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Biomedical subjects

C J Wensing

Publications and source records attributed to C J Wensing.

At least 73 records · Page 4Linked to original sources

Induction of spermatogenesis in the naturally cryptorchid pig.

Abdominal testes of adult, naturally unilaterally cryptorchid boars were subjected to continuous artificial cooling for 5, 15, 25, or 45 days. This treatment initiated development of the spermatogenic epithelium. After a cooling period of 45 days there was complete differentiation in many seminiferous tubules. The results indicate that the spermatogenic arrest in abdominally located testes is not due to an inborn defect in the testis, but is caused by the maintenance of the testis at the abdominal temperature.

Animals↗

The origin of orchiopexy-induced testicular lesions in the pig.

Cooling experiments of abdominal testes in adult, naturally cryptorchid pigs indicate that spermatogenic arrest in abdominal testes is not due to an inborn defect, but is caused solely by maintenance of the testis at abdominal temperature. It is postulated that failure of spermatogenic cells to differentiate after orchiopexy results from surgical trauma. Evaluation of the orchiopexy procedure revealed that simple manipulation of a normally descended testis may give rise to damage to the spermatogenic epithelium. Furthermore, it appeared that, in normally descended testes of naturally unilaterally cryptorchid pigs subjected to orchiopexy, the spermatogenic epithelium was poorly developed as compared with that of scrotal testes of unilaterally cryptorchid pigs that had not undergone a surgical procedure.

Animals↗

Changes in serum testosterone concentrations in the male pig during development.

Serum testosterone concentrations were elevated between 40 and 60 days p.c. but were low between 60 and 100 days p.c. when the testis descends. Elevated concentrations occurred in the perinatal period and from the 18th week after birth. Between 60 days p.c. and 16 weeks after birth the changes in serum testosterone concentrations parallel those of testicular development, as determined by morphology and steroid histochemistry, and peripheral LH concentrations.

Animals↗

Gonadotrophic hormones and testicular descent.

The effect of fetal decapitation on gubernacular development and testicular descent was studied in the pig. Gubernacular development was unaffected and testicular descent occurred normally in decapitated fetuses. Neither testicular descent nor gubernacular development could be induced by HCG or LH-RH, administered to naturally unilateral cryptorchid prepuberal pigs in doses comparable to those used in human therapy. Gubernacular development and, subsequently, testicular descent seem to be independent of gonadotrophic stimulation.

Animals↗