Positive effect of prostaglandin on regulation of prostatic blood flow.
OBJECTIVE
To investigate the effects of prostaglandin E2 (PGE2) and its antireceptor antibody on prostatic blood flow regulation using a rat model. We estimated that PGE2 participated in the signaling pathway of hormonal regulation of the prostatic blood flow.


METHODS
The rats were castrated and injected locally with dihydrotestosterone (200 ng/head) or PGE2 (250 ng/head) directly into the prostatic membrane. After local dihydrotestosterone or PGE2 administration, anti-PGE2 receptor antibody (200 ng/head) was injected locally to investigate interruption of the signaling pathway. After administration, we evaluated the relative prostatic blood flow using a laser blood flow meter. The change in cyclooxgenase-2 mRNA expression and the changes in PGE2 concentration in response to androgen stimulation were also examined.


RESULTS
PGE2 was involved in blood flow regulation with activity equal to that of androgen. The effect of dihydrotestosterone was abolished by coadministration with anti-PGE2 receptor antibody. Cyclooxgenase-2 gene expression was upregulated in response to androgen stimulation. The PGE2 concentration also increased in response to androgen stimulation.


CONCLUSIONS
Our finding of PGE2 participation in androgen regulation of prostatic blood flow might lead to pathophysiologic elucidation of prostatic diseases.
Kashiwagi
Bunzo
B
Department of Urology, Gunma University Graduate School of Medicine, Maebashi, Japan. bkashiwa@med.gunma-u.ac.jp
Shibata
Yasuhiro
Y
Ohki
Kazunari
K
Arai
Seiji
S
Honma
Seijiro
S
Suzuki
Kazuhiro
K
D000818:Animals; D015232:Dinoprostone / Q000502:physiology*; D008297:Male; D011467:Prostate / Q000098:blood supply*; D051381:Rats; D017208:Rats, Wistar; D012039:Regional Blood Flow
D015232:Dinoprostone