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10D 1. Steroids and the male reproductive system—I 355. Interaction of hormonal steroids with human spermatozoa
Abstracts
380
miniature pig plasma LH levels are not different from adults and plasma testosterone (T) is higher than in castrates. This initiated a study of (3) prepuberal steroid feed back and (b) dependance of prepuberal T-secretion on gonadotropins. Blood was taken by venipuncture before and at regular time intervals up to 4 weeks after surgery or treatment. (al 16 newborn males were either orchidectomized (0), hemiorchidectomized (HO) sham operated (SH) or served as controls (C). Plasma LH (RIA) in 0 and HO was not different from SH or C though plasma T (RIA) decreased to about 30”” and 60”,, respectively within one day and remained unchanged thereafter. Four weeks after HO no compensatory hypertrophy of the testes was observed. (b) 10 new-born animals were treated on day 1. 2. 5. 8, 12 of the experiment with 1000 IU HCG on each day i.m. or served as controls (C). After no initial response a dramatic increase of plasma T occurred on day 9 of the experiment. At 3 and 4 weeks after the first HCG administration, T levels equalled those of castrates. These data show (a) prepuberal steroid feed back in the male miniature pig is different from other species since a decrease of plasma T does not result in an increase of LH. (b) the already elevated plasma T in the prepuberal animal can be further increased only after prolonged and massive treatment with gonadotropins. A later decrease of T to castrate levels may be due to immunization against HCG-LH. (Supported by DFG).
352. Fully restored, maintained fertility of hypophysectomized (HE) male rats receiving long term testosterone propionate (TP) replacement therapy VONBERSWORDT-WALLRABE, R. and MEIIRING, M.. Schering A.G.. West-Berlin In order to reinitiate and preserve fertility in the absence of hypophyseal secretions, mature male rats of proven fertility were hypophysectomized and injected with TP. Twenty intact animals served 3s untreated controls. After surgery, rats received: 0.3. 05 and 50 mg TPiday s.c.. respectively, up to 245 days; another group: S,Omg TP/day s.c., commencing after an appropriate post-hypophysectomy regression period from day 22 after HE until day 252. All males were tested for fertility twice a week. Only the 5.0 mg TP/day maintained fertility continuously. When no TP was given during three weeks following HE, the testes were completely atrophic after this period of time. Nevertheless, 7 weeks after the onset of S-O mg TP/day, fertility was restored. Histology showed fully intact spermatogenesis in all groups; the Leydig cells seemed slightly atrophic. The epitheliunl of the dorsolateral prostate of substituted animals looked h~erplastic~adenomatoid. Hence, exogenous TP alone restored and maintained spermatogenesis and the fertility of hypophysectomized rats, even after complete regression of spermatogenic events. 353. Testicular response to i.v. luteiuizing hormone-releasing hormone (LH-RH) in normal men. Patterns of testosterone secretion throughout the day SCHWARZSTEIN, L., LABORDE, NILSA P. DE., APARICIO, N. J., R~~RUJEZ. A. and ROSNER, J. M., ILAFIR, Universidad de1 Salvador. San Miguel, P.B.A., Argentina In order LH-RH. different
to investigate five volunteer times: 06.00;
the testicular response to synthetic normal men were studied. At four 12.00: 18.00 and 00.00 h, synthetic
LH-RH (SO pg) dissolved in saline solution was injected into a cubital vein. Blood samples were drawn at 5 min prior to LH-RH administration and at 0, 8, 16,32, 64 and I38 min later. Plasma testosterone levels were determined by a double antibody radioimmunoassay method. Testosterone secretion showed a clear cut response to LH-RH in all the subjects studied. In three of the four timetables (0600. 18.00 and 00.00 h) testosterone values increased from 8 min reaching a maximum at 16 min and persisted at this level I28 nun later. The midday response (12.00 h) showed a gradual increase in the testosterone levels reaching a maximum at the end of the test period. These resul ts show 3 clear response of plasma testosterone to synthetic LH-RH. 354. Hormonal responses to the oral glucose tolerance test TRESGUERRES.J. A. F., RO~)RIGUEZ. F. J., MANCHFY?O, E., ORIOL-BOSCH, A., Department of Experimental Endocrinology, University CompIutensis Medical School, Madrid. Spain A standard (4Ogirn~) oral glucose tolerance test (OGTT) was performed at 16.00 h in IO males aged between 24 and 39 years, Blood samples were obtained at - 15, 0. 30, 60. 90 and 120 min after glucose intake. Measurements were made as follows: Blood glucose enzymatically. 1l-hydroxycorticosteroids (11-OHCS) fluorimetrically and insulin, LH, testosterone and renin activity (PRA) by RIA. The basal values and the glucose and insulin responses to the OGTT fell within the normal ranges. No significant variations of LH and II-OHCS were detected during the OGTT, but significant variations occurred in testosterone and PRA. OGTT decreased testosterone with minimum levels of 77 + 4O:, (X 2 sem) of the basai values at 90 min. PRA was increased with a maximum of 218 _t Xi”;, of basal levels at 6Om~n. Testosterone decrease could be due to either diminished sensitivity of the testis to plasma LH or increased metabolic rates, while PRA could by modified by changes in the glomerular filtration rate due to the hyperglycemia.
IOD 1. Steroids and the male reproductive system-1 355. lnteractionofhormonalsteroidswithhumanspermatozoa MERCADO, E., REYFS, A. and ROSADO. A., Section Bioquimica de la Reproduction, Departamento de Investigation Cientifica, C.M.N.. lnstituto Mexican0 de1 Social, Apdo. Postal 66-737. Mexico 12, D.F. Diluted suspensions of human sperm ceils when excited with monochromatic light at 288nm emitted a char~~cteristic fluorescence spectrum. This spectrum is quenched when steroid hormones are added to the medium. This quenching effect is evidence that sperm-steroid interaction has occurred. The three steroids studied interact with intact washed human spermatozoa, but testosterone is bound significantly less than oestrone or progesterone (2.5 against 4.5 and 5.0 nmol/ lOh cells respectively). However, the modification of the fluorescence is proportionately greater with testosterone than with the other two steroids, thus indicating a more significant interaction of the androgen with the sperm cells. The association constant of the sperm cell-testosterone complex is also significantly lower (2.76 x 10 -AM) than that ofoestrone(3.96 x 10‘JM)orprogesterone (h-46 x 10 ‘M). Binding of testosterone is then a more reversible process, indicative of a greater responsiveness to environmental changes in hormone concentration.
380
miniature pig plasma LH levels are not different from adults and plasma testosterone (T) is higher than in castrates. This initiated a study of (3) prepuberal steroid feed back and (b) dependance of prepuberal T-secretion on gonadotropins. Blood was taken by venipuncture before and at regular time intervals up to 4 weeks after surgery or treatment. (al 16 newborn males were either orchidectomized (0), hemiorchidectomized (HO) sham operated (SH) or served as controls (C). Plasma LH (RIA) in 0 and HO was not different from SH or C though plasma T (RIA) decreased to about 30”” and 60”,, respectively within one day and remained unchanged thereafter. Four weeks after HO no compensatory hypertrophy of the testes was observed. (b) 10 new-born animals were treated on day 1. 2. 5. 8, 12 of the experiment with 1000 IU HCG on each day i.m. or served as controls (C). After no initial response a dramatic increase of plasma T occurred on day 9 of the experiment. At 3 and 4 weeks after the first HCG administration, T levels equalled those of castrates. These data show (a) prepuberal steroid feed back in the male miniature pig is different from other species since a decrease of plasma T does not result in an increase of LH. (b) the already elevated plasma T in the prepuberal animal can be further increased only after prolonged and massive treatment with gonadotropins. A later decrease of T to castrate levels may be due to immunization against HCG-LH. (Supported by DFG).
352. Fully restored, maintained fertility of hypophysectomized (HE) male rats receiving long term testosterone propionate (TP) replacement therapy VONBERSWORDT-WALLRABE, R. and MEIIRING, M.. Schering A.G.. West-Berlin In order to reinitiate and preserve fertility in the absence of hypophyseal secretions, mature male rats of proven fertility were hypophysectomized and injected with TP. Twenty intact animals served 3s untreated controls. After surgery, rats received: 0.3. 05 and 50 mg TPiday s.c.. respectively, up to 245 days; another group: S,Omg TP/day s.c., commencing after an appropriate post-hypophysectomy regression period from day 22 after HE until day 252. All males were tested for fertility twice a week. Only the 5.0 mg TP/day maintained fertility continuously. When no TP was given during three weeks following HE, the testes were completely atrophic after this period of time. Nevertheless, 7 weeks after the onset of S-O mg TP/day, fertility was restored. Histology showed fully intact spermatogenesis in all groups; the Leydig cells seemed slightly atrophic. The epitheliunl of the dorsolateral prostate of substituted animals looked h~erplastic~adenomatoid. Hence, exogenous TP alone restored and maintained spermatogenesis and the fertility of hypophysectomized rats, even after complete regression of spermatogenic events. 353. Testicular response to i.v. luteiuizing hormone-releasing hormone (LH-RH) in normal men. Patterns of testosterone secretion throughout the day SCHWARZSTEIN, L., LABORDE, NILSA P. DE., APARICIO, N. J., R~~RUJEZ. A. and ROSNER, J. M., ILAFIR, Universidad de1 Salvador. San Miguel, P.B.A., Argentina In order LH-RH. different
to investigate five volunteer times: 06.00;
the testicular response to synthetic normal men were studied. At four 12.00: 18.00 and 00.00 h, synthetic
LH-RH (SO pg) dissolved in saline solution was injected into a cubital vein. Blood samples were drawn at 5 min prior to LH-RH administration and at 0, 8, 16,32, 64 and I38 min later. Plasma testosterone levels were determined by a double antibody radioimmunoassay method. Testosterone secretion showed a clear cut response to LH-RH in all the subjects studied. In three of the four timetables (0600. 18.00 and 00.00 h) testosterone values increased from 8 min reaching a maximum at 16 min and persisted at this level I28 nun later. The midday response (12.00 h) showed a gradual increase in the testosterone levels reaching a maximum at the end of the test period. These resul ts show 3 clear response of plasma testosterone to synthetic LH-RH. 354. Hormonal responses to the oral glucose tolerance test TRESGUERRES.J. A. F., RO~)RIGUEZ. F. J., MANCHFY?O, E., ORIOL-BOSCH, A., Department of Experimental Endocrinology, University CompIutensis Medical School, Madrid. Spain A standard (4Ogirn~) oral glucose tolerance test (OGTT) was performed at 16.00 h in IO males aged between 24 and 39 years, Blood samples were obtained at - 15, 0. 30, 60. 90 and 120 min after glucose intake. Measurements were made as follows: Blood glucose enzymatically. 1l-hydroxycorticosteroids (11-OHCS) fluorimetrically and insulin, LH, testosterone and renin activity (PRA) by RIA. The basal values and the glucose and insulin responses to the OGTT fell within the normal ranges. No significant variations of LH and II-OHCS were detected during the OGTT, but significant variations occurred in testosterone and PRA. OGTT decreased testosterone with minimum levels of 77 + 4O:, (X 2 sem) of the basai values at 90 min. PRA was increased with a maximum of 218 _t Xi”;, of basal levels at 6Om~n. Testosterone decrease could be due to either diminished sensitivity of the testis to plasma LH or increased metabolic rates, while PRA could by modified by changes in the glomerular filtration rate due to the hyperglycemia.
IOD 1. Steroids and the male reproductive system-1 355. lnteractionofhormonalsteroidswithhumanspermatozoa MERCADO, E., REYFS, A. and ROSADO. A., Section Bioquimica de la Reproduction, Departamento de Investigation Cientifica, C.M.N.. lnstituto Mexican0 de1 Social, Apdo. Postal 66-737. Mexico 12, D.F. Diluted suspensions of human sperm ceils when excited with monochromatic light at 288nm emitted a char~~cteristic fluorescence spectrum. This spectrum is quenched when steroid hormones are added to the medium. This quenching effect is evidence that sperm-steroid interaction has occurred. The three steroids studied interact with intact washed human spermatozoa, but testosterone is bound significantly less than oestrone or progesterone (2.5 against 4.5 and 5.0 nmol/ lOh cells respectively). However, the modification of the fluorescence is proportionately greater with testosterone than with the other two steroids, thus indicating a more significant interaction of the androgen with the sperm cells. The association constant of the sperm cell-testosterone complex is also significantly lower (2.76 x 10 -AM) than that ofoestrone(3.96 x 10‘JM)orprogesterone (h-46 x 10 ‘M). Binding of testosterone is then a more reversible process, indicative of a greater responsiveness to environmental changes in hormone concentration.