Inhibition of 3 beta-hydroxy-delta 5-steroid dehydrogenase in rat testicular tissue by mercuric chloride

Histochemical investigations of 3 beta-hydroxy-delta 5-steroid dehydrogenase (delta 5-3 beta OHD) activity in the testicular tissue of rats administered mercuric chloride (HgCl2) at dosages of 0.05 mg/kg and 0.1 mg/kg (i.p.) daily for 90 days reveal a graded inhibition of delta 5-3 beta OHD activity which was positively related to dosage and to the duration of treatment with this compound. This phenomenon may be mainly responsible for the inhibition of spermatogenesis, observed as a toxic manifestation of mercury compounds.

Thyroid-testis interrelationship during the development and sexual maturity of the rat

The effects of thyroidectomy and treatment with thyroxine (T4) were studied in immature male rats to evaluate the role of the thyroid in the development of testicular functions. Thyroidectomy inhibited gametogenesis and development of the Leydig cell in these rats. However, the effects could be reversed by administration of 10 micrograms T4 (i.p.) daily for 30 days.

Role of thyroid in testicular development of immature rat

Prepubertal spermatogenic cells in immature rats show pronounced dependency on thyroid hormone. In thyroidectomized immature male rats widespread regression of these cells were observed. These changes could be prevented by administration of small doses of thyroxine. In unthyroidectomized immature rats, thyroxine in the same dosage, caused an increased degree of growth and development of testicular tissues as compared to control.

Zinc content in the epididymis, vas deferens, prostate, and seminal vesicles of juvenile rhesus monkey (Macaca mulatta): effect of androgen and estrogen

The zinc content in the three segments of the epididymis (caput, corpus, and cauda), vas deferens, seminal vesicles, and prostate of juvenile monkeys was determined by atomic absorption spectrophotometry. Zinc content (micrograms/gm wet weight) was found to be maximum (328) in the vas deferens; in the other organs it measured in the following order: caput 191, corpus 238, cauda 193, prostate 133 and seminal vesicles 85. In order to investigate the endocrine control of the zinc in these organs, two groups of animals were treated with testosterone propionate (2 mg) or estradiol dipropionate (10 micrograms) once daily for 30 days. In response to androgen, a rise in both concentration and content of zinc was evident only in the prostate. The results further suggested that the prostatic zinc may be under dual hormonal control, but in the epididymis and vas deferens it may be under the influence of estrogen. It is concluded that the hormonal effects on zinc content and growth stimulation in accessory sex organs are quite separate and may be under different hormonal control.

Interaction of dexamethasone and dehydroepiandrosterone on testicular ascorbic acid and cholesterol in prepubertal rat

A sharp decline of cholesterol and ascorbic acid in the immature testicular tissues was observed after treatment with two dosages of dexamethasone (DXM) i.e., 20 and 40 micrograms i.p. for 10 days daily to 10-day old rats weighing around 40gms. Reversal of these effec s was noted with the concurrent administration of 80 micrograms dehydroepiandrosterone (DEAT) along with both doses of DXM over a similar period. However, 20 micrograms of DEAT was found to be ineffective when administered concurrently with DXM in either of the dosage levels demonstrate the functional roles of ascorbic acid and cholesterol in the prepubertal rat testis.

Effect of selenium dioxide on the testes of rat

Selenium dioxide was administered (ip) to albino male rats (200 +/- 5 g) in increasing doses (2, 6 and 10 micrograms/rat, daily) for 90 days. Histologic and histometric study showed that there was dose dependent injury to testes. No cellular deformation was observed following 2 micrograms-dose; whereas 6 micrograms-dose caused significant damage of gametogenic cells. At a dose of 10 micrograms, there was a significant testicular degeneration along with testicular atrophy.

Production of Diosgenin in somatic callus tissues of Dioscorea floribunda

Shoot-tip and tuber-derived callus tissues of Dioscorea floribunda Mart, and Gal. when grown in revised tobacco medium supplemented with 1 and 2 mg/12,4-D, contained 0.295% and 1.33% diosgenin, respectively.

Zinc content of maturing spermatozoa in oestrogen treated rats

Zinc content of spermatozoa collected from the caput and cauda portions of the rat epididymis was determined by atomic absorption spectroscopy. The results showed about 60% reduction in the spermatozoal zinc content by the time they reach the cauda epididymis. This reduction was inhibited in rats receiving micro dose oestrogen which induced 'functional' sterility. It appears that the fall in zinc content of spermatozoa during their transport in the epididymis is related to sperm maturation and that oestrogen treatment interferes with this reduction in sperm zinc content.

Toxic effect of mercury on testes in different animal species

Testicular changes following the administration of mercuric chloride, (HgCl2, ip in various dosages) over one month were studied in rats, mice, guinea pigs and hamsters. HgCl2 (5 mg/kg) caused a testicular degeneration and cellular deformation was observed in both the seminiferous tubules and the Leydig cells in all species: a significant decrease of testicular weight also resulted. There was no cellular deformation at the dose of 2 mg/kg: only spermatogenic inhibition and Leydig cell atrophy were observed in the animals. At the dose of 1 mg/kg, testicular degeneration was observed only in the hamster, only partial degeneration was recorded in the rat and the mouse and no change was noted in the guinea pig.

Zinc in the epididymal and vasal spermatozoa of rhesus monkey (Macaca mulatta)

Zinc level in maturing spermatozoa collected from caput, corpus, and cauda regions of the epididymis and vas deferens of rhesus monkey was measured. Spermatozoa collected from the caput epididymis have the highest concentration of zinc (36 micrograms/10(8) spermatozoa). There was a marked reduction in the zinc content of corpus spermatozoa and a further decrease in the spermatozoa of cauda epididymis. Thus the zinc content of spermatozoa gradually decreases as they migrate from the caput to cauda epididymis. There was a significant increase in the zinc content of vasal spermatozoa as compared to those collected from the cauda region of epididymis.

Role of ACTH on the cytomorphology of testes of the immature rat

The male gametogenic development of the immature rat shows inhibitory effect by the exogenous infusion of ACTH (0.25 IU and 0.50 IU; i.p.). Seminiferous tubular degeneration, Leydig cell atrophy and Sertoli cell regression are very conspicuous in the dosage of 0.50 IU ACTH (i.p.). Cytometrical and histological evidence confirms that ACTH could be inhibited by FSH during male gametogenic development which leads to cellular degeneration of testes in the immature rat.

Histological changes in thyroid of rat under the acute exposure of O-chloro-benzylidine malononitrile

This communication describes histological changes in the thyroid gland of rats under the acute stress of O-chlorobenzylidene malononitrile (CS) 10 mg/kg and 20 mg/kg). It has been observed that CS, when injected, causes histological changes in the thyroid of varying degrees, depending on the dose used.

Cellular changes of adrenal under the acute stress of O-chlorobenzylidene malononitrile (CS)

This investigation describes histological and cytometrical changes of cortical and medullary tissue of adrenal in rats under the acute stress of O-chlorobenzylidene malononitrile (10 mg/kg and 20 mg/kg). It has been observed that after injection of CS, the adrenal gland showed histological changes both in the cortical and medullary region.

Zinc and copper content in rat epididymis and vas deferens

The zinc and copper content in the different epididymal segments and vas deferens of castrated rats were investigated with the help of atomic absorption spectrophotometer. The vas deferens showed maximum zinc content as compared to that of different parts of epididymis in all groups whether castrated unilaterally, bilaterally or in the intact control. Zinc content was reduced in the epididymis and vas deferens ipsilateral to the castrated side as compared to that of contralateral control and intake animals. Lowest zinc content was observed in the epididymis and vas deferens of bilaterally castrated animals from that of other groups. Absence of sperms was observed in all segments of epididymis and vas in bilaterally castrated animals and from the unilaterally castrated side. Copper content was unaltered in all epididymal segments and vas deferens. There appears to be a correlation between the absence of sperms in the male genital tract and the decrease in zinc content.

Release of copper ions from an intra-vas cooper-wire contraceptive device

Insertion of a copper wire into the vas deferens of male rats released 4 micrograms of copper in themid portion of the vas deferens in two days time. In urethral and epidymal segments of the vas deferens copper released was less than one microgram. The present study demonstrates that the in vivo effects of 4 microgram of copper in 2 days time in the vas deferens are enough to induce antifertility in rats.

Effects of glucagon and secretin on food- or morphine-induced motor activity of the distal colon, rectum, and anal sphincter

The effects of glucagon and secretin on food- or morphine-induced motor activity of the distal colon, rectum, and internal anal sphincter were investigated in 12 healthy subjects. Intraluminal pressure changes were measured using a triple-lumen polyvinyl tube assembly with 3 side orifices. Glucagon, administered intravenously, caused significant inhibition of food- or morphine-induced motor activity of both the distal colon and rectum. In contrast, secretin did not suppress morphine-induced motor activity but did significantly inhibit food-stimulated motor activity of the distal colon. The inhibitory effect of secretin on motor activity of the rectum was insignificant. Morphine, but not food, elevated the pressure of the anal sphincter which was not effected by glucagon or secretin. Hyperglycemia, produced by the infusion of 5% glucose, had no effect on motor activity. These studies demonstrate that glucagon but not secretin, in the doses employed, inhibits morphine-induced motor wave activity of both the distal colon and rectum and that this inhibitory effect is not secondary to hyperglycemia. Furthermore, the rise in anal sphincter pressure is not affected by glucagon or secretin.

Hemangioendotheliomatosis of the liver. A 12-year follow-up

Hemangioendothelioma of the liver is a rare tumor. A case is reported of a middle-aged woman who presented with hepatomegaly and ascites, and who has been followed for over 12 years. The clinical features, pathological, radiographic, portal hemodynamic, and metabolic changes are presented.