Korean J Urol.  2001 Nov;42(11):1211-1215.

Penile Cavernosal Smooth Muscle Fibrosis and TGF-beta1 Expression in Streptozotocin Induced Diabetic Rat

• Sohn KM
• Park K
• Ahn KY

Abstract

PURPOSE: The mechanism of corporal smooth muscle fibrosis in impotent patients with diabetes mellitus has not been well demonstrated. The aims of this study were to investigate the corpus cavernosal structure with histochemistry and the expression of TGF-beta1 with immunohistochemistry in the diabetic rat model.
MATERIALS AND METHODS
Fifteen male Sprague-Dawley rats (200-210g) were divided into two groups; control (n=8) and experimental group (n=7). The experimental group was received intravenous injection of streptozotocin (50mg/kg). After 4 weeks, blood sugar levels were measured, and penile tissue of rat was excised. Serial sections of the penis were used to perform Masson's trichrome stain, and immunohistochemistry for the TGF-beta1 expression.
RESULTS
The mean glucose concentrations were 67+/-11mg/dl (range; 50-85) in the control group and 408+/-105 mg/dl (range; 299-564) in the experimental group. Histology revealed diffuse corpus cavernosal fibrosis in the diabetic group. In histomorphometry, the percentage of corpus cavernosal smooth muscle in the diabetic group (9.9+/-1.5) significantly decreased compared with control group (15.0+/-4.0) (p=0.015). The immunoreactivity of TGF-beta1 in diabetic rats was prominent in the collagen connective tissue, fibroblasts, and smooth muscle fibers, whereas weak immunoactivity was detected in the corpus cavernosal structures of control rats.
CONCLUSIONS
Diabetes mellitus induces penile cavernosal tissue fibrosis with TGF-beta1 expression in the rat model. It implies that strategies to inhibit corpus cavernosal fibrosis is needed to prevent erectile dysfunction in diabetic patients.

Keyword

Diabetes mellitus; Transforming growth factor; Fibrosis; Impotence; Rat

MeSH Terms

Animals
Blood Glucose
Collagen
Connective Tissue
Diabetes Mellitus
Erectile Dysfunction
Fibroblasts
Fibrosis*
Glucose
Humans
Immunohistochemistry
Injections, Intravenous
Male
Models, Animal
Muscle, Smooth*
Penis
Rats*
Rats, Sprague-Dawley
Streptozocin*
Transforming Growth Factor beta1*
Transforming Growth Factors
Blood Glucose
Collagen
Glucose
Streptozocin
Transforming Growth Factor beta1
Transforming Growth Factors