Immunohistochemical description of cyclic nucleotide phosphodiesterase (PDE) isoenzymes in the human labia minora.
BACKGROUND
Up until now, only minimal research has been carried out on those female genital organs known to contribute to the normal cycle of sexual arousal and orgasm. Some findings indicated that there might be a significance of cyclic nucleotide-mediated pathways in the control of the normal function of female genital tissues.


OBJECTIVE
To elucidate, by means of immunohistochemistry, the distribution of the phosphodiesterase (PDE) isoenzymes 1, 3, 4, 5, 10, and 11 in the human labia minora.


METHODS
The amount of immunohistochemical staining specific for cyclic adenosine monophosphate (cAMP)- and/or cyclic guanosine monophosphate (cGMP)-degrading PDE isoenzymes was detected.


METHODS
Human labial tissue was obtained from four female cadavers (age at death: 18-42 years). Vibratome sections prepared from formaldehyde-fixated tissue specimens were incubated with primary antibodies directed against the respective PDE isoenzymes. Sections were then incubated with fluorochrome (fluorescein isothiocyanate, Texas Red)-labeled secondary antibodies. Visualization was commenced by means of a laser fluorescence microscope.


RESULTS
Immunostaining indicating the expression of PDE4 and PDE5 was abundantly observed in the smooth musculature of vessels interspersing the tissue. Immunoreactions specific for PDE3 were recognized in epithelial and subepithelial layers, sebaceous glands, and interstitial or neuroendocrine-like single cells located in the epithelium. Signals related to PDE10 and PDE11 were limited to the epithelium or glandular-like structures, respectively.


CONCLUSIONS
Our results, for the first time, demonstrate the presence of cAMP- and cGMP-PDE isoenzymes in the human labia minora and give a hint to a significance of PDE4 and PDE5 in the control of labial vascular tissue function.
Ückert
Stefan
S
Hannover Medical School-Department of Urology, Hannover, Germany;; IPF PharmaCeuticals GmbH-Urological Research Unit, Hannover, Germany;. Electronic address: streetgang@gmx.de.
Oelke
Matthias
M
University of Amsterdam, Academic Medical Center-Department of Urology, Amsterdam, The Netherlands.
Albrecht
Knut
K
Hannover Medical School-Department of Urology, Hannover, Germany.
Stief
Christian
C
Ludwig-Maximilians-University, Academic Hospital Grosshadern-Department of Urology, Munich, Germany.
Jonas
Udo
U
Hannover Medical School-Department of Urology, Hannover, Germany.
Hedlund
Petter
P
Lund University Hospital-Department of Clinical & Experimental Pharmacology, Lund, Sweden.
D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000032:analysis*; D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000032:analysis*; D000328:Adult; D001143:Arousal / Q000502:physiology*; D002102:Cadaver; D000242:Cyclic AMP / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism; D054684:Cyclic Nucleotide Phosphodiesterases, Type 3; D054703:Cyclic Nucleotide Phosphodiesterases, Type 4; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007527:Isoenzymes / Q000032:analysis; D014844:Vulva / Q000201:enzymology*
D007527:Isoenzymes; D000242:Cyclic AMP; D015105:3',5'-Cyclic-AMP Phosphodiesterases; D054684:Cyclic Nucleotide Phosphodiesterases, Type 3; D054703:Cyclic Nucleotide Phosphodiesterases, Type 4; D015106:3',5'-Cyclic-GMP Phosphodiesterases; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; C517381:PDE5A protein, human; D006152:Cyclic GMP