Sexual motivation in the female rat after testosterone treatment

The effect of testosterone propionate (TP) on sexual motivation in the ovariectomized female rat was studied. The urge to seek sexual contact was measured in terms of location in the male vicinity in an open field, the amount of aversive stimulus (crossing of an electric grid) the animal was willing to take to seek contact with a sexually active male and the preference in a run and choice situation for a sexually active male versus a female. It was a consistent finding in the three different methods used that TP 1 mg/kg induced a significant increase in the willingness of ovariectomized rats to seek contact with a sexually active male. A sexually active male was more incentive than a castrated male or a female. The effect of TP was dose-dependent and the maximal response occurred after 2–4 days.     

十一酸睾酮制剂对中老年勃起功能及男性性激素水平的影响

目的：观察口服睾酮制剂对中老年男子睾酮部分缺乏综合征(PADAM)勃起功能及激素水平的影响。方法：对42例拟诊PADAM者，口服十一酸睾酮胶囊，治疗前后观察血清E2、T，勃起功能指数，前列腺大小及尿流率。结果：治疗16周后，血清雄激素、勃起功能指数较治疗前有明显好转，雌激素水平、尿流率无明显变化。结论：对性激素水平低下的中老年男子，雄激素治疗，可以升高睾酮水平，改善性功能及生活质量。     

青春期胰岛素抵抗及青春期2型糖尿病动物模型的特点

目的：分析高脂饮食诱导的青春期胰岛素抵抗大鼠及青春期2型糖尿病大鼠的特点。方法：通过正常血糖-高血浆胰岛素钳夹实验评估两种大鼠模型的胰岛素敏感性；对两种模型大鼠的雄激素与胰岛素敏感性的相关性进行研究，并与高脂饮食的成年期大鼠比较异同。结果：青春期胰岛素抵抗雄性大鼠的睾酮水平显著降低，且与胰岛素敏感性呈相关关系；小剂量链佐菌素（STZ）并不明显破坏胰岛细胞，但可使青春期胰岛素抵抗大鼠发生糖尿病（2型糖尿病）；青春期大鼠高脂饮食后仅仅甘油三酯（TG）和低密度脂蛋白胆固醇（LDL-C）升高，而成年胰岛素抵抗大鼠血脂代谢已经全面异常。结论：高脂饮食诱导的青春期大鼠胰岛素抵抗及2型糖尿病的发生可能与其血浆睾酮水平异常有关。     

Steroid hormone modulation of olfactory processing in the context of socio-sexual behaviors in rodents and humans

Primer pheromones and other chemosensory cues are important factors governing social interactions and reproductive physiology in many species of mammals. Responses to these chemosignals can vary substantially within and between individuals. This variability can stem, at least in part, from the modulating effects steroid and non-steroid hormones exert on olfactory processing. Such modulation frequently augments or facilitates the effects that prevailing social and environmental conditions have on the reproductive axis. The mechanisms underlying the hormonal regulation of responses to chemosensory cues are diverse. They are in part behavioral, achieved through the modulation of chemoinvestigative behaviors, and in part a product of the modulation of the intrinsic responsiveness of the main and accessory olfactory systems to conspecific, as well as other classes, of chemosignals. The behavioral and non-behavioral effects complement one another to ensure that mating and other reproductive processes are confined to reproductively favorable conditions.     

A 7-week follow-up study of the behaviour of testosterone and cortisol during the competition period in rowers

Summary Nine rowers (six men of the regional and three women of the national top class) participated in the study. During 7 consecutive weeks of the competition period serum testosterone (T), SHBG, cortisol (C) and urea were determined at the same time every morning under fasting conditions. From the concentrations of T and SHBG the free testosterone fraction (T/SHBG) was calculated, and from the concentrations of T and C the ratio of T/C was derived. The object of the investigation was to gather information on a potentially altered anabolic-catabolic hormone relationship dependent upon the intensity of the individual training periods. All rowers showed a continuous decrease in T, T/SHBG and T/C during the observation period. A week of regenerative training halted the decrease. In two of the oarsmen who discontinued their training after 2 and 3 weeks respectively, T, T/SHBG and T/C showed a normalization in the following weeks. In all subjects the concentrations of urea increased during the first 2 weeks and decreased during the subsequent weeks of intense training and competition. The findings suggest an increase in catabolic activity in periods of intensive physical strain, including competitions. Regenerative phases of training seem to reduce the anabolic-catabolic imbalance.Supported by Bundesinstitut für Sportwissenschaft, Köln, Federal Republic of Germany     

Splitting of wheelrunning rhythms by castrated or steroid treated male and female hamsters

Male and female hamsters, with or without gonadal hormones, were housed in constant light (LL) while wheel running rhythms were recorded. Estradiol benzoate (EB) in Silastic capsules reduced rhythm desynchronies, such as splitting, in ovariectomized animals compared to blank implanted controls. In males, there were no significant effects of testosterone or EB in Silastic implants, castration or sham operation on incidence of rhythm desynchronies. Males generated split rhythms which differed from females in clarity and the angle at which the limbs of the splitting rhythms diverged. Other differences were (a) greater activity onset variability for castrated females with relatively little onset variability for other groups and (b) more running time by EB treated males than any other group. Splitting for all animals occurred with an average latency in LL of 55±3 days; the period stabilized in 12±1 days and was 0.2 hr shorter in length. The two limbs of the split rhythm were a mean 181±5° apart. Induction of splitting by LL is critically discussed with special reference to the two oscillator model of hamster activity and existing evidence for more than two oscillations in wheelrunning activity.     

Intruder gonadectomy and elicitation of territorial aggression in the rat.

Long-Evans rats (male castrates, female castrates, and intact males) were compared for aggression eliciting qualities in a test of conspecific territorial aggression. Mature resident males, known to reliably attack male intruders, were presented with each type of intruder in a latin-square design with replications. Intact and castrate males were both attacked and sustained numerous wounds, whereas castrate females were subject to intensive social-investigatory behaviors but were not attacked. Intact males were severely attacked, with one-third killed by bite wounds. Castrate males were also attacked but sustained fewer wounds and no deaths. Apparently, castration decreases intensity of resident aggression but fails to block the discrimination of male characteristics eliciting attack.     

A Comparison of Endocrine Function and Semen Analysis in Fertile and Subfertile Men

We studied 121 normozoospermic, 62 oligozoospermic and 22 azoospermic patients and compared serum testosterone, LH and FSH with semen analysis. Testosterone was similar in all three groups studied. FSH rose significantly in the oligozoospermic and azoospermic groups (p < 0.01). LH was similar in the normozoospermic and oligozoospermic groups but rose significantly in the azoospermic group (p < 0,01). The rise in FSH is in accordance with the theory of inhibin release during the maturation states of spermatogenesis. The rise in LH might indicate a separate feedback mechanism mediated by the early stages of spermatogenesis and not by testosterone alone.
Ein Vergleich zwischen endokriner Funktion und Samen-Analyse bei fertilen und subfertilen Männern

Zusammenfassung

Wir untersuchten 121 Patienten mit Normozoospermie, 62 mit Oligozoospermie und 22 mit Azoospermie und verglichen das Serum-Testosteron, -LH und -FSH mit der Analyse des Samens. Das Testosteron war gleich in allen untersuchten Gruppen. Das FSH stieg signifikant an bei den Gruppen mit Oligozoospermie und Azoospermie (p < 0,01). Das LH war gleich bei den Gruppen mit Normozoospermie und Oligozoospermie, aber stieg signifikant an bei der Gruppe mit Azoospermie (p < 0,01). Der Anstieg des FSH stimmt überein mit der Theorie der Inhibinfreisetzung während der Reifestadien der Spermatogenese. Der Anstieg des LH könnte auf einen separaten Feedback-Mechanismus hinweisen, der durch die frühen Stadien der Spermatogenese und nicht durch Testosteron allein beeinflußt wird.     

The effects of testosterone and its metabolites on sexual behavior and morphology in male and female Japanese quail

Adult Japanese quail are sexually dimorphic. Even when implanted with testosterone (T), ovariectomized females fail to copulate and their cloacal glands are smaller than those of males. This may be due to a reduced capacity of the females to transform testosterone into active metabolites (estradiol-17β and 5α-dihydrotestosterone). Indeed, in the male quail, estradiol-17β (E₂) activates copulation whereas 5α-dihydrotestosterone (5α-DHT) activates crowing, strutting and the development of the cloacal gland. To test this hypothesis, we studied the effects of in vivo treatments of male and female quail with the different T-metabolites. Forty-one castrated male and female quail were implanted with subcutaneous silastic implants of T, 5α-DHT, E₂ and E₂ in combination with 5α-DHT. When implanted with these metabolites, females failed to copulate and their cloacal glands remained less developed than those of males. Sexual differences in behavior and morphology thus cannot be entirely explained by sexual dimorphism of the metabolism.