Apomorphine versus mating behavior in testing erectile capabilities of diabetic rats.
OBJECTIVE
Diabetes mellitus (DM) is an important cause of organic impotence. It is estimated that 35% to 75% of diabetic patients are impotent. In the present study we investigated the effect of experimentally induced diabetes (streptozocin 60 mg/kg, intraperitoneally, for 9 weeks) on sexual behavior and compared it to the apomorphine (APO) bioassay test.


METHODS
Libido, genital reflex excitability, and penile competence as measured by different parameters of mating behavior were reduced with DM (P < 0.05 versus control for each parameter).


RESULTS
Of 17 diabetic rats, 53% (9 rats) experienced positive mating behavior (either intromission or ejaculation) compared with 82.4% (14 rats) positive response to the APO bioassay test. Moreover, combined apomorphine injection and mating sexual testing in diabetic rats that achieved intromission but not ejaculation or those that did not achieve intromission in the initial mating, considerably improved the performance of these rats.


CONCLUSIONS
We suggest that the APO test alone or, even better, combined APO injection and sexual testing are superior in eliciting maximum erectile capabilities of the diabetic rats than mating testing alone.
Elabbady
A
A
Urology Research Laboratory, Royal Victoria Hospital, McGill University, Montreal, Quebec, Canada.
Hassouna
M M
MM
Elhilali
M
M
D000818:Animals; D001058:Apomorphine; D001681:Biological Assay; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D008297:Male; D010410:Penile Erection / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012726:Sexual Behavior, Animal / Q000502:physiology*
D001058:Apomorphine