GAMETE BIOLOGY AND GAMETOGENESIS - C
Wednesday, August 4, 2004
10:30 AM–12:30 PM
(701) COMPARISON OF HOST ENDOCRINE ENVIRONMENT AND DONOR AGE ON SPERMATOGENESIS IN ECTOPIC TESTIS GRAFTS.
Adams, Homer1, 2, McLean, Derek1, 2, 1 Washington State University, Pullman, WA, USA2 Washington State University, Pullman, WA, USA
ABSTRACT- Testicular grafting has been used to provide alternative means to investigate spermatogenesis in non-testis environments. This technique could lead to identification of infertility factors and sperm from cancer treated patients. Ectopic testis grafting in different species has demonstrated multiple factors may affect sperm production. The objective of this study was to identify host endocrine factors that influence sperm production in ectopic testis grafts. Intact or gonadectomized male and female nude mice were used as recipients for testis allografts from neonatal mice. In addition, the durations of the grafts, 35 or 70 days, and the age of donor tissue 0-5, 6-10, and 11-15 days post partum (dpp) were examined to find parameters for sperm production in grafts. Graft weight, testosterone levels, seminal vesicle weight and percentage of seminiferous tubules with elongated spermatids were endpoints of analysis. It was found that testosterone was present in all of the mice indicating Leydig cell function within the grafts. At 70 days post graft, the seminal vesicle weights of castrated and intact recipients were similar indicating graft testosterone production. Testis tissue from 0-5 dpp mice had the greatest weight increase at 70d in all recipients, while gonadectomized recipients had a higher graft weight than intact animals. Donor tissue from 0-5 and 11-15 dpp grafted to castrated recipients had the highest percentage of elongated spermatids while donor tissue from 0-5 dpp grafted for 70d on ovariectomized mice displayed a higher percentage of elongates than any intact male group. From this study, grafts from ovariectomized females produced sperm as well as grafts on male intact recipients and similar to grafts on castrated mice, indicating they are suitable testis graft hosts. The best parameters for testis graft elongate spermatid production in male and ovariectomized recipients were donor tissue of 0-5 or 11-15 dpp and 70d grafting period. This is the first study in which multiple age ranges were used as testis donors for ectopic grafting. Implications of this work indicate the extent that donor testis differentiation and host environment may impact sperm production in grafts. HA was supported by a generous gift from the ARCS Foundation.
KEY WORDS: sperm, spermatogenesis, testis, testosterone