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G. S. GUPTA and S. R. BAWA

The activity of seminal vesicle and prostate is known to be under the control of testosterone produced by the testis. Lindner & Mann (1960) described a significant correlation between the testosterone content of bull testes and the weight of seminal vesicles and their fructose and citric acid contents. In rats and rabbits, it was shown that the seminal fructose disappears after castration and the administration of testosterone leads to the reappearance of fructose in prostates and coagulating glands (Mann, 1964). Similiar correlations between the action of administered testosterone and the level of acid phosphatase and citric acid in semen have been observed by various workers (Mann, 1964). However, reports on the effects of X-irradiation on biosynthesis of androgens by testicular tissue in vivo and in vitro are not established; conflicting reports are found in literature
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G. S. GUPTA and S. R. BAWA

Our knowledge of the effects of ionizing radiation on the biochemical processes of testes and epididymides is meagre. Enzymatic studies of reproductive organs have been described (Ito, 1966; Gupta & Bawa, 1969), but the immediate effect of radiation in cell injury has been related to the curtailment of biosyntheses of nucleic acids and alterations in their chemical configuration. The events preceding the decrease of nucleic acid syntheses and other metabolic processes during irradiation are not understood. This communication describes the effects of localized γirradiation on phosphatases and their probable rôle in the regulatory mechanisms in the testes and epididymides.

Thirty, normal, white albino rats, weighing 140 to 200 g, were separated to form seven groups, consisting of four to five rats in each group. Rats were irradiated at a single surface dose of 2000

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G. S. GUPTA and S. R. BAWA

Department of Biophysics, Panjab University, Chandigarh, India

(Received 21st January 1974)

Glycogen has been demonstrated in non-germinal cells of the testes in many species (Free, 1970). In the rat, however, the Sertoli cells and the interstitial cells are characterized by the absence of glycogen (Nicander, 1957; Leiderman & Mancini, 1969). The germinal cells are the major sites for the deposition of glycogen and their content declines progressively from the immediate postnatal period to adult-hood (Leiderman & Mancini, 1969). As atrophic testes resulting from irradiation consist largely of non-germinal cells (Ellis, 1970), it is assumed that the changes in the glycogen levels in such testes mirror the events associated with the interstitial and Sertoli cells.

Normal adult rats (150 to 200 g) were allocated to fifteen groups, with three to five rats in each group. Anaesthetized rats, without shielding, were laid in a supine position on a dissecting board. The body

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G. S. GUPTA and S. R. BAWA

Summary.

The decrease in the uptake of 65Zn by irradiated testes (720 R) was followed by recovery after 30 days. After a dose of 2000 R, uptake of 65Zn was systematically reduced over a period of 74 days. Studies following the administration of testosterone and FSH to the irradiated rats confirm that the incorporation of zinc in the nongerminal cells of the testes is under the control of pituitary gonadotrophins.

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G. S. GUPTA and S. R. BAWA

Summary.

Acid phosphatase is present in the nucleus and cytoplasm of cells in the seminiferous tubules and the interstitium of rat testes. The effect of irradiation on acid phosphatase is dependent on the environmental temperature and the dose of irradiation. It appears that initial rise in the enzyme at a low radiation dose and a high environmental temperature or at a high dose and low temperature is associated with a lysosomal breakdown of the germinal cells of the testes. A decrease in acid phosphatase in the advanced stages of radiation injury is a secondary radiation effect which may lead to decreased metabolic synthesis of phosphate esters owing to the unavailability of orthophosphate in the testicular tubules. The reduced acid phosphatase activity can be detected in the seminiferous tubules, suggesting that the enzyme activity is related to the state of the germ cell population. An initial increase in acid phosphatase is matched by an initial rise in acid DNAse within hours of irradiation, further suggesting that there is radiation interaction with the cells of the germinal epithelium. The enhanced activity of DNAse following a 2nd week of irradiation at 2000 R confirms the phagocytic activity of the non-germinal cells.

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G. S. POPE, S. K. GUPTA and I. B. MUNRO

Summary.

The levels of progesterone in the systemic plasma of eight normal and two ovariectomized cows were estimated by gas chromatography. During the last month of pregnancy, levels varied mostly in the 2·5 to 7·5 ng/ml range (0·5 to 3·0 ng/ml at calving). For six of the eight cows, there was a significant fall in level during this period; pooling of the data for all eight showed a highly significant fall.

Levels near the time of ovulation, whether or not this was associated with behavioural oestrus, were below 2 ng/ml ; they rose and fell during ovulation cycles as corpora lutea grew and regressed. Mean peak level for twenty-two cycles was 9·0 ng/ml and occurred on average 13 days after ovulation. The time of most rapid fall in progesterone level was, on average, 4 days before ovulation.

Mean levels during the first 14 days after oestrus in normal cycles were not different from those during the first 14 days after insemination in early pregnancies; they then declined in the cycles but not during the early pregnancies.

Mean progesterone levels in the plasma of ovariectomized cows up to 200 days after the operation were below 2 ng/ml; levels showed a slow but significant rise during this period.

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M. R. Bansal, K. C. Kanwar and G. S. Gupta

Summary. Hyaluronidase from rhesus monkey testes was purified by detergent extraction, ammonium sulphate fractionation, Sephadex G-200 column chromatography and concanavalin A—Sepharose affinity chromatography. The purified hyaluronidase showed one protein band on acrylamide gel electrophoresis. Antibodies to the purified hyaluronidase were raised in rabbits and showed a single precipitin line by Ouchterlony gel diffusion. The enzyme had a molecular weight of 62 000. The K m was 0·5 mg/ml for hydrolysis of hyaluronic acid at 37°C. The optimum pH for the enzyme was 5·0 but activity was present over a broad pH range. The hyaluronidase was inhibited by HgCl2, CuSO4, FeSO4 and p-chloromercuribenzoate all at a concentration of 2 × 10−4 m. Cysteine protected the enzyme against HgCl2 inhibition.

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H. Bagavant, P. Thillai-Koothan, M. G. Sharma, G. P. Talwar and S. K. Gupta

Female bonnet monkeys Macaca radiata (n = 8, four per group) were immunized with purified 55 kDa glycoprotein from porcine zona pellucida (ZP3) and ZP3 conjugated to the β subunit of human chorionic gonadotrophin (βhCG) using adjuvants permissible for human use (alum, muramyl dipeptide and sodium phthalyl derivative of lipopolysaccharide). The animals were monitored for anti-ZP3 antibody titres, biweekly progesterone concentrations, menstrual cyclicity and status of fertility. All the animals generated a good anti-ZP3 antibody response, continued to have ovulatory cycles, remained infertile in the presence of high anti-ZP3 antibody titres and showed no disturbance in cyclicity (except summer amenorrhoea). Examinations by laparoscope showed normal ovaries with developing follicles or corpora lutea on the surface. Fifty per cent of the animals conceived after a decline in antibody titres. Ovaries of animals that failed to regain fertility were examined for changes in morphology at times when anti-ZP3 antibody titres in the circulation were low and following a booster when titres were high. None of the ovaries showed any sign of inflammation or lymphocytic infiltration. Follicles at different stages of development were seen in all of the ovaries. No significant reduction in the number of follicles, except in one monkey (MRA 178), was observed. There was no increase in the numbers of atretic or degenerating follicles. The results showed that ZP3 immunization with permissible adjuvants could be used for immunocontraception without obvious ovarian changes.

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Jayasree SenGupta, P. D. Gupta, S. K. Manchanda and G. P. Talwar

Summary. By using an immunoperoxidase indirect antibody method, mouse blastocysts were found to bind specifically hCG and ovine LH but not FSH or the β unit of hCG. Brown peroxidase reaction products were present in the morula and increased with the formation of the blastocoele. The LH/hCG binding 'sites' may be related to the initiation of steroidogenesis in the embryo.

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S. Paul, P. D. Gupta, B. L. Jailkhani and G. P. Talwar

Summary. Human placental syncytiotrophoblast was not lysed when exposed to acutely hypotonic environments (distilled water) or during repeated freeze—thawing. The ability of the syncytiotrophoblast to synthesize and secrete hCG was not blocked after exposure to hypotonic stress (0·055 osmol) and elevated temperature (47°C), treatments which caused lysis of erythrocytes and lymphocytes. The stressresistant property of the syncytiotrophoblast may be an important element in enabling its survival as a barrier between the maternal environment and the conceptus.