Lobe-specific expression of phosphodiesterase 5 in rat prostate.
OBJECTIVE
To investigate the level and location of phosphodiesterase 5 (PDE5) expression in rat prostate.


METHODS
The ventral, dorsal, and lateral lobes of rat prostate were examined for PDE5 expression by Western blotting. Intact rat urogenital complex, including the urinary bladder and accessory reproductive glands, was examined for PDE5 expression by immunohistochemistry. Individual prostatic lobes were further examined by immunofluorescence for expression of PDE5, α-smooth muscle actin, and rat endothelial cell antigen.


RESULTS
Western blot analysis showed that PDE5 was expressed at a significantly lower level in dorsal lobe (DL) than in ventral lobe (VL) or lateral lobe (LL). Immunohistochemistry and immunofluorescence analyses showed that PDE5 was expressed in both acinar epithelium and periacinar smooth muscle. However, although similar levels of smooth muscle PDE5 expression were observed in all 3 prostatic lobes, significantly lower level of epithelial PDE5 expression was found in DL compared with VL or LL. In prostatic blood vessels, PDE5 expression was clearly visible in the endothelium but not as easily detectable in the smooth muscle.


CONCLUSIONS
PDE5 was expressed in the acinar epithelium and periacinar smooth muscle of rat prostate. However, the epithelial PDE5 expression was significantly less in DL than in VL or LL. Regardless, the acinar wall, not the blood vessel wall, is the predominant PDE5 expression site in rat prostate.
Knuppe Molecular Urology Laboratory, Department of Urology, University of California, San Francisco, CA; Molecular Biology Laboratory, Andrology Center, Peking University First Hospital, Peking University, Beijing, China.
Lin
L
Wang
Knuppe Molecular Urology Laboratory, Department of Urology, University of California, San Francisco, CA; Department of Urology, Peking University First Hospital and the Institute of Urology, Peking University, Beijing, China.
Xiaoyu
X
Zhang
Knuppe Molecular Urology Laboratory, Department of Urology, University of California, San Francisco, CA.
Guifang
G
Wang
Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, India.
Sandhya S
SS
Visweswariah
Knuppe Molecular Urology Laboratory, Department of Urology, University of California, San Francisco, CA.
Guiting
G
Lin
Molecular Biology Laboratory, Andrology Center, Peking University First Hospital, Peking University, Beijing, China.
Zhongcheng
Z
Xin
Knuppe Molecular Urology Laboratory, Department of Urology, University of California, San Francisco, CA.
Tom F
TF
Lue
Knuppe Molecular Urology Laboratory, Department of Urology, University of California, San Francisco, CA. Electronic address: clin@urology.ucsf.edu.
Ching-Shwun
CS
Lin
D000818:Animals; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5 / Q000096:biosynthesis*; D008297:Male; D011467:Prostate / Q000033:anatomy & histology / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D054706:Cyclic Nucleotide Phosphodiesterases, Type 5