Role of Nitric Oxide in the Relaxation of Rabbit Vaginal Smooth Muscle / 대한비뇨기과학회지

PURPOSE: Vaginal engorgement depends, in part, on the relaxation of vaginal smooth muscle. The aim of this study was to evaluate the role of nitric oxide(NO) in the relaxation of the vaginal smooth muscle. MATERIALS AND METHODS: New Zealand White female rabbits(n=8) were sacrificed and distal 1/3 of the vagina was dissected. Strips of vaginal tissues were immediately processed for isometric tension measurement in the organ bath. The vaginal strips were precontracted with phenylephrine and the responses to electrical field stimulation(EFS) or sodium nitroprusside were examined. Each preparations was also processed immunohistochemically to determine the presence of neuronal NO synthase(n-NOS) in the tissue. RESULTS: EFS caused a frequency-dependent relaxation, which was significantly inhibited in the presence of Nw-nitro-L-arginine methyl ester(L-NAME), a competitive inhibitor of NOS. Sodium nitroprusside, a NO donor, caused concentration-dependent relaxations in the vaginal tissue and the relaxation was not affected by L-NAME(10-4M). n-NOS immunoreactivity was detected in perivascular space and vicinity of vaginal smooth muscle. CONCLUSIONS: These results suggest that the relaxation of the rabbit vaginal smooth muscle is partly mediated by the NO pathway.

Real-Time Audio-Visual Sexual Stimulation with Eyeglasses-Type Monitor Improves Quality of Drug-Induced Erection during Penile Duplex Doppler Ultrasonography / 대한남성과학회지

PURPOSE: Intracavernosal injection subsequent vibrotactile or audiovisual sexual stimulation (AVSS) have frequently been utilized to produce al maximal erectile response during penile Doppler ultrasonography. However, several studies have shown that erectile quality often decreases following the placement of the sonographic probe. We examined whether real-time AVSS with an eyeglasses-type monitor enhances quality during penile duplex color Doppler ultrasonography. PATIENTS AND METHODS: A total of 32 impotent patients underwent penile duplex color Doppler ultrasonography of the cavernosal arteries after intracavernosal injection of 10 to 20 microgram of prostaglandin E1 and subsequent manual stimulation. Real-time AVSS sas used when the patient failed to achieve a rigid erection or showed abnomal arterial blood flow. The clinical erectile response was assessed by visual inspection and palpation and graded from I to V. Peak blood flow velocities and resistance index of the both cavernosal arteries were monitored continuously. After AVSS, the sexual drive was assessed as grade I (poor), II (moderate), or III (good). RESULTS: After intracavernosal injection and genital stimulation, 3 patients (9%) had a Grade II erection, 2 (6%) a Grade III, 16 (50%) a Grade IV, and 11 (34%) a Grade V. During duplex ultrasonography, 4 patients (13%) had a Grade II erection, 7 (22%) a Grade III, 16 (50%) a Grade IV, and 5 (16%) an arade V. During real-time AVSS, 22 patients (69%) showed better drectile quality. Initial Doppler ultrasonographic scanning showed arteriogenic impotence in 9 patients (28%), veno-occlusive disease in 5 (16%), and mixed arteriogenic and venogenic impotence in 18 (25%), veno-occlusive in 9 (28%), and mixed type in 2 (6%). Therefore, the initial diagnosis turned to be different after AVSS in 26 patients (81%). The sexual drive was rated grade I in 9 (28%), grade II in 11(34%), and grade III in 12 (38%). CONCLUSION: Real-time AVSS with an eyeglasses-type monitor remarkably enhances the quality of pharmacologically induced erections. Such stimulation may be useful during penile color Doppler ultrasonography to help in making the ccorrect diagnosis of the cause of erectile dysfunction.