Effect of progesterone on male and female sex behavior induced by steroid hormones in adult ovariectomized ewes]

Ovariectomized adult Ewes daily treated with I/M injections of testosterone propionate (10 mg/day) or oestradiol benzoate (200 microgram/day) show male-like sexual behaviour and simultaneously a permanent female receptivity. Additional daily treatment with 100 mg of progresterone results in a rapid decrease in male sexual responses both when Ewes are treated with testosterone and with oestradiol. No effect is observed on the female receptivity. Cyproterone acetate (100 mg/day) given to Ewes in addition to daily injection of testosterone propionate (10 mg/day) has effects similar to those of progesterone. These results show that progesterone has antiandrogen and antioestrogen properties and that this hormone administered at high doses is able to inhibit male activity.     

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.     

Steroid-induced concentric membrane whorls in dog liver

Summary When daily doses of 10 mg/kg of the androgenic steroids fluoxymesterone, methyltestosterone, testosterone propionate, oxymetholone and mepitiostane were administered to adult male and female beagle dogs for 6 months, concentric membrane whorls were produced in the hepatocytes of all groups. The whorls frequently had a central core mainly composed of lipids or mitochondria and the membranes of the whorls, consisting of paired membranes, continued to the smooth or granular endoplasmic reticulum at the periphery of the structures.     

An early effect of testosterone propionate upon hypothalamic function in the neonatal rat

Rats treated neonatally with testosterone propionate exhibit a reduced uterine growth response to estradiol administration prepubertally. This androgen-induced impairment is the consequence of developmental effects on both the ovary and the hypothalamic-pituitary complex, although the latter is the more sensitive.     

Effect of actinomycin D or puromycin on microsomal testosterone hydroxylase activity enhanced by testosterone in female rat liver

Summary The injection of testosterone propionate for 4 successive days into female rats resulted in an increase of the in vitro conversion of the hydroxylated testosterones from testosterone by the hepatic microsomal, fraction, but no change in the content of microsomal cytochrome P-450 occurred. Actinomycin D or puromycin, which was administered for 4 days with injections of testosterone propionate, prevented the enzyme induction.     

Induction of vitellogenin by estradiol and androgens in a teleostean fish: Gobius niger L]

At any point in the sexual cycle of both males and females, oestradiol benzoate induces synthesis of plasmatic vitellogenin, identifiable by a specific immunserum. Pharmacological doses of purified testosterone and dihydrotestosterone also induce synthesis of this yolk precursor. Although a partial aromatisation of testosterone into oestrogen is possible, our results show that there must also be interaction between the androgens and the oestrogens receptors in the liver.     

Effects of testosterone propionate on LH and testosterone concentrations before and after the injection of gonadoliberin in young bulls pre-treated with dexamethasone]

This preliminary study has been performed on four young twin bulls, one pair aged 6 months and the other one aged 12 months. Plasma LH and testosterone were assayed from frequent blood sampling. Testosterone propionate (TP) following dexamethasone treatment did not significantly influence the LH response to gonadoliberin compared to the twin controls, although testosterone concentrations were high in those TP treated animals.     

The effect of daily evening isoproterenol administration on reproductive organ growth in male rats treated neonatally with testosterone propionate

Summary Daily evening injections of isoproterenol extended the period of high pineal N-acetyltransferase activity and retarded the growth of testes, seminal vesicles and prostate in rats treated neonatally with testosterone propionate.The authors are grateful to Mrs Marie Svobodová for her skillful technical assistance.     

Transaminasenaktivität nach Methyltestosteron-, Testosteronpropionat-, Chlorpromazin- und Methylthiouracilbehandlung

Summary The treatment of 62 patients with chlorpromazine was followed by a rise of SGO-T in the serum in 20% of them. Six other patients were treated with a daily dose of 200 to 400 mg Methylthiouracil for 14 days. No elevation of serum transaminases was observed. The application of a daily dose of 30 mg methyl testosterone to 40 other patients was followed by a rise of SGO-T and SGP-T in 77% of them. The maximal elevation of SGO-T was 275 U. and of SGP-T 260 U., and this was reached during 10 days of therapy on an average. This effect is bound to the methyl group of methyl testosterone, since in 10 patients, treated with the same dose of testosterone propionate, the serum transaminases activity were not influenced.     

Splenic thymidine kinase and DNA during early postnatal development of the androgenized female rat

Administration of a pharmacologic dose of testosterone propionate to neonatal female rats had no effect on either thymidine kinase activity or DNA synthesis in the spleen during the first 3 postnatal weeks.     

Treatment of pregnant rats with haloperidol delays the onset of sexual maturation in female offspring

Summary Treatment of pregnant rats with haloperidol (1 mg/kg/day) during the last week of gestation induces a significant delay in sexual maturation of female offspring.This study was supported by a Canadian MRC grant, No. MA-7131.     

Inhibition of post-hemicastration hypertrophy of the remaining testis by testosterone or aqueous testicular extract treatments in the young rat]

In the 10 day old hemicastrated Rat daily injections of testosterone (total doses of 0.04 to 4 mg/Rat) or of proteinaceous extract of Rat testis (4 mg/Rat) inhibit compensatory hypertrophy of the remaining testis. Both testosterone and testicular proteinaceous extract could be involved in the growing processes of the testis, locally or by means of modification of gonadotropin secretion. Results have been analysed by covariance analysis to eliminate the influence of body weight variations.     

Plasma testosterone concentration in control and testosterone-treated chick embryos.

After testosterone propionate treatment (1 or 2 mg per embryo), plasma testosterone in chick embryos rises to 500 times higher than in control animals, and then progressively diminishes during the following days of incubation. These drastic changes in hormonal status after the TP treatment entails consequences that may be considered pharmacological rather than physiological.     

Inhibitory action of estradiol on testosterone production in rat embryo]

Embryos from Rats given an injection of 0,5-1 mg of oestradiol benzoate on days 17--19 of pregnancy show a 3--4-fold reduction in their testicular testosterone content with respect to the control embryos, 24--48 hrs later. OEstradiol most likely acts by inhibiting LH secretion, which in turn results in a lowered testosterone production.     

Levels of testosterone and dihydrotestosterone in guinea pig sex canals during embryonic life]

At the undifferentiated stage, testosterone and dihydrotestosterone levels were comparable in sexual ducts of both sexes. An hormonal sexual dimorphism appeared at the time of differentiation: while testosterone rapidly decreased in the female ducts, it considerably increased in those of the male. Testosterone rather than DHT seems to be responsible for the wolffian duct stabilization in the male foetus.     

Sex difference in polyethylenglycol-induced thirst

Summary The polyethylenglycol-induced thirst in male and female castrated rats has been studied. The polyethylenglycol (PG) increases the water intake more in females than in males. Estradiol benzoate and testosterone P. diminishes the amount of water drunk after PG treatment in the females, but not in the males.     

Seasonal variations in the nyctohemeral rhythm of plasma testosterone in the European badger Meles meles L

In the badger a seasonal sexual rhythm of the plasma testosterone is observed. There is also a nycthemeral rhythm of the testosterone secretion; during the regressed period of the testis this rhythm is bimodal with testosterone peaks during the light phase of the day; during the active period and "activity rhythm" with many transitorys peaks during the dark phase is added.     

Evolution of testosterone and dihydrotestosterone in plasma, testicle and ovary of the guinea pig throughout fetal life]

High testosterone concentrations were found in the plasma of male fetus at the stage of sexual differentiation. Then the fetal testis is the principal source of circulating testosterone; its action on the Wolffian duct would occur by the systemic pathway. In female fetus, androgens were synthesized by the gonad and the relatively high levels found in the plasma have probably another source.     

Plasma testosterone concentration in control and testosterone-treated chick embryos

Summary After testosterone propionate treatment (1 or 2 mg per embryo), plasma testosterone in chick embryos rises to 500 times higher than in control animals, and then progressively diminishes during the following days of incubation. These drastic changes in hormonal status after the IP treatment entails consequences that may be considered pharmacological rather than physiological.Acknowledgment. We would like to thank Mrs N. Jeanguyot (UNCEIA, Laboratoire d'hormonologie, Maisons Alfort, France) for her excellent technical assistance in the RIA procedure.     

Effect of a steroid contraceptive, "Enidrel" on the pre- and postnatal development of rats

To determine the long-term effects of prolonged and intensive treatment with an anticonceptive steroid, 60 female Wistar rats were given 1 mg/kg/day Enidrel (norethynodrel plus ethinyl estradiol 3-methyl-ether) by gastric sound for 60 days. The animals were divided into 2 groups and were placed with males for 10 days. Group 1 continued to recieve Enidrel through mating to the 15th day of gestation; Group 2 received no further treatment. General behavior and weight of the animals was unchanged when compared with controls. There were profound disturbances in the estrous cycle, but couplings and number of impregnations were normal in both groups. Most of the females in Group 1 aborted normal fetuses between Gestation Days 8 and 15; those in Groups 2 continued to term. Group 1 animals were remated and siblings of the 1st generation were crossed. The animals were fertile and the ne onates developed normally. It is concluded that Enidrel had no effect on morphogenesis and no masculinization effect on the hypophyso-hypothalamic system, as evidenced by the normal sexual behavior and fertility of the females.