Smooth muscle pathology and XXXX .

@entity1 @entity323 @entity82 @entity251 @entity63 @entity146 @entity384 @entity26 @entity235 @entity95 @entity5015 @entity842 @entity342 @entity35 @entity731 @entity2057
Penile erection is a vascular phenomenon that results from smooth muscle relaxation, @entity384 and venous restriction. The @entity731 of the penis that occurs with aging causes a decrease in penile @entity26 tension. A reduction of smooth muscle cells has been demonstrated in relation with this change in @entity26 tension. Changes in the ratio of penile collagen have also been observed and could explain the decrease in penile elasticity and compliance. @entity63 is, therefore, associated with @entity82 but also with @entity842 (NO)-cyclic guanosine monophosphate. The sensitivity of the alpha-adrenoceptors on the smooth muscle cells increases with aging. All those modifications can explain the prevalence of @entity323 with aging. Low @entity26 tension in prostanoid production may also play a role in the mechanism of @entity63 -induced cavernosal @entity82 ; however, intracavernous injections of @entity5015 do not seem to modify the intracavernous structures by reducing @entity2057 . The effects of @entity342 on libido and @entity146 are well established, but their role in the @entity1 erectile mechanism remains unclear. Several studies performed on animals have demonstrated impacts directly on both the physiological function and the trabecular structure of the corpora cavernosa in @entity35 , @entity235 and @entity95 . However, in @entity1 , no study seems to demonstrate a role of @entity251 on @entity2057 or penile neurologic control. @entity251 treatment alters the @entity1 behavior but not penile physiologic processes. Further studies are necessary to explain the real role of @entity251 not only on the peripheral mechanism of erection but also on the central control.
