Seasonal variation of LH and testosterone in the smallest deer,the pudu (Pudu puda molina) and its relationship to the antler cycle

• 1.1. In order to obtain a seasonal profile of LH, three adult male pudu (Pudu puda, Molina) were sampled monthly from the saphenous vein for a period of one year.
• 2.2. A significant circannual variation of plasma LH levels was detected with an average peak value (1.77 ng/ml) recorded in February and nadir concentrations (0.19 ng/ml) observed in November.
• 3.3. The peak level of testosterone (1.54 ng/ml) was detected in March, the time of the rut.

     

The effect of cyproterone acetate on the antler cycle in red deer (Cervus elaphus L.)

The aim of the study was to test the effect of antiandrogen, cyproterone acetate (CA) on the antler cycle in the red deer (Cervus elaphus). CA was administered to three adult red deer stags (Edward, Fuks and Gacek) in weekly intervals. Edward and Fuks were given 600 mg + 600 mg of CA, whereas Gacek was given 600 mg + 300 mg. CA was injected during the hard antler phase: in mid-October (Edward), at the end of November (Fuks) and at the end of January (Gacek). CA caused the antler casting 17 to 22 days after the first injection. In all stags, the casting of antlers was followed by a period of intensive growth of new antlers. Edward was given CA at the end of October. This treatment was responsible for occurrence of the two antler cycles in the year of the experiment. When CA was administered during the middle of the hard antler phase an additional short antler cycle occurs followed by new antler growth. CA treatment in the later part of hard antler phase may cause a prolonged antler cycle.     

Effect of antiandrogen cyproterone acetate on the action of testosterone on mouse kidney.

The loss of endogenous testosterone in castrated male mice leads to a marked decrease in seminal vesicle and kidney tissue weight. 21 days' administration of exogenous testosterone abolished the effect of castration on the seminal vesicles and kidney tissue. The antiandrogen cyproterone acetate produced significant changes in the target tissue for androgens, i.e. in the seminal vesicles. In every case it blocked the action of both exogenous and endogenous testosterone on the seminal vesicles, but failed to block the "renotropic" action of testosterone, expressed as relative kidney weight. Contrary to its effect on the seminal vesicles, it did not influence relative kidney weight in normal animals. It likewise did not block the effect of exogenous testosterone on kidney tissue. The mechanism of the action of cyproterone acetate in androgen-dependent tissues is known to consist in inhibition of androgen binding to specific cell receptors in the target tissues. Some of the specific androgen receptors in mouse kidney are evidently different in character from those in the accessary sex glands, that being the reason why cyproterone acetate has an antiandrogenic, but not an antirenotropic effect. In agreement with experiments on rats, adrenal weight also decreases in mice after the administration of cyproterone acetate.     

On the banding patterns of the chromosomes of the Pudu pudu (PUDU)

The cytogenetic study of the Pudu Pudu (Pudu) shows a diploid number of 70 chromosomes (2n = 70). We present here for the first time data on their banding pattern which reveal peculiars C-bands and allow precise identification of the chromosomal set. Homozygous expression of an autosomal fragile sites was found in the largest acrocentric pair.     

Macroscopic description of the bones of the forelimb of Pudu pudu (Molina 1782)

The present study describes the anatomical details of the bones of the thoracic limb from Pudu pudu (Molina 1782). The results were similar to findings discovered in Capreolus capreolus, Dama dama, and Ovis aries, while there were hardly any similarities to findings in Capra hircus.     

Macroscopic presentation of the bones of the pelvic limb of Pudu pudu (Molina 1782)

The present study describes the anatomical details of the bones of the pelvic limb from Pudu pudu (Molina 1782). The results were similar to findings in Dama dama and Ovis aries, while there were very few similarities to findings in Capra hircus.     

Effects of the antiandrogen cyproterone acetate on reproduction in male and female ring doves

The present experiment was designed to study the role of increased plasma androgens which are seen in male and female doves during courtship. In pairs of doves either the male or female was injected daily with oil or with 6 or 15 mg of cyproterone acetate (CA), starting 3 days before pairing. Cyproterone acetate at both dose levels reduced the amount of bow-cooing shown by the male on the day of pairing, and at the higher dose resulted in a reduction of nest soliciting by injected males and their untreated mates over the 7 days of testing. At the high dose only, the size of the testes was reduced. In pairs where females received CA, there was a decrease in levels of nest soliciting by both partners and ovarian development was blocked. The results are discussed in terms of the possible significance of fluctuating androgen levels found in doves during the prelaying period.     

Effects of an antiandrogen,cyproterone acetate,on the kidney of the three-spined stickleback (Gasterosteus aculeatus L.)

The fine structure of the kidney is studied in the sexually mature male three-spined stickleback after administration of an antiandrogen, cyproterone acetate. Under these conditions, the dedifferentiation of renal tubules is characterized by the same involutive processes as those induced by castration, with the difference that cyproterone acetate only begins to act after 14 days whereas after castration the first signs of involution are visible after 7 days. The ultrastructural modifications affect the nucleoli, the rough endoplasmic reticulum and the Golgi apparatus. They reflect an inhibition of the secretory process. The results obtained demonstrate that administration of cyproterone acetate to male sticklebacks has an inhibitory effect on renal target cells, apparently indistinguishable from the changes induced by lack of male sex hormone, and that this drug may be a valid substitute for castration in fish.