Korean J Androl.  2004 Aug;22(2):75-80.

Increased Expression of Hypoxia-Inducible Factor-1alpha in Castrated Rat Penile Tissue

• Yang DY
• Lee WK
• Kim KW
• Seo CD
• Lee YG
• Kim H
• Kim SY
• Park HW
• Cho SJ

Abstract

PURPOSE
Hypoxia-inducible factor 1(HIF-1) is a transcriptional activator of genes whose products are involved in systemic, local, and cellular responses to hypoxia. We investigated the effect of androgen deprivation on the expression of HIF-1alpha and related proteins in the penile corpus cavernosum of castrated rat.
MATERIALS AND METHODS
Thirty adult male Sprague-Dawley rats(250~350 gm) were divided into 3 groups of 10 each: sham operation(group 1), bilateral orchiectomy(group 2), and bilateral orchiectomy plus hormone replacement(group 3). Testosterone propionate(2 mg/day for 4 weeks) was used for hormone replacement. At 4 weeks after surgery, serum testosterone and erythropoietin were measured, and the expression of HIF-1alpha and VEGF were examined by immunohistochemical staining and Western blot of corpus cavernosum.
RESULTS
There was no significant change in serum erythropoietin among the three groups. HIF-1alpha and VEGF immuno-positive cells were dense in vascular endothelium and cavernosal smooth muscle and showed more intense staining in the orchiectomy group compared with the control and sham operation groups. The amount of HIF-1alpha and VEGF proteins detected by Western blot were also increased in the orchiectomy group compared with the control and sham operation groups.
CONCLUSIONS
These results suggest that increased HIF-1alpha expression in the penile tissue of castrated rat results from adaptive responses to hypoxia, and testosterone deprivation may contribute to hypoxic injury in the cavernosal microenvironment.

Keyword

Hypogonadism; Hypoxia-inducible factor 1; Vascular endothelial growth factor; Erectile dysfunction

MeSH Terms

Adult
Animals
Anoxia
Blotting, Western
Endothelium, Vascular
Erectile Dysfunction
Erythropoietin
Humans
Hypogonadism
Hypoxia-Inducible Factor 1
Male
Muscle, Smooth
Orchiectomy
Rats*
Rats, Sprague-Dawley
Testosterone
Vascular Endothelial Growth Factor A
Erythropoietin
Hypoxia-Inducible Factor 1
Testosterone
Vascular Endothelial Growth Factor A