uteri and anterior pituitary, and on ovarian histology on autopsy day 39.     

Effects of postnatal progesterone treatment on ovarian function in adult rats

Summary Long-lasting postnatal progesterone administration in female rats induced an early or delayed ovulatory failure with persistent vaginal estrus. Short-term treatment was ineffective. The beginning and incidence of ovulatory failure appeared to depend on the beginning and duration of progesterone treatment. The necessary duration of progesterone administration exceeds the critical postnatal steroid sensitive period of sexual differentiation of the hypothalamus. Moreover, long-lasting progesterone treatment results in ovulatory failure even if started after termination of this period.     

Effects of postnatal progesterone treatment on ovarian function in adult rats

Long-lasting postnatal progesterone administration in female rats induced an early or delayed ovulatory failure with persistent vaginal estrus. Short-term treatment was ineffective. The beginning and incidence of ovulatory failure appeared to depend on the beginning and duration of progresterone treatment. The necessary duration of progesterone administration exceeds the critical postnatal steroid sensitive period of sexual differentiation of the hypothalamus. Moreover, long-lasting progesterone treatment results in ovulatory failure even if started after termination of this period.     

Bromocryptine treatment and puberty attainment in the female rat

Summary The influence of bromocryptine treatment on the timing of vaginal patency and 1st oestrus in female rats was studied. No significant influence of bromocryptine on these parameters was noted, and it is concluded that suppression of prolactin secretion has no effect on puberty attainment.Acknowledgment. We thank Professor E. Flückiger and Dr H. Friedli, Pharmaceutical Division, Sandoz Ltd, Basle, Switzerland, for the donation of bromocryptine mesylate.     

Effect of an LH-RH antagonist on reproductive status of immature female rats

Summary Administration of the LH-RH antagonist, D-Phe²-D-Ala⁶-LH-RH (Wy-18, 185) to immature female rats from days 25–35 of age was without significant effect on day of vaginal opening (puberal onset), weights of the ovaries, uteri and anterior pituitary, and on ovarian histology on autopsy day 39.The technical expertise of J. Tracy is gratefully acknowleged.     

The effect of clomiphene citrate and estradiol on body weight,vaginal cornification,and uterine weight after chronic treatment of ovarlectomized rats

Summary Clomiphene reduced the body weight gain of ovariectomized rats to a much greater degree than extradiol did. Estradiol had a more pronounced effect on vaginal cornification and uterine weight than clomiphene did.Acknowledgment. The work was supported by USPHS Grant AM-08029-6 awarded to Dr W. J. Bo. The support and guidance of Dr Bo is gratefully acknowledged. The clomiphene citrate was generously supplied by the Wm. S. Merrell Co., and the estradiol by Ciba Pharmaceutical Co.     

Leucocyte invasion of the vaginal epithelium in the absence of bacteria in mice

Summary Influx of leucocytes in the vagina at metoestrus occurs in germfree mice and also in sterile isotransplants of vaginal tissue in conventional mice. In contrast to the situation in rats, bacteria thus do not seem to be required for the production of postovulatory leucotactic stimuli in the vagina.Acknowledgments. Data with germfree mice could be obtained through the generous cooperation of Prof. Dr F. Wensinck and Dr M. P. Hazenberg (Dept. Medical Microbiology, Erasmus University), C. Lekkerkerker and J. ten Veen (TNO, Zeist, The Netherlands). The skillfull cooperation of Miss P. D. M. van der Vaart and Mrs A. Verschoor-Burggraaf is gratefully acknowledged.     

Gamma globulins in the mice vaginal fluids: cyclic and experimental variations.

The study of the gamma globulins in the vaginal fluids reveals that the lowest values were found in mice at estrus and in castrated mice 8 days after the estrogen treatment. We suggest that the variation of gamma globulins in the vaginal fluids is influenced both under physiological and experimental conditions by estrogens.     

De l'action radio-protectrice exercée sur la muqueuse rectale par la cystéamine administrée par voie générale et par la cystamine administrée par voie intra-rectale

Summary The authors studied the lesions observed in the rectal and vaginal smears of the rat after a local irradiation of the rectum. They observed that an injection of cysteamine before the irradiation strongly diminishes the ratio of damaged rectal and vaginal cells. A local treatment with cysteamine in the rectum before and during the irradiation diminishes only the ratio of damaged rectal cells.     

Antagonistic effect of progesterone towards estradiol dipropionate-induced changes in glycogen content in uterus and vagina of P-mice

Summary Estradiol dipropionate induces an increase (3-fold) in the uterine glycogen content and a decrease (4-fold) in the vaginal glycogen content of Parkes (P) mice. Progesterone antagonizes this estradiol dipropionate-induced response in both the uterine and vaginal tissue. The degree of this antagonism is more pronounced in the uterus than in the vagina.Acknowledgments. The authors are extremely grateful to Prof. C.J. Dominic for his suggestions and guidance during experimentation.     

Gamma globulins in the mice vaginal fluids: Cyclic and experimental variations

Summary The study of the gamma globulins in the vaginal fluids reveals that the lowest values were found in mice at estrus and in castrated mice 8 days after the estrogen treatment. We suggest that the variation of gamma globulins in the vaginal fluids is influenced both under physiological and experimental conditions by estrogens.This work was supported by a grant of the Conicet No. 4973 b/74.Fellow of Scientific Investigator Career. Consejo Nacional de Investigaciones Cientificas y Técnicas.Member of Scientific Investigator Career. Consejo Nacional de Investigaciones Científicas y Técnicas.     

Morphological alterations of basal cells of vaginal epithelium in neonatally oestrogenized mice

Summary Neonatal oestrogen treatment results in the development of vaginal cancers in the mouse. A morphological sign which probably indicated early invasion of altered vaginal cells into the stroma through gaps in the basal lamina was first seen at 10 months of age in neonatally oestrogenized C57Black mice. Prior to this, a decrease in the numbers of cellular attachment organelles such as half desmosomes and desmosomes was observed by 3 months.This work was supported by Contract NO1-CP-55650 of National Cancer Institute, National Institute of Health, Public Health Service, USA, and by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture of Japan.     

Elektronenmikroskopischer nachweis von langerhansschen zellen im epithel normaler menschlicher vagina

Summary Typical Langerhans cells were demonstrated in the normal human vaginal epithel by electron- microscopic means.     

Ketoconazole -- a new broad spectrum orally active antimycotic.

Oral treatment with ketoconazole prevented and cured artificial crop candidosis of the turkey, vaginal candidosis of the rat and skin candidosis of the guinea-pig. It was also highly effective against artificial systemic candidosis of the guinea-pig and chicken as well as against dermatophytoses of the guinea-pig.     

Embryonic death in mouse due to lead exposure.

Female mice which displayed a vaginal plug after mating were given a diet containing 0, 0.125, 0.250, 0.500% of lead as lead acetate and were dissected 16 to 18 days later. Lead treatment was found to reduce significantly the incidence of pregnancies and to increase the postimplantation loss in the pregnant females.