Changes in spermatogenesis and endocrine function in the ram testis due to irradiation and active immunization against luteinizing hormone-releasing hormone1,2

Abstract

Spermatogonial stem cell transplantation is a technique that has potential in livestock to enhance genetic gain and generate transgenic offspring through the male germ line. A means for depletion of endogenous germ cells in a recipient's seminiferous tubules is necessary for this technology to be applied. The objectives of this study were to evaluate several methods for depletion of endogenous germ cells in the testes of adult rams and to evaluate ultrasound-guided injections into the rete testes as a means for infusing a suspension into the seminiferous tubules. Sixteen adult rams were randomly divided into 4 treatment groups (n = 4 per group). Treatments consisted of active immunization against LHRH (IMM), localized testicular irradiation (IR), LHRH immunization + irradiation (IMM+IR), and untreated control. Serial bleedings were conducted pretreatment and monthly after treatment for 4 mo, at which time all rams were castrated. Both IMM and IMM+IR rams received exogenous gonadotropin in the form of Perganol weekly for 8 wk before castration to bypass the immunization. All rams also received an ultrasound-guided injection of PBS containing 0.4% trypan blue into the rete testis of one testicle before castration. Rams receiving IMM and IMM+IR treatments had higher (P< 0.05) average percentages of seminiferous tubule cross sections with depleted germ cells compared with controls. Serum testosterone was decreased (P < 0.05) in IMM and IMM+IR rams 1 mo after treatment and throughout the remainder of the study compared with controls and IR rams, which were not different from each other. Serum inhibin concentration was unchanged in all rams following treatment indicating that Sertoli cell function was unaltered. A greater (P < 0.05) average percentage of the total testicular area could be filled with the trypan blue solution by rete testis injection in IMM and IMM+IR rams. These data demonstrate the depletion of endogenous germ cells in adult ram testes without alteration of Sertoli cell viability and function that have potential as methods for preparing recipient animals for germ cell transplantation.

Effect of curcumin on dexamethasone-induced testicular toxicity in mice

“…Average percentages were calculated for each sample by dividing the number of round tubules with a histopathologic index (vacuolization, detachment, sloughing) or normal tubules in a randomly microscopic field by the total number of round tubules in the same field and the result multiplied by 100. For each slide the mean of three fields was considered (D'Cruz & Uckun, 2000;Oatley et al, 2005).…”

Irradiation Enhances the Efficiency of Testicular Germ Cell Transplantation in Sheep

“…In rodents, depletion of endogenous testicular stem cells by irradiation or chemotherapy drugs is a prerequisite for successful transplantation. Until now, there has been little information in the literature with regard to the beneficial effects of the preparation of recipients in germ cell transplantation among livestock animals [18,19]. In the present study, we developed an effective protocol for testis germ cell transplantation in sheep and then compared the effect of different doses of irradiation on the outcome of germ cell transplantation.…”

Toxic effects of Carthamus tinctorius L. (Safflower) extract on mouse spermatogenesis

“…Average percentages were calculated for each sample by dividing the number of round tubules with a histopathologic index (vacuolization, detachment, sloughing) or normal tubules in a randomly microscopic field by the total number of round tubules in the same field and the result multiplied by 100. For each slide the mean of 3 fields was considered [13].…”