Induction of penile erection by intracavernosal and transurethral administration of novel nitric oxide donors in the cat.
OBJECTIVE
The effects of novel nitric oxide (NO) donors administered intracavernosally and transurethrally on erectile function in the anesthetized cat were evaluated.


METHODS
In pentobarbital-anesthetized cats, increases in intracavernosal pressure, penile length, and duration of erectile response were determined after intracavernosal and transurethral injections of novel NO donors (MAHMA/NO, PAPA/NO, DEA/NO, PIPERAZI/NO and PROLI/NO). All parameters were measured after administration of NO donors intracavernosally via a 30-gauge needle and urethrally via a Jelco i.v. catheter in a volume of 200 microliters. Systemic arterial pressure was also assessed in these experiments. All NO donors were compared with a triple-drug control combination comprised of papaverine (1.65 mg.), prostaglandin E1 (0.5 microgram.), and phentolamine (25 micrograms.).


RESULTS
MAHMA/NO, PAPA/NO, DEA/NO, PIPERAZI/NO and PROLI/NO induced dose dependent increases in intracavernosal pressure and penile length (p < 0.05) when administered intracavernosally. The increases in cavernosal pressure and penile length were comparable to those observed with the triple-drug control combination. The maximum increase in cavernosal pressure in response to PROLI/NO and PAPA/NO was associated with no significant change in systemic arterial pressure. Transurethral administration of PROLI/NO and PIPERAZI/NO induced dose-dependent increases in cavernosal pressure and penile length (p < 0.05). The response was similar to that of the triple-drug control combination, except that transurethral PROLI/NO and PIPERAZI/NO had no significant effect on systemic blood pressure.


CONCLUSIONS
NO donors caused dose-dependent increases in cavernosal pressure when administered intracavernosally and transurethrally. These data suggest further exploration of the use of NO donors for the treatment of erectile dysfunction.
Champion
H C
HC
Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana 70112, USA.
Bivalacqua
T J
TJ
Wang
R
R
Kadowitz
P J
PJ
Keefer
L K
LK
Saavedra
J E
JE
Hrabie
J A
JA
Doherty
P C
PC
Hellstrom
W J
WJ
D000818:Animals; D002415:Cats; D004305:Dose-Response Relationship, Drug; D008297:Male; D020030:Nitric Oxide Donors / Q000008:administration & dosage*; D010410:Penile Erection / Q000187:drug effects*; D010413:Penis; D014521:Urethra
D020030:Nitric Oxide Donors