Chronic suppression of testicular function by constant infusion of gonadotropin-releasing hormone agonist and testosterone supplementation in the bonnet monkey (Macaca radiata).
OBJECTIVE
To study the efficacy of long-term buserelin acetate infusion to desensitize pituitary and block testicular function in adult male monkeys (Macaca radiata).


METHODS
Proven fertile male monkeys exhibiting normal testicular function.


METHODS
Each of the control (n = 5) and experimental monkeys (n = 10) received a fresh miniosmotic pump every 21 days, whereas pumps in controls delivered vehicle of experimentals released 50 micrograms buserelin acetate every 24 hours. On day 170 (renewed every 60 days) a silastic capsule containing crystalline testosterone (T) was implanted in the experimental monkeys. At the end of 3 years, treatment was stopped, and recovery of testicular function and fertility monitored.


RESULTS
(1) Treatment resulted in marked reduction of nocturnal but not basal serum T; (2) the pituitary remained desensitized to buserelin acetate throughout the 3-year period; (3) animals were largely azoospermic with occasional oligospermia exhibited by two monkeys; and (4) withdrawal of treatment restored testicular function, with 70% of animals regaining fertility.


CONCLUSIONS
Long-term infertility (but restorable) can be induced in male monkeys by constant infusion of buserelin acetate and T.
Ravindranath
N
N
Indian Institute of Science, Bangalore.
Ramesh
V
V
Krishnamurthy
H N
HN
Rao
A J
AJ
Moudgal
R N
RN
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003692:Delayed-Action Preparations; D004343:Drug Implants; D007987:Gonadotropin-Releasing Hormone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D007262:Infusions, Intravenous; D008255:Macaca radiata; D008297:Male; D009929:Organ Size / Q000187:drug effects; D012016:Reference Values; D013076:Sperm Count / Q000187:drug effects; D013737:Testis / Q000187:drug effects / Q000502:physiology*; D013739:Testosterone / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D017329:Triptorelin Pamoate / Q000031:analogs & derivatives*
D003692:Delayed-Action Preparations; D004343:Drug Implants; D017329:Triptorelin Pamoate; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; C019176:Tryptal