An animal model of Peyronie's-like condition associated with an increase of transforming growth factor beta mRNA and protein expression.
OBJECTIVE
Transforming growth factor beta (TGF-beta) is involved in numerous vital processes including tissue fibrosis. Our objective was to study the role of TGF-beta in the induction of a Peyronie's-like condition and to produce an animal model for the further study of Peyronie's disease.


METHODS
Twenty-four adult male Sprague-Dawley rats were divided into two groups. Different concentrations of cytomodulin, a synthetic heptopeptide with TGF-beta-like activity, were injected into the tunica of each rat from the first group (n = 18). Rats in the second group (n = 6) received saline injections as a control. The tunical tissues were taken after 3 days, 2 weeks, and 6 weeks and were examined using Hart and Trichrome stains. In the same tissue samples, TGF-beta mRNA and protein expression were studied.


RESULTS
Histological alterations were observed in 15 out of 18 cytomodulin-injected rats, especially in tissue examined after 6 weeks. The most prominent changes were chronic cellular infiltration, focal and diffuse elastosis, thickening, disorganization and clumping of the collagen bundles. Results from immunoblot revealed remarkable TGF-beta1 protein expression in all the cytomodulin-injected rats only after 2 and 6 weeks. No remarkable TGF-beta2 or TGF-beta3 protein expression was observed. TGF-beta1 mRNA expression in the cytomodulin-injected rats was noticed in rats injected with higher concentrations after 3 days, while it was expressed in all rats after 2 weeks. There was no expression in the control group after either 3 days or 2 weeks.


CONCLUSIONS
Cytomodulin can induce Peyronie's-like condition in the rat penis, which may explain the role of TGF-beta in the pathogenesis of Peyronie's disease.
El-Sakka
A I
AI
Department of Urology, University of California School of Medicine, San Francisco 94143-0738, USA.
Hassoba
H M
HM
Chui
R M
RM
Bhatnagar
R S
RS
Dahiya
R
R
Lue
T F
TF
D000818:Animals; D004195:Disease Models, Animal; D015870:Gene Expression; D008297:Male; D010411:Penile Induration / Q000378:metabolism*; D010413:Penis / Q000737:chemistry; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D016212:Transforming Growth Factor beta / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics
D012333:RNA, Messenger; D016212:Transforming Growth Factor beta