It has recently been reported that both norepinephrine and dopamine elicit antidiuresis when given intracerebroventricularly. But no inference has been made as to their mechanisms. As dopamine is the immediate precursor of norepinephrine in the biosynthesis of catecholamine, it might be possible that dopamine might act indirectly through increased level of norepinephrine in the brain tissue. To certify whether the dopamine-induced antidiuresis is related to norepinephrine, the influence of phentolamine, a specific alpha-adrenergic blocking agent, on the centrally induced antidiuresis of both norepinephrine and dopamine was investigated in this study. Norepinephrine and dopamine given intraventricularly elicited maximal antidiuresis in doses of 10ug and 500ug, respectively. Phentolamine, administered intravenously in dose of 2mg/kg, abolished the renal effect of norepinephrine given intraventricularly, but did not influence the antidiuresis induced by dopamine. It is suggested that both norepinephrine and dopamine produce antidiuresis when given intracerebroventricularly but their actions are mediated by different mechanisms, and that norepinephrine does not participate in the renal action of dopamine.
Brain ; Dopamine* ; Norepinephrine* ; Phentolamine*

An in vitro pharmacologic study was conducted to investigate the effect of phentolamine on norepinephrine induced contraction of human corpus cavernosum. The isometric muscle tension of corpus cavernosum from 4 potent volunteers were recorded after stimulation with various concentrations of norepinephrine and phentolamine. The results are summarized as follows. Contractile response of corpus cavernosum was observed to begin in the concentration of 10(-6) M and to reach maximal level in the concentration of 10(-4)M norepinephrine. Compared to it, contractile activity of corpus cavernosum to norepinephrine was observed to be gradually decreased in response to pretreatment with phentolamine from 10(-6)M to 10(-4)M. These indicate that norepinephrine causes a dose dependent contraction of corpus cavernosum and phentolamine had a relaxant effect on norepinephrine-induced contraction of corpus cavernosum in dose dependent manner.
Humans ; Muscle Tonus ; Norepinephrine* ; Phentolamine* ; Volunteers

PURPOSE: This study was aimed to compare the erectile response when phentolamine of intracavernous trimix(papaverine, phentolamine, alprostadil) was replaced with chlorpromazine. MATERIALS AND METHODS: A total of 65 patients with erectile dysfunction(63.3+/-9.19 years of age) who had already used intracavernous injection with trimix(4.5+/-2.12 years) were recruited for this study. The erection quality and adverse reactions of chlorpromazine solution were compared with those of trimix. RESULTS: Among 65 patients, the erection quality of the intracavernous chlorpromazine solution compared to that of trimix was worse in 26 patients(40%), better in 8(12.3%) and similar in 31(47.7%) when injected at the clinic. Among 45 patients who used the chlorpromazine solution for intracavernous self-injection at home for more than 3 months, however, the erection quality was worse in 13(28.9%), better in 8(17.8%) and similar in 24(53.3%). Intracavernous chlorpromazine solution-either injected at the clinic or self-injected-showed no significant adverse reaction. CONCLUSIONS: Chlorpromazine could be a safe and effective substitude of phentolamine of trimix.
Alprostadil* ; Chlorpromazine* ; Erectile Dysfunction ; Humans ; Male ; Papaverine* ; Phentolamine

The effects of intraventricular atropine on the heart rate was investigated in the rabbit. Intraventricular administration of atropine in a dose of 10, 30, 100, or 300 ug produced dose dependant bradycardia. Atropine (100 ug) induced bradycardia was abolished by bilateral vagotomy or intravenous atropine, and inhibited by intravenous propranolol but not by intravenous Regitine. Intraventricular Ecolid or regitine pretreatment diminished the bradycardia induced by intraventricular atropine. From the above results, it is suggested that a central adrenergic mechanism as well as vagal activity plays an important role in the intraventricular atropine-induced bradycardia.
Atropine* ; Bradycardia ; Chlorisondamine ; Heart Rate* ; Heart* ; Phentolamine ; Propranolol ; Vagotomy

PURPOSE: To compare the efficacy of Bimix solution (27.3 mg/ml papaverine and 0.9 mg/ml phentolamine) versus Trimix solution (18.8 mg/ml papaverine, 0.6 mg/ml phentolamine and 6.3ug/ml prostaglandin El) in terms of erectile response and complications. MATERIALS AND METHODS: We comparatively analyzed the erectile response and the incidence of pain, prolonged erection (>4 hours), and corporal fibrosis of either medication in the 155 impotent patients who used Bimix solution for intracavernous pharmacotherapy (mean duration: 15 months) and thereafter used Trimix solution (mean 12 months). RESULTS: Erectile response to Trimix solution was significantly better than Bimix solution (p<0.01). The mean dose of Bimix solution was higher than Trimix solution (0.43 ml. vs. 0.34 ml, p<0.05). The severe pain enough for impediment to ntercourse occurred in 6.5% of the Trimix group, while no patient of the Bimix group experienced (p<0.01). The corporal fibrosis was noted in 8.4% of the Trimix group and 16.1% of the Bimix group. However, there was no significant difference between the two groups (p=0.08). The incidence of prolonged erection was significantly lower (p<0.05) in the Trimix group (2.6%) than in the Bimix group (12.3%). A total of 139 patients (89.7%) finally selected Trimix solution. CONCLUSIONS: The Trimix solution was more effective and safer than Bimix solution for the treatment of erectile dysfunction.
Drug Therapy ; Erectile Dysfunction* ; Fibrosis ; Humans ; Incidence ; Male ; Papaverine ; Phentolamine

1. It was attempted to clarify the mechanism of the pressor response to raised intracranial pressure in urethane-anesthetized rabbits. 2. Intraventricular clonidine markedly inhibited the pressor response to raised intracranial pressure. 3. Intraventricular regitine antagonized the above mentioned inhibitory effect of clonidine on the pressor response. 4. In reserpine-treated rabbits the pressor response to raised intracranial pressure was not observed, whereas after the intraventricular administration of norepinephrine the pressor response was observed. 5. Intraventricular clonidine inhibited the pressor response that could be observed in the reserpine-treated rabbits after the intraventricular norepinephrine. 6. It is inferred that raised intracranial pressure stimulated some part of the brain to cause the increase of norepinephrine release, resulting in the increase of the sympathetic outflow and the elevation of blood pressure.
Blood Pressure ; Brain ; Clonidine* ; Intracranial Pressure* ; Norepinephrine ; Phentolamine* ; Rabbits*

Effects of several autonomic drugs on the responses of the isolated rabbit detrusor muscle strips to electrical stimulation were investigated. Electric stimulation of the detrusor muscle strips elicited two different responses; (a) contraction followed by relaxation in 14 cases out of 22 experiments, and (b) contraction only in 8 cases. The contraction responses to electrical stimulation were significantly reduced in the presence of either atropine or regitine, respectively The relaxation response to electrical stimulation was abolished in the presence of propranolol. Addition of norepinephrine evoked one of following three responses: (a) relaxation in 10 cases out of 19 experiments, (b) contraction in 6 cases, and (c) contraction followed by relaxation in 4 cases. The relaxation response to norepinephrine was reversed. in the presence of propranolol, to a contraction response which was then abolished after administration of regitine. The contraction response to norepinephrine was reversed, in the presence of regitine, to a relaxation response which was then abolished after administration of propranolol. Acetylcholine elicited contraction of the isolated detrusor muscle strip, and this was abolished in the presence of atropine These results suggest that the rabbit detrusor muscle is innervated by both cholinergic and adrenergic fibers and that the detrusor muscle contains cholinergic receptors as well as adrenergic a-and b-ones. Contrary to the popular opinion that the detrusor muscle predominantly contains adrenergic b-receptors, it seems likely that the adrenergic receptors differ in predominancy of either a or b which elicits contraction or relaxation, respectively, according to different areas of the muscle.
Acetylcholine ; Adrenergic Fibers ; Atropine ; Autonomic Agents* ; Electric Stimulation* ; Norepinephrine ; Phentolamine ; Propranolol ; Receptors, Adrenergic ; Receptors, Cholinergic ; Relaxation

BACKGROUND: Exercise-induced coronary spasm is occasionally recognized in patients with variant angina, but the patterns of exercise-induced coronary spasm and its relation to clinical features are still not clear. METHODS: Eight consecutive patients with variant angina without significant stenosis of the coronary artery performed serial treadmill exercise tests during early morning, late morning, and in the afternoon. The subjects repeated the tests after administration of atropine and doxazosin or phentolamine. RESULTS: (Upon drug administration), anginal episodes with ST-segment changes (elevation 5, depression 1) Occurred repeatedly in 6 of the 8 patients during early morning; the episodes occurred in only 2 patients during the afternoon exercise test. Four patients showed exercise-induced angina and ST-segment changes during early morning but not in the afternoon, and 2 of them showed mild episodes of exercise-induced angina and ST-segment changes during late morning. Three of the four patients had the characteristic clinical history of angina in early morning during usual activities but not during daytime activities despite the activities being more strenuous. Another 2 patients showed both exercise-induced ST-segment elevation and angina in early morning and afternoon, and they had the characteristic history of more episodes at night and in early morning but only occasionally in the daytime with or without relation to activity. One of the two patients showed intermittent ST-segment elevation during the exercise test. The other two patients had exercise-induced episodes neither in the early morning nor in the afternoon; they had a characteristic history of episodes only at night during sleep but never in the early morning nor in the daytime. Atropine did not suppress the exercise-induced angina in 4 of 5 patients studied. Doxazosin or phentolamine suppressed the exercise-induced episodes in 3 of 5 patients studied but aggravated spontaneous episodes in 3 patients. CONCLUSION: These data suggest that there's possibility of presence of different patterns of exercise-induced coronary spasm, which may be induced by different mechanisms from those in spontaneous episodes in patients with variant angina.
Atropine ; Constriction, Pathologic ; Coronary Vessels ; Depression ; Doxazosin ; Exercise Test ; Humans ; Phentolamine ; Spasm*

To evaluate the effect of time factor on the duplex flow measurements of the cavernosal artery we examined 30 patients with suspecting vasculogenic impotence by color flow duplex ultrasonographic evaluation. The cavernosal artery peak systolic flow velocity (PSV), end diastolic flow velocity ( EDV) and resistance index (RI) were determined bilaterally at preinjection, and 5, 10 and 15 min. following the intracavernosal injection(ICI) of PGEl(10ug) and phentolamine (0.2mg) mixture. We classified the patients based on the underlying vasculogenic status into normal (NL group; n=8), arteriogenic impotence with or without venogenic incompetency (AI group; n=11) and venogenic incompetency alone (VI group; n=11). The PSV in NL group was greatest at 5 min. postinjection (45.8+/-12.0cm/s) and declined significantly with time (30.0+/-5.8 cm/s) (p <0.06 ) and also significantly greater than the value obtained by the AI group at each time interval (p<0.01) with the greatest difference at 5 min. post injection. The EDV in NL group was low (0.75+/-0.96 cm/s) at preinjection and increased initially postinjection to 7.5+/-7.9 cm/s at 5 min. postinjection but then declined significantly (p<0.05). The EDV in VI group was significantly greater than that of NL at each time intervals (p<0.05) with the greatest value recorded at 10 min. post injection (l5.0 =5.5 cm/s). The RIs in all the group did not vary with time following ICI but that of NL was significantly lower than that of VI at each time intervals (p<0.01 ). Our data suggest that serial measurement of flow parameters, especially EDV as the indirect marker of veno-occlusive function, is necessary for the comprehensive understanding of hemodynamic vascular process of vasculogenic impotence since the duplex ultrasonographic flow parameters dynamically interact against time following ICI.
Arteries ; Erectile Dysfunction ; Female ; Hemodynamics ; Humans ; Impotence, Vasculogenic ; Male ; Phentolamine ; Time Factors ; Ultrasonography*

Intracavernous injection of prostaglandin E1 as a treatment for erectile dysfunction has achieved widespread acceptance due to low rates of drug induced priapism and penile fibrosis. We assessed the efficacy and side effects through our experience in a pharmacologic erection program using prostaglandin E1 only. A total of 79 impotent patients received a prostaglandin E1 monotherapy as a first-line pharmacological erection program for more than 2 months. Suspecting etiologies were non-vasculogenic non-neurogenic in 39, vasculogenic in 38 and neurogenic in 2 patients. The average duration using prostaglandin E1 was 4.6 months with a range of 2 to 14 months and the mean frequency of drug use was 4.9 per week. The average prostaglandin E1 dose used by patients in the program was 7.4Hg(0.37ml). No one had any side effects such as prolonged erection or fibrotic curvature. Dropout rate from prostaglandin E1 monotherapy after using for more than 2 months was 49%(39 patients) and reasons were penile pain in 7, drug expense in 4, inadequate response in 3, recovery of spontaneous erection in 2 and unclear in 23 patients. Among these dropout patients, 14 received Trimix(the mixture of 15mg of papaverine, 1. 25mg of phentolamine and 5ug of prostaglandin E1 per 1ml of solution) injection as a second- line pharmacological erection program with a good erectile response. We conclude that the prostaglandin E1 monotherapy represents a safe and efficacious method for the first-line selfinjection therapy.
Alprostadil* ; Erectile Dysfunction* ; Fibrosis ; Humans ; Male ; Papaverine ; Patient Dropouts ; Phentolamine ; Priapism