OBJECTIVETo observe depot medroxyprogesterone acetate (DMPA) and testosterone undecanoate (TU) injected at 8-week intervals for the suppression of spermatogenesis in healthy Chinese men.

METHODSAfter screening, 30 healthy volunteers were enrolled and randomly assigned to 3 dosage-groups (n = 10/group): 1000 mg TU (Group A), 1000 mg TU plus 150 mg DMPA (Group B), 1000 mg TU plus 300 mg DMPA (Group C). All dosages were given as intramuscular injections at 8-week intervals. The study consisted of an 8-week control (baseline) period, a 24-week treatment period and a 24-week recovery period.

RESULTSConsistent azoospermia or severe oligozoospermia was achieved and maintained in all the volunteers during the treatment period, except 2 in the mere TU group who experienced a "rebound" in sperm concentrations. An 8-week regimen of TU plus DMPA at both tested combination dosages effectively suppressed spermatogenesis to azoospermia. All volunteers tolerated the injections; no serious adverse effects were reported.

CONCLUSIONThe lower combined dosage is recommended for further testing in an expanded clinical trial or contraceptive efficacy study.

Adult ; Androgens ; pharmacology ; China ; Gonadotropin-Releasing Hormone ; biosynthesis ; Humans ; Hypothalamo-Hypophyseal System ; metabolism ; Male ; Medroxyprogesterone Acetate ; pharmacology ; Prospective Studies ; Sperm Count ; Spermatogenesis ; drug effects ; Testosterone ; analogs & derivatives ; pharmacology

OBJECTIVETo investigate the effect of Trx-LHRH, a new GnRH crasis protein, on antibody production and male reproductive function.

METHODSTrx-LHRH produced in vitro with a new crasis gene which crasised Trx gene and GnRH gene together, was used as vaccine, and hydroalaminum base as adjuvant, in adult SD rats. After 5 weeks of the first treatment, the same dosage was used again to enhance the effect of vaccine. Antibody level was measured by ELISA, and androgen level by RIA.

RESULTSTrx-LHRH induced successfully the polycolonal antibody at the level of 1 :1 280 approximately 2 560 after 4 weeks of the first treatment, and 1 : 2 000 after 6 weeks of the enhanced treatment. Testosterone level was reduced significantly (P < 0.01) by ELISA, but there was reasonable variation among individuals. Sperm count was also reduced by Trx-LHRH treatment.

CONCLUSIONTrx-LHRH can be used as effective vaccine to induce antibody production, and at the same time, restrain the function of hypothatamas-pituitary-testis axis in vivo.

Animals ; Antibodies ; blood ; Gonadotropin-Releasing Hormone ; immunology ; Male ; Rats ; Rats, Sprague-Dawley ; Recombinant Fusion Proteins ; immunology ; Sperm Count ; Testosterone ; blood ; Thioredoxins ; immunology ; Vaccines, Synthetic ; immunology