Quelle:
Medline Abstract
Rauchen
und Impotenz: das Rauchen von Zigaretten erhöht das Risiko
für eine erektile Dysfunktion (Impotenz). Bisher ist allerdings
nicht bekannt welche Einzel-Komponente des Zigarettenrauchs die
erektile Dysfunktion direkt auslöst. Ebenso wenig sind die Mechanismen
bekannt, die durch den Zigarettenrauch negativ beeinflusst werden
und schließlich die Ausbildung einer Erektion erleichtern. Bekannt
ist lediglich, dass das Rauchen von Zigaretten die Bioverfügbarkeit
von
Stickstoffmonoxid im Blut vermindert. Gleichzeitig erhöht
sich die Menge freier Sauerstoff-Radikale. Offenbar begünstigt
diese Kombination von gleichzeitig ablaufenden Stoffwechsel-Vorgängen
durch die Beeinflussung der Blutgefäß-Funktionen die Entstehung
einer erektilen Dysfunktion.
Die
vollständige englischsprachige Kurzversion dieser Studie
(sog. MEDLINE Abstract) finden Sie
hier
J
Sex Med. 2008 Mar 4 [Epub ahead of print]
Cigarette Smoking and Erectile Dysfunction: Focus on NO Bioavailability
and ROS Generation.
Tostes RC, Carneiro FS, Lee AJ, Giachini FR, Leite R, Osawa Y,
Webb RC.
University of Sao Paulo, Department of Pharmacology, Sao Paulo,
SP, Brazil.
Introduction. Thirty million men in the United States suffer
from erectile dysfunction (ED) and this number is expected to
double by 2025. Considered a major public health problem, which
seriously affects the quality of life of patients and their partners,
ED becomes increasingly prevalent with age and chronic smoking
is a major risk factor in the development of ED. Aim. To review
available evidence concerning the effects of cigarette smoking
on vascular changes associated with decreased nitric oxide (NO)
bioavailability and increased reactive oxygen species (ROS) generation.
Methods.
We examined epidemiological and clinical data linking cigarette
smoking and ED, and the effects of smoking on vascular NO bioavailability
and ROS generation.
Main
Outcome Measures. There are strong parallels
between smoking and ED and considerable evidence supporting
the concept that smoking-related ED is associated with reduced
bioavailability of NO because of increased ROS.
Results.
Cigarette smoking-induced ED in human and animal models is associated
with impaired arterial flow to the penis or acute vasospasm of
the penile arteries. Long-term smoking produces detrimental effects
on the vascular endothelium and peripheral nerves and also causes
ultrastructural damage to the corporal tissue, all considered
to play a role in chronic smoking-induced ED. Clinical and basic
science studies provide strong indirect evidence that smoking
may affect penile erection by the impairment of endothelium-dependent
smooth muscle relaxation or more specifically by affecting NO
production via increased ROS generation. Whether nicotine or other
products of cigarette smoke mediate all effects related to vascular
damage is still unknown.
Conclusions.
Smoking prevention represents an important approach for reducing
the risk of ED. The characterization of the components of cigarette
smoke leading to ED and the mechanisms by which these components
alter signaling pathways activated in erectile responses are necessary
for a complete comprehension of cigarette smoking-associated ED.
PMID: 18331273 [PubMed - as supplied by publisher]
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