In male rats, experimentally induced diabetes mellitus has been reported to be associated with reduced serum levels of gonadotropins and testosterone as well as decreased sex accessory organ weights. The purpose of the present study was to determine if the decreased accessory organ weights and gonadotropin levels observed in diabetic animals result from alterations in the ability of target tissues to respond to testosterone. Adult, male, Wistar rats were injected with streptozotocin (STZ) and either maintained as untreated diabetics or treated with daily injections of insulin. Semi-starved animals were included to control for any effects on the reproductive system due to body weight change alone. These three groups, plus intact controls, were maintained for 30 days with one-half of the animals from each group receiving silastic tubing implants of testosterone of various lengths. It was determined that, in uncontrolled diabetic and semi-starved animals, the serum levels of LH, FSH, and testosterone were decreased, as were the weights of seminal vesicles and ventral prostate glands. Insulin treatment restored LH, FSH, and testosterone levels to normal. Sex accessory glands exhibited slight, but significant, recovery in diabetic animals treated with insulin. Implants of testosterone that resulted in physiologic serum levels of testosterone were effective in depressing serum LH and FSH levels as well as in maintaining normal seminal vesicle and ventral prostate weights in control and semi-starved animals.(ABSTRACT TRUNCATED AT 250 WORDS)

The adult male golden hamster will undergo testicular regression when exposed to a short photoperiod, blinding, or late afternoon injections of melatonin. The present study was conducted to compare the effects of all three treatments on serum gonadotropin levels and testicular weights, and to evaluate the effects of these treatments on hypothalamic content of both immunoreactive and bioactive luteinizing hormone-releasing hormone (LHRH) levels. Hamsters were blinded (BL), exposed to a short photoperiod (SP), or received daily injections of melatonin (MEL) for 15 wk. Each treatment (BL, SP, MEL) induced a temporally similar decline in serum luteinizing hormone (LH), serum follicle-stimulating hormone (FSH), and testicular weight. Spontaneous recrudescence occurred earliest in the MEL group, with serum gonadotropins and testicular weight returning to normal by 15 wk. The SP group exhibited recovery of serum gonadotropins but not testicular weight by 15 wk. The BL group demonstrated partial recovery of serum FSH levels by 15 wk, with no recovery in either serum LH or testicular weight. Each treatment group demonstrated increased hypothalamic content of immunoreactive LHRH which was temporally correlated with the decreases of serum gonadotropins. Additionally, the MEL and SP groups demonstrated decreased immunoreactive LHRH levels during spontaneous recrudescence. Extracts of hypothalami from all treatment groups were bioactive on control hamster pituitary cells. These results indicate that there are temporal differences among the three common treatments and that these differences are manifested in serum gonadotropins, testicular weight and hypothalamic LHRH. Hypothalamic LHRH levels determined by radioimmunoassay and bioassay show periods of increase and decrease which coincide with periods of altered serum gonadotropin levels in all groups.

The intraluminal injection of oil produced deciduoma formation in ovariectomized, mast cell-normal (+ /+) and mast cell-deficient (W/Wv) mice that were treated with exogenous steroids. Oil injection and trauma (e.g. sutures) also produced a deciduoma in ovariectomized + / + and W/Wv mice that had received a single control (+ / +) ovary transplanted under the kidney capsule. After transfers of donor blastocysts, implantation and live births were obtained in +/+ and W/Wv mice containing a single ovary transplant. Our results demonstate that uterine mast cells are not required for the production of a decidual cell response, implantation, gestation or the birth of live offspring in mice.

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Testicular regression was induced in adult hamsters by optic enucleation, short photoperiod, or melatonin injections. The melatonin injected group, while undergoing testicular regression, showed a quite different time course from the optic enucleated and short photoperiod groups. All three methods resulted in the restoration of Sertoli cell responsiveness to FSH in vitro from the adult level to that of Sertoli cells from immature hamsters 18-20 days of age. the melatonin injected group showed a shift in testis weight which resulted in a half maximal restoration of Sertoli cell responsiveness to FSH compared to the other groups. This restoration of Sertoli cell responsiveness to FSH was blocked by pinealectomy. These data indicate that the pineal has a specific (but not necessarily direct) effect on Sertoli cell function. In addition, the effect of melatonin injections is qualitatively but not quantitatively similar to optic enucleation and short photoperiod both with regard to testicular regression and alteration of Sertoli cell response.

Rabbit sperm motility was measured spectrophotometrically and a sperm motility index (SMI) was obtained. A comparative analysis between the SMI values and the velocity of motile sperm (obtained by time lapse photography of sperm tracks) was performed. The SMI specifically was compared to the mean velocity of the first 300 sperm cells observed and to the mean velocity of just the first 300 progressively motile sperm cells. In both comparisons, the SMI was highly correlated to the sperm track length (sperm velocity). In addition, a modification of the spectrophotometric procedure is described which allows measurements of the SMI to be made on semen extended into egg-yolk glycerine cryopreservation agents.

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