Testosterone induces vascular endothelial growth factor synthesis in the ventral prostate in castrated rats.
OBJECTIVE
Recent studies suggest that the vasculature is important for the control of prostate growth. Castration induces an involution of the prostate gland and its vasculature. Replacement of testosterone stimulates endothelial cell proliferation and normalizes vascular volumes and blood flow several days before organ regrowth. Antiangiogenesis treatment inhibits the growth of prostate tumors. Understanding the regulation of the prostate vasculature may therefore provide important knowledge of the mechanisms responsible for the growth of non-malignant and malignant prostate tissue. Castration induced regression and testosterone stimulated regrowth of the prostatic vasculature have here been used to study the involvement of the angiogenic factor vascular endothelial growth factor (VEGF) and its receptors flt-1 and flk-1/KDR in the regulation of the prostatic vasculature.


METHODS
VEGF, flt-1, and flk-1/KDR levels were quantified in the rat ventral prostate following castration and testosterone replacement. Methods used were competitive RT-PCR, Western blot and immunohistochemistry.


RESULTS
VEGF mRNA and protein levels were significantly decreased by castration and testosterone treatment induced VEGF synthesis in the rat ventral prostate epithelium. Flt-1 and flk-1/KDR receptor levels were unaffected by castration and testosterone treatment.


CONCLUSIONS
Castration down regulates VEGF and testosterone induces VEGF synthesis in epithelial cells in the rat ventral prostate.
Häggström
S
S
Department of Urology & Andrology, Umeå University, Sweden.
Lissbrant
I F
IF
Bergh
A
A
Damber
J E
JE
D000818:Animals; D016228:Endothelial Growth Factors / Q000096:biosynthesis*; D008222:Lymphokines / Q000096:biosynthesis*; D008297:Male; D009919:Orchiectomy; D011467:Prostate / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020794:Receptor Protein-Tyrosine Kinases / Q000096:biosynthesis; D017978:Receptors, Growth Factor / Q000096:biosynthesis; D011975:Receptors, Mitogen / Q000096:biosynthesis; D040262:Receptors, Vascular Endothelial Growth Factor; D013739:Testosterone / Q000494:pharmacology / Q000502:physiology*; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016228:Endothelial Growth Factors; D008222:Lymphokines; D017978:Receptors, Growth Factor; D011975:Receptors, Mitogen; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D013739:Testosterone; D020794:Receptor Protein-Tyrosine Kinases; D040262:Receptors, Vascular Endothelial Growth Factor