Relaxation of rabbit cavernous smooth muscle to 17beta-estradiol: a non-genomic, NO-independent mechanism.
- Author:
Sae-Chul KIM
1
;
Kyung-Kun SEO
;
Soon-Chul MYUNG
;
Moo Yeol LEE
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Dactinomycin; pharmacology; Dose-Response Relationship, Drug; Electrophysiology; Enzyme Inhibitors; pharmacology; Estradiol; pharmacology; In Vitro Techniques; Indicators and Reagents; Male; Membrane Potentials; drug effects; Muscle Relaxation; drug effects; Muscle, Smooth; drug effects; NG-Nitroarginine Methyl Ester; pharmacology; Nitric Oxide Synthase; antagonists & inhibitors; Nitric Oxide Synthase Type III; Norepinephrine; pharmacology; Patch-Clamp Techniques; Penis; drug effects; Peptides; pharmacology; Potassium Channel Blockers; pharmacology; Rabbits; Vasoconstrictor Agents; pharmacology
- From: Asian Journal of Andrology 2004;6(2):127-131
- CountryChina
- Language:English
-
Abstract:
AIMTo investigate whether estrogen was involved in relaxation of rabbit cavernous smooth muscle.
METHODSRelaxation response of the rabbit cavernous smooth muscles to 17beta-estradiol (0.3, 3, 30 and 300 nmol/L) were observed in vitro. The response of the muscle strips to estrogen after incubation with either actinomycin D (10 micromol/L) or L-NAME (10 micromol/L) were also evaluated. Inside-out mode of patch clamp in a single smooth muscle cell was applied to investigate the Maxi-K channel activities.
RESULTSEstrogen caused a dose-dependent relaxation of the strips precontracted with norepinephrine. The maximal response was noted about 10 minutes after treatment. The estrogen-induced relaxation was prevented by neither actinomycin D nor L-NAME, suggesting that the response was not mediated by gene transcription or nitric oxide (NO). Application of 17beta-estradiol increased the Maxi-K channel activities.
CONCLUSION17beta-estradiol may be involved in relaxation of rabbit cavernous smooth muscles via a non-genomic and NO independent mechanism. 17beta-estradiol stimulates Maxi-K channel of the rabbit cavernous myocyte.
