title: Effects of moxonidine and metoprolol in penile circulation in hypertensive men with erectile dysfunction: results of a pilot study.
abstract: Centrally acting (moxonidine) and peripherally acting (metoprolol) sympatholytic agents might have different actions upon penile circulation in hypertensive men with erectile dysfunction. A total of 11 nonsmoking, hypertensive but otherwise healthy men with erectile dysfunction were studied after 8 weeks on moxonidine monotherapy (0.4 mg per day, increased to 0.6 mg if needed) and then after 8 weeks of metoprolol monotherapy (100 mg per day, increased to 200 mg if needed) in a crossover design. At the end of each treatment phase, the subjects were asked about their subjective erectile capacity (nocturnal and coital erections), and resting and stimulated (after intracavernosal injection of a mixture of alprostadil and phentolamine) penile deep artery diameters and systolic peak velocities were measured by color Doppler ultrasonography. There were no significant differences in blood pressure after either therapy. The change from earlier antihypertensive therapy, moxonidine produced significant subjective amelioration of sexual dysfunction in 9/11 of the men (< or = 0.001), whereas 9/11 returned to impaired dysfunction after crossover to metoprolol treatment. Resting and stimulated deep penile diameters and peak systolic velocities were higher after moxonidine treatment compared with metoprolol (diameters: < or = 0.004, < or = 0.0001; velocities: < or = 0.008, < or = 0.038). The centrally acting sympatholytic agent moxonidine seems to improve erectile function both subjectively and objectively and has a better effect on penile circulation compared with the peripherally acting sympatholytic agent metoprolol.
authors.affiliation: Mehilainen Co, Erectile Dysfunction Clinic, Turku, Finland. juhana.piha@pp.fimnet.fi
authors.forename: J
authors.initials: J
authors.lastname: Piha
authors.forename: R
authors.initials: R
authors.lastname: Kaaja
mesh_terms: D000328:Adult; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001158:Arteries; D001783:Blood Flow Velocity / Q000187:drug effects; D018592:Cross-Over Studies; D004334:Drug Administration Schedule; D007172:Erectile Dysfunction / Q000188:drug therapy* / Q000209:etiology*; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000188:drug therapy; D007093:Imidazoles / Q000008:administration & dosage*; D008297:Male; D008790:Metoprolol / Q000008:administration & dosage*; D008875:Middle Aged; D010413:Penis / Q000098:blood supply* / Q000000981:diagnostic imaging; D010865:Pilot Projects; D012039:Regional Blood Flow / Q000187:drug effects; D013565:Sympatholytics / Q000008:administration & dosage*; D018608:Ultrasonography, Doppler
chemical_list: D000959:Antihypertensive Agents; D007093:Imidazoles; D013565:Sympatholytics; C043482:moxonidine; D008790:Metoprolol