Abstracts 3% Steroid modification of human spermatozoa nuclei metabolism SOSA, A,, CALZADA,L. and ROSADO,A., Secciitn Bioquimica de la Reprodu~i~n, Dep~tamento de fnvestigaci6n Cientifica, Instituto Mexican0 de1 Seguro Social, Apartado Postal S-737, Mtxico 12, D.F. Recent developments in spermatozoa fractionation have permitted us to obtain completely pure isolated nuclei. Since DNA in sperm nuclei seems to be in a highly ordered and possibly energy dependent state, we decided to study the metabolic capacity of isolated human spermatozoa nuclei as well as the response of the latter to biological reagents such as testosterone, oestradiol and progesterone. isolated human sperm nuclei have a detectable basal oxygen uptake (2.4nmol/min/mg DNA) that is modifiedby theadditionofexogenoussubstrates,partic~arly succinate and malate (46 and 4.2nmol/min/mg DNA respectively). This oxygen uptake is able to induce a significant increase in the ATP content of the sperm nuclei (ATPO.12 btmol/hjmg DNA)withaP/OofO.83. Testosterone (10 ~g/ml)increasesATPproduction(O~lS gmoljh/mg DNA) and the P/O ratio without modifying the oxygen uptake. 0estradiol(0.5 pg/ml) stimulated and progesterone (5 pg/ml) depressed oxygen uptake (6.1 and 0.9 nmol/min/mg DNA respectively) without modifying ATP production. 351. Effect of norethandrolone and testosterone on human semen GUTIERREZ,0. and BERNSTEIN,G. S., Section of Reproductive Biology, Department of Obstetrics and Gynaecology, University of Southern California School of Medicine, Los Angeles, California, U.S.A. A group of men received norethandrolone (20 mg daily) and testosterone (80 mg, subdermal implant) for three months as a male contraceptive. The effect of treatment on the semen was evaluated every two weeks. Immunological studies were done to determine whether this therapy, which had no appreciable effect on the sperm count, altered the seminal proteins absorbed on the sperm surface. Washed seminal sperm were treated with antihuman seminal plasma absorbed with serum proteins and a monospecific antilactoferrin immunoserum. The localization of the binding sites was determined by the indirect technique using immunoperoxida~-labelled antibodies. The seminal proteins were localized on the head and midpiece of the sperm while lactoferrin was localized on the sperm head, an essentially normal distribution. It is concluded that this particular regimen does not initialfy cause any major alteration in the distribution of seminal proteins on the sperm surface. 3% Synthesis and secretion of testosterone in rabbits subjected to daily ejaculation DES.JARDINS, C. and EWING, L. L., Department of Zoology, University of Texas, Austin, Texas 78712, and Department of Population Dynamics, Johns Hopkins University. Baltimore, Maryland 21205, U.S.A.
Adult rabbits were sexually rested (SR) or ejaculated once daily for 60 consecutive days (DE) to assess the effects of repeated sexual stimulation on the capacity of the testis to synthesize and secrete testosterone in vitro. Testes (12/
treatment) obtained from rabbits exposed to SR or DE were: (a) Sliced and incubated in 3ml of KRB-buffer, pH 7.4, containing 25 fi Ci “%-sodium acetate with or without gonadotropins (GTH) (1Opg NIH-LH-Sl7~2Oug NIH-FSH-So per flask) to determine testosterone synthesis (B&l Reprod 9:279, 1973); or (b) perfused with artificiai media for 1 h without GTH and with GTH (lpg NIHLH-Sl7+2 @gNNIH-FSH-S8per ml media) for an additional 2 h to determine testosterone secretion (Science 173 : 635, 1971). Testes of SR rabbits synthesized about 55% and 86% more ‘V-testosterone than those of DE animals in the absence and presence of CTH respectively. At the end of the first hour of perfusion, testes of SR and DE rabbits secreted 6.4 and 2.1 and increased to 12.8 and 4.2 pg testosterone/h, respectively, 2 h after GTH stimulation. Plasma of SR rabbits also contained about 50% more testosterone than that of DE animals. It was concluded that DE unequivocally suppressed the capacity of rabbit testes to synthesize and secrete testosterone in vitro and that such changes may occur in v&to since plasma testosterone concentration declined markedly in DE animals. (Supported by NIH Grants HD05795 and HD-07381). 359. Testosterone levels in early fetal testes of domestic pigs RAESIDE,J. I. and SIOMAN,D. M., Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada Biological evidence has been given for androgen secretion by early fetal pig testes in organ culture. In the present study the chemical nature of the androgens produced at sex di~erentia~on was investigated by use of competitive protein binding fCPBl radioassav. The soecificitv of the method for testost&bne &as examiied. Exiracts oi gonads from 155 fetuses (2.0-7.0 cm C-R length) were chromato~aphed on small Celite partition columns before CPB assay. Testosterone was detected in appreciable amounts in gonads from some of the earliest specimens (1.22 ng of testosterone per pair of gonads at 2,Ocm C-R), and the levels seemed to increase with size of fetus (> long of testosterone per pair of gonads at &Ocm C-R). In younger fetuses (2.72.9 cmC-R) where sex was not known, measurement of testosterone was possible in gonads of 11/22 specimens. When sex could be assigned fairly easily from gross appearance (3.0-6.9 cm C-R) it was found that testosterone was measurable in gonads from 41/52 males, l/42 females, and 6/11 where sex was not determined. At this stage of sexual development it appears that tesosterone is not formed by female gonads, but only by the testes of male fetuses. 360. The influence of sex steroids on seiective migratiou of male and female sperms BECK, K. J., S~HWINGER,E. and WEITZEL, H., Frauenklinik und Gerichtsmediz. Institut der Universitgt, Bonn, West Germany Determination of oestradiol-178 and progesterone by radioimmunoassay as well as studies with tritiated sex steroids show that these substances are secreted into the genital fluids (Beck et al.) Further investigations demonstrated that sex steroids were bound to sperms (Ericsson ef al.). Staples ef al., reported an increased proportion of male calves following insemination with oestrogen- and progesteronetreated bovine bull semen. ln the light of these observations, we studied the influence of different sex steroids on the selective migration rate of male and female sperms in vitro.