Geng-Long Hsu - Academia.edu (original) (raw)

Papers by Geng-Long Hsu

Research paper thumbnail of Is coil embolization effective and minimally invasive in young men suffering from veno-occlusive dysfunction?

Journal of vascular and endovascular surgery, Jun 4, 2018

Research paper thumbnail of Analysis of the latest method of penile venous stripping surgery in patient with veno-occlusive dysfunction

Journal of vascular and endovascular surgery, Jun 4, 2018

Research paper thumbnail of A combination of penile venous stripping, corporoplasty and varicocelectomy for patients with erectile dysfunction, penile dysmorphology and varicocele under acupuncture-aided ambulatory local anesthesia

Journal of vascular and endovascular surgery, Jun 4, 2018

Research paper thumbnail of A strategy for glans enhancement and negating glans coldness in patient with penile prosthesis implantation

Journal of vascular and endovascular surgery, Jun 4, 2018

Research paper thumbnail of Penile venous stripping and tunical surgeries for patient with penile dysmorphology and erectile dysfunction under acupuncture-aided local anesthesia on ambulatory basis

Research paper thumbnail of Vascular Surgery for Erectile Dysfunction

Penile vascular surgery for treating erectile dysfunction has been studied in last centuries. Alt... more Penile vascular surgery for treating erectile dysfunction has been studied in last centuries. Although it is not beyond controversy, penile arterial revascularization surgery supports its utility in young males suffered from arterial trauma, and in the older male with localized arterial occlusive disease. Despite it is not agreed in most medical community, penile venous stripping surgery has been shown to be beneficial in correcting veno-occlusive dysfunction, with outstanding results. The traditional complications of irreversible penile numbness and deformity have been virtually negated with the venous ligation technique superseding venous cautery. Penile vascular surgery is viable although it is technically challenging.

Research paper thumbnail of Rat Model for the Study of Penile Erection: Pharmacologic and Electrical-Stimulation Parameters

European Urology, 1994

We report the use of a modified rat model for the study of the mechanisms of penile erection. In ... more We report the use of a modified rat model for the study of the mechanisms of penile erection. In 92 Sprague-Dawley rats, the cavernous nerve was stimulated with different pulse intensities and frequencies, and the intracavernous pressure, time to maximal pressure and total duration of tumescence were measured. A maximal response was elicited at 20 pulses per second (pps) and 1.5 mA. Using this as 100%, we determined the relative pressure responses obtained with other frequencies: 5 pps, 57.3% (p = 0.007), 10 pps, 84.9% (p = 0.043); 30 pps, 99.5% (p = 0.832); 40 pps, 97.8% (p = 0.168); 50 pps, 90.9% (p = 0.021); 100 pps, 76.1% (p < 0.001). The time to maximal pressure varied with different frequencies, but was in all cases significantly different from the 20-pps response. Erection time during continuous cavernous nerve stimulation was significantly longer with frequencies below 20 pps (10 and 5 pps). In 30 rats, the physiologic response to intracavernous injection (0.03 ml) of acetylcholine, atropine, guanethidine, norepinephrine, phenylephrine, papaverine, terbutaline (intravenous also) and phentolamine was measured. Papaverine caused a dose-dependent rise in pressure; acetylcholine, atropine (a parasympathetic blocking agent) and guanethidine all had minimal effects. Phentolamine and norepinephrine increased systemic blood pressure, whereas phenylephrine decreased the intracavernous pressure in response to electrostimulation significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Research paper thumbnail of Formulas for determining the dimensions of venous graft required for penile curvature correction

International Journal of Andrology, Oct 1, 2006

Research paper thumbnail of Combined Cavernous Compression Device and Arteriovenous-Cavernous Fistula: A Chronic Canine Model

The Journal of Urology, Jun 1, 1993

In 5 dogs studied over a 3-month period, we evaluated the chronic effects of the combination of d... more In 5 dogs studied over a 3-month period, we evaluated the chronic effects of the combination of deep dorsal vein arterializatio11 with in1plantation of an inflatable ""v"enous compression device. The device was placed around the proximal corpora cavernosa, sparing the left dorsal artery. A left-to-right, end-to-side dorsal artery-dorsal vein fistula was fashioned, and the right dorsal vein was anastomosed to the corpus cavernosum as an end-to-side venocorporeal window. From postoperative day 15, the device was activated twice a day for 3 months. Intracavernous pressure (bilateral) and left dorsal artery blood flow were monitored, and the patency of the anastomoses was evaluated by vascular clamping, arteriography, cavernosography and microscopic dissection. The device was well-tolerated, requiring no anesthesia during activation. (A sixth dog developed glanular hyperemia and priapism and was excluded from evaluation.) With cuff inflation, the intracavernous pressure was significantly higher on the experimental side (range, 20 to 106 cm. H20 higher; p = 0.028), and arteriography demonstrated contrast flowing in the fistula and window in 3

Research paper thumbnail of Response of Bladder, Urethral and Intracavernous Pressure to Ventral Lumbosacral Root Stimulation in Sprague-Dawley and Wistar Rats

The Journal of Urology, Sep 1, 1992

Six Sprague-Dawley and six Wistar rats were used for electrostimulation of the Ls to 82 ventral r... more Six Sprague-Dawley and six Wistar rats were used for electrostimulation of the Ls to 82 ventral roots, Landmarks for identification of the roots were developed; bladder, urethral and intracavernous pressures were recorded; and tail and leg movements were checked, Urethral sphincter contraction was elicited by stimulation of the Ls-L6 ventral roots, while bladder contraction and penile erection were mediated by the L6-S1 ventral roots, The best sphincteric response and intracavernous pressure rise were obtained by stimulation of the L6 ventral root, and the highest bladder pressures by stimulation of the 8 1 ventral root, Stimulation of the S1-S2 ventral roots provoked ipsilateral tail movement; of L6, tail movement, hindleg muscle twitch, and slight toe spread; and of Ls, hindleg stretch and plantar flexion, No significant differences were found between the two strains of rats, although a higher bladder pressure was recorded during stimulation of the L6 ventral root in Sprague-Dawley rats, which might be explained by a small caudal shift of the sacral parasympathetic nucleus in the Wistar strain,

Research paper thumbnail of A case report of right cardiac ventricle perforation by uncontrolled embolization coil inserted for treating penile veno-occlusive dysfunction

Urology Case Reports

Coil embolization (CE) is believed effective-safe for treating penile veno-occlusive dysfunction ... more Coil embolization (CE) is believed effective-safe for treating penile veno-occlusive dysfunction (VOD). From 2012 to 2016, refractory impotence prompted four men to seek further treatment, although they underwent six CEs elsewhere. Uncontrolled coils scattered along penile drainage veins including the deep dorsal veins (n = 3), periprostatic plexus (n = 1), iliac vein (n = 1), right pulmonary artery (n = 2), left pulmonary artery (n = 1), and right ventricle (n = 1). The last one occurred in a 40-year-old house builder, and the coil perforated the right ventricle wall and diaphragm 18 months later. Given no sustainable improvement, CE's safety and efficacy are unreliable for treating patients with VOD.

Research paper thumbnail of The Penile venous occlusion mechanism: evidence derived from the electrocautery effect to the sinusoids on defrosted human cadavers

Introduction: Azoospermia occurs in 1% of men and in 10–15% of the infertile male population. An ... more Introduction: Azoospermia occurs in 1% of men and in 10–15% of the infertile male population. An obstructive aetiology is found in approximately 40% of azoospermic men. Of these, 30–67% have obstruction at the level of the epididymis. Th is study looks at the outcome of microsurgical epididymovasostomy in the management of obstructive azoospermia, specifi cally the patency and pregnancy rates aft er reconstruction. Patients and Methods: Th e outcome of the microsurgical epididymovasostomy procedures performed between 2000–2011 was retrospectively analysed. Azoospermic patients with normal testicular size, with or without epididymal dilatation, with a normal hormone profi le (FSH, LH, and Testosterone), normal male reproductive genetic profi le (XY), and a TRUS showing no evidence of ejaculatory duct obstruction, underwent scrotal exploration. An intraoperative vasogram was performed to exclude distal obstruction. Scrotal exploration was performed in 124 patients. Th e abscence of di...

Research paper thumbnail of The Role of Cyclic Adenosine Monophosphate, Cyclic Guanosine Monophosphate, Endothelium and Nonadrenergic, Noncholinergic Neurotransmission in Canine Penile Erection

Research paper thumbnail of Structural alterations in the tunica albuginea of the penis: impact of Peyronie's disease, ageing and impotence

British Journal of Urology, 1997

Objective To investigate whether changes in the structure of the tunica albuginea influence the ... more Objective To investigate whether changes in the structure of the tunica albuginea influence the development of erectile dysfunction. Patients and methods Biopsy specimens taken from the tunica of 64 patients (both potent and impotent) with and without Peyronie's disease were evaluated. Tissue samples were stained and examined under light and electron microscopy, and the concentration of elastic fibres present in each was measured using computerized image analysis. Results The concentration of elastic fibres was lower in impotent than in potent patients (P=0.0365) and was also significantly less in patients with Peyronie's disease. Furthermore, the concentration of elastic fibres decreased with age. Electron and light microscopy revealed the presence of distinct alterations in the tunica albuginea in impotent patients and patients with Peyronie's disease that might interfere with function. Conclusion The decrease in elastic fibre concentration and changes in microscop...

Research paper thumbnail of Can a venous patch graft be a substitute for the tunica albuginea of the penis?

The Journal of Urology, Oct 1, 1993

We describe our experience with plaque excision and placement of a venous patch graft. Sprague Da... more We describe our experience with plaque excision and placement of a venous patch graft. Sprague Dawley rats (n = 20) underwent excision of a wedge of tunica albuginea with the defect covered by a segment of detubularized femoral vein, endothelial side towards the cavernous tissue. Erectile function, as determined by the rise in intracavernous pressure with cavernous nerve stimulation (mean 54.0 ± 4.2 cm. H 2 0), was equal to that in a group of 10 intact age-matched controls (mean 46.9 ± 3.37 cm. H 2 0). Penile cross-sections stained with Hart's elastic fiber stain or Trichrome stain revealed only minimal fibrosis in the region of the patch. In 3 dogs, a wedge of tunica was removed, and the defect was covered with a segment of detubularized deep dorsal vein. When sacrificed at 3 months, all animals had retained their erectile function with histologic evidence of minimal fibrosis. On the basis of histologic and functional data, the venous patch appears to be a reasonable alternative substance to those in common use.

Research paper thumbnail of Traumatic Glans Deformity

The Journal of Urology, Oct 1, 2001

Research paper thumbnail of Role of Doppler ultrasound in the evaluation of penile hemodynamics in male impotence

Taiwan yi xue hui za zhi. Journal of the Formosan Medical Association, 1988

Research paper thumbnail of A physiological approach of penile venous stripping for patients with erectile dysfunction on ambulatory basis

Journal of vascular and endovascular surgery, Jun 4, 2018

Research paper thumbnail of Cyclic Guanosine Monophosphate Mediates Penile Erection in the Rat

European Urology, 1993

Recent in vivo and in vitro studies suggest that nitric oxide or a nitric-oxide-like substance me... more Recent in vivo and in vitro studies suggest that nitric oxide or a nitric-oxide-like substance mediates nonadrenergic, noncholinergic relaxation of trabecular smooth muscle through activation of the cyclic guanosine monophosphate (cGMP) pathway. In 60 Sprague-Dawley rats, we investigated the effect of intracavernous administration of different drugs known to act at different levels of the cyclic adenosine monophosphate (cAMP) and cGMP pathways. Neither cAMP nor drugs that stimulate adenylate cyclase activity (vasoactive intestinal peptide, prostaglandin E1, calcitonin gene-related peptide) provoked any change in the basal intracavernous pressure. N-ethylmaleimide, an inhibitor of the enzyme adenylate cyclase, did not modify the response to electrostimulation of the cavernous nerve, indicating that the cAMP pathway does not play a significant role in penile erection in rats. However, intracavernous administration of methylene blue, a guanylate cyclase inhibitor, significantly reduced the response to electrostimulation (p = 0.001). Direct intracavernous injection of cGMP caused a statistically significant, dose-dependent increase in intravenous pressure that was not significantly inhibited by methylene blue. Sodium nitroprusside, a nitric oxide releaser and therefore a guanylate cyclase activator, caused a dose-dependent increase in intracavernous pressure (p < 0.05) that was inhibited almost completely by methylene blue (p = 0.002), supporting the theory that nitric oxide activates the synthesis of cGMP and that cGMP causes cavernous smooth muscle relaxation. Papaverine elicited an intracavernous pressure increase that was not affected by methylene blue or N-ethylmaleimide, indicating that papaverine acts through an independent pathway.(ABSTRACT TRUNCATED AT 250 WORDS)

Research paper thumbnail of Herb formula enhances treatment of impotent patients after penile venous stripping: a randomised clinical trials

Andrologia, Jan 20, 2015

Herbs have been regarded as aphrodisiacs in treating impotence for many centuries despite little ... more Herbs have been regarded as aphrodisiacs in treating impotence for many centuries despite little true scientific evidence. Our latest refined penile venous stripping (PVS) technique is effective in treating impotence, although this procedure remains controversial. A synergic effect of PVS and oral herbs was confirmed in our practice but lacked rigorous scientific proof. The objective of this report was to review our experience with this combination. From August 2010 to May 2014, 263 males underwent PVS. Among these, 67 unsatisfied men chose additional salvage therapy and were randomly assigned to oral herbs (n = 35) or placebo treatment (n = 32) which replaced herb eventually. All were evaluated with the international index of erectile function (IIEF-5) scoring and our dual pharmaco-cavernosography. The pre-op IIEF-5 score for the herb group was 9.7 ± 3.7, post-operative 13.9 ± 3.3 and post-herb 19.6 ± 3.4, while the control group scores were as follows: pre-op 9.3 ± 4.1, post-op 14...

Research paper thumbnail of Is coil embolization effective and minimally invasive in young men suffering from veno-occlusive dysfunction?

Journal of vascular and endovascular surgery, Jun 4, 2018

Research paper thumbnail of Analysis of the latest method of penile venous stripping surgery in patient with veno-occlusive dysfunction

Journal of vascular and endovascular surgery, Jun 4, 2018

Research paper thumbnail of A combination of penile venous stripping, corporoplasty and varicocelectomy for patients with erectile dysfunction, penile dysmorphology and varicocele under acupuncture-aided ambulatory local anesthesia

Journal of vascular and endovascular surgery, Jun 4, 2018

Research paper thumbnail of A strategy for glans enhancement and negating glans coldness in patient with penile prosthesis implantation

Journal of vascular and endovascular surgery, Jun 4, 2018

Research paper thumbnail of Penile venous stripping and tunical surgeries for patient with penile dysmorphology and erectile dysfunction under acupuncture-aided local anesthesia on ambulatory basis

Research paper thumbnail of Vascular Surgery for Erectile Dysfunction

Penile vascular surgery for treating erectile dysfunction has been studied in last centuries. Alt... more Penile vascular surgery for treating erectile dysfunction has been studied in last centuries. Although it is not beyond controversy, penile arterial revascularization surgery supports its utility in young males suffered from arterial trauma, and in the older male with localized arterial occlusive disease. Despite it is not agreed in most medical community, penile venous stripping surgery has been shown to be beneficial in correcting veno-occlusive dysfunction, with outstanding results. The traditional complications of irreversible penile numbness and deformity have been virtually negated with the venous ligation technique superseding venous cautery. Penile vascular surgery is viable although it is technically challenging.

Research paper thumbnail of Rat Model for the Study of Penile Erection: Pharmacologic and Electrical-Stimulation Parameters

European Urology, 1994

We report the use of a modified rat model for the study of the mechanisms of penile erection. In ... more We report the use of a modified rat model for the study of the mechanisms of penile erection. In 92 Sprague-Dawley rats, the cavernous nerve was stimulated with different pulse intensities and frequencies, and the intracavernous pressure, time to maximal pressure and total duration of tumescence were measured. A maximal response was elicited at 20 pulses per second (pps) and 1.5 mA. Using this as 100%, we determined the relative pressure responses obtained with other frequencies: 5 pps, 57.3% (p = 0.007), 10 pps, 84.9% (p = 0.043); 30 pps, 99.5% (p = 0.832); 40 pps, 97.8% (p = 0.168); 50 pps, 90.9% (p = 0.021); 100 pps, 76.1% (p < 0.001). The time to maximal pressure varied with different frequencies, but was in all cases significantly different from the 20-pps response. Erection time during continuous cavernous nerve stimulation was significantly longer with frequencies below 20 pps (10 and 5 pps). In 30 rats, the physiologic response to intracavernous injection (0.03 ml) of acetylcholine, atropine, guanethidine, norepinephrine, phenylephrine, papaverine, terbutaline (intravenous also) and phentolamine was measured. Papaverine caused a dose-dependent rise in pressure; acetylcholine, atropine (a parasympathetic blocking agent) and guanethidine all had minimal effects. Phentolamine and norepinephrine increased systemic blood pressure, whereas phenylephrine decreased the intracavernous pressure in response to electrostimulation significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Research paper thumbnail of Formulas for determining the dimensions of venous graft required for penile curvature correction

International Journal of Andrology, Oct 1, 2006

Research paper thumbnail of Combined Cavernous Compression Device and Arteriovenous-Cavernous Fistula: A Chronic Canine Model

The Journal of Urology, Jun 1, 1993

In 5 dogs studied over a 3-month period, we evaluated the chronic effects of the combination of d... more In 5 dogs studied over a 3-month period, we evaluated the chronic effects of the combination of deep dorsal vein arterializatio11 with in1plantation of an inflatable ""v"enous compression device. The device was placed around the proximal corpora cavernosa, sparing the left dorsal artery. A left-to-right, end-to-side dorsal artery-dorsal vein fistula was fashioned, and the right dorsal vein was anastomosed to the corpus cavernosum as an end-to-side venocorporeal window. From postoperative day 15, the device was activated twice a day for 3 months. Intracavernous pressure (bilateral) and left dorsal artery blood flow were monitored, and the patency of the anastomoses was evaluated by vascular clamping, arteriography, cavernosography and microscopic dissection. The device was well-tolerated, requiring no anesthesia during activation. (A sixth dog developed glanular hyperemia and priapism and was excluded from evaluation.) With cuff inflation, the intracavernous pressure was significantly higher on the experimental side (range, 20 to 106 cm. H20 higher; p = 0.028), and arteriography demonstrated contrast flowing in the fistula and window in 3

Research paper thumbnail of Response of Bladder, Urethral and Intracavernous Pressure to Ventral Lumbosacral Root Stimulation in Sprague-Dawley and Wistar Rats

The Journal of Urology, Sep 1, 1992

Six Sprague-Dawley and six Wistar rats were used for electrostimulation of the Ls to 82 ventral r... more Six Sprague-Dawley and six Wistar rats were used for electrostimulation of the Ls to 82 ventral roots, Landmarks for identification of the roots were developed; bladder, urethral and intracavernous pressures were recorded; and tail and leg movements were checked, Urethral sphincter contraction was elicited by stimulation of the Ls-L6 ventral roots, while bladder contraction and penile erection were mediated by the L6-S1 ventral roots, The best sphincteric response and intracavernous pressure rise were obtained by stimulation of the L6 ventral root, and the highest bladder pressures by stimulation of the 8 1 ventral root, Stimulation of the S1-S2 ventral roots provoked ipsilateral tail movement; of L6, tail movement, hindleg muscle twitch, and slight toe spread; and of Ls, hindleg stretch and plantar flexion, No significant differences were found between the two strains of rats, although a higher bladder pressure was recorded during stimulation of the L6 ventral root in Sprague-Dawley rats, which might be explained by a small caudal shift of the sacral parasympathetic nucleus in the Wistar strain,

Research paper thumbnail of A case report of right cardiac ventricle perforation by uncontrolled embolization coil inserted for treating penile veno-occlusive dysfunction

Urology Case Reports

Coil embolization (CE) is believed effective-safe for treating penile veno-occlusive dysfunction ... more Coil embolization (CE) is believed effective-safe for treating penile veno-occlusive dysfunction (VOD). From 2012 to 2016, refractory impotence prompted four men to seek further treatment, although they underwent six CEs elsewhere. Uncontrolled coils scattered along penile drainage veins including the deep dorsal veins (n = 3), periprostatic plexus (n = 1), iliac vein (n = 1), right pulmonary artery (n = 2), left pulmonary artery (n = 1), and right ventricle (n = 1). The last one occurred in a 40-year-old house builder, and the coil perforated the right ventricle wall and diaphragm 18 months later. Given no sustainable improvement, CE's safety and efficacy are unreliable for treating patients with VOD.

Research paper thumbnail of The Penile venous occlusion mechanism: evidence derived from the electrocautery effect to the sinusoids on defrosted human cadavers

Introduction: Azoospermia occurs in 1% of men and in 10–15% of the infertile male population. An ... more Introduction: Azoospermia occurs in 1% of men and in 10–15% of the infertile male population. An obstructive aetiology is found in approximately 40% of azoospermic men. Of these, 30–67% have obstruction at the level of the epididymis. Th is study looks at the outcome of microsurgical epididymovasostomy in the management of obstructive azoospermia, specifi cally the patency and pregnancy rates aft er reconstruction. Patients and Methods: Th e outcome of the microsurgical epididymovasostomy procedures performed between 2000–2011 was retrospectively analysed. Azoospermic patients with normal testicular size, with or without epididymal dilatation, with a normal hormone profi le (FSH, LH, and Testosterone), normal male reproductive genetic profi le (XY), and a TRUS showing no evidence of ejaculatory duct obstruction, underwent scrotal exploration. An intraoperative vasogram was performed to exclude distal obstruction. Scrotal exploration was performed in 124 patients. Th e abscence of di...

Research paper thumbnail of The Role of Cyclic Adenosine Monophosphate, Cyclic Guanosine Monophosphate, Endothelium and Nonadrenergic, Noncholinergic Neurotransmission in Canine Penile Erection

Research paper thumbnail of Structural alterations in the tunica albuginea of the penis: impact of Peyronie's disease, ageing and impotence

British Journal of Urology, 1997

Objective To investigate whether changes in the structure of the tunica albuginea influence the ... more Objective To investigate whether changes in the structure of the tunica albuginea influence the development of erectile dysfunction. Patients and methods Biopsy specimens taken from the tunica of 64 patients (both potent and impotent) with and without Peyronie's disease were evaluated. Tissue samples were stained and examined under light and electron microscopy, and the concentration of elastic fibres present in each was measured using computerized image analysis. Results The concentration of elastic fibres was lower in impotent than in potent patients (P=0.0365) and was also significantly less in patients with Peyronie's disease. Furthermore, the concentration of elastic fibres decreased with age. Electron and light microscopy revealed the presence of distinct alterations in the tunica albuginea in impotent patients and patients with Peyronie's disease that might interfere with function. Conclusion The decrease in elastic fibre concentration and changes in microscop...

Research paper thumbnail of Can a venous patch graft be a substitute for the tunica albuginea of the penis?

The Journal of Urology, Oct 1, 1993

We describe our experience with plaque excision and placement of a venous patch graft. Sprague Da... more We describe our experience with plaque excision and placement of a venous patch graft. Sprague Dawley rats (n = 20) underwent excision of a wedge of tunica albuginea with the defect covered by a segment of detubularized femoral vein, endothelial side towards the cavernous tissue. Erectile function, as determined by the rise in intracavernous pressure with cavernous nerve stimulation (mean 54.0 ± 4.2 cm. H 2 0), was equal to that in a group of 10 intact age-matched controls (mean 46.9 ± 3.37 cm. H 2 0). Penile cross-sections stained with Hart's elastic fiber stain or Trichrome stain revealed only minimal fibrosis in the region of the patch. In 3 dogs, a wedge of tunica was removed, and the defect was covered with a segment of detubularized deep dorsal vein. When sacrificed at 3 months, all animals had retained their erectile function with histologic evidence of minimal fibrosis. On the basis of histologic and functional data, the venous patch appears to be a reasonable alternative substance to those in common use.

Research paper thumbnail of Traumatic Glans Deformity

The Journal of Urology, Oct 1, 2001

Research paper thumbnail of Role of Doppler ultrasound in the evaluation of penile hemodynamics in male impotence

Taiwan yi xue hui za zhi. Journal of the Formosan Medical Association, 1988

Research paper thumbnail of A physiological approach of penile venous stripping for patients with erectile dysfunction on ambulatory basis

Journal of vascular and endovascular surgery, Jun 4, 2018

Research paper thumbnail of Cyclic Guanosine Monophosphate Mediates Penile Erection in the Rat

European Urology, 1993

Recent in vivo and in vitro studies suggest that nitric oxide or a nitric-oxide-like substance me... more Recent in vivo and in vitro studies suggest that nitric oxide or a nitric-oxide-like substance mediates nonadrenergic, noncholinergic relaxation of trabecular smooth muscle through activation of the cyclic guanosine monophosphate (cGMP) pathway. In 60 Sprague-Dawley rats, we investigated the effect of intracavernous administration of different drugs known to act at different levels of the cyclic adenosine monophosphate (cAMP) and cGMP pathways. Neither cAMP nor drugs that stimulate adenylate cyclase activity (vasoactive intestinal peptide, prostaglandin E1, calcitonin gene-related peptide) provoked any change in the basal intracavernous pressure. N-ethylmaleimide, an inhibitor of the enzyme adenylate cyclase, did not modify the response to electrostimulation of the cavernous nerve, indicating that the cAMP pathway does not play a significant role in penile erection in rats. However, intracavernous administration of methylene blue, a guanylate cyclase inhibitor, significantly reduced the response to electrostimulation (p = 0.001). Direct intracavernous injection of cGMP caused a statistically significant, dose-dependent increase in intravenous pressure that was not significantly inhibited by methylene blue. Sodium nitroprusside, a nitric oxide releaser and therefore a guanylate cyclase activator, caused a dose-dependent increase in intracavernous pressure (p < 0.05) that was inhibited almost completely by methylene blue (p = 0.002), supporting the theory that nitric oxide activates the synthesis of cGMP and that cGMP causes cavernous smooth muscle relaxation. Papaverine elicited an intracavernous pressure increase that was not affected by methylene blue or N-ethylmaleimide, indicating that papaverine acts through an independent pathway.(ABSTRACT TRUNCATED AT 250 WORDS)

Research paper thumbnail of Herb formula enhances treatment of impotent patients after penile venous stripping: a randomised clinical trials

Andrologia, Jan 20, 2015

Herbs have been regarded as aphrodisiacs in treating impotence for many centuries despite little ... more Herbs have been regarded as aphrodisiacs in treating impotence for many centuries despite little true scientific evidence. Our latest refined penile venous stripping (PVS) technique is effective in treating impotence, although this procedure remains controversial. A synergic effect of PVS and oral herbs was confirmed in our practice but lacked rigorous scientific proof. The objective of this report was to review our experience with this combination. From August 2010 to May 2014, 263 males underwent PVS. Among these, 67 unsatisfied men chose additional salvage therapy and were randomly assigned to oral herbs (n = 35) or placebo treatment (n = 32) which replaced herb eventually. All were evaluated with the international index of erectile function (IIEF-5) scoring and our dual pharmaco-cavernosography. The pre-op IIEF-5 score for the herb group was 9.7 ± 3.7, post-operative 13.9 ± 3.3 and post-herb 19.6 ± 3.4, while the control group scores were as follows: pre-op 9.3 ± 4.1, post-op 14...