Regional heterogeneity in expression of the sphingosine-1-phosphate pathway in the female rat lower urinary tract.
OBJECTIVE
We investigated the existence and regional distribution of sphingosine-1-phosphate regulatory enzymes and receptors in the lower urinary tract and determined the functional role of sphingosine-1-phosphate receptors in the bladder.


METHODS
Lower urinary tract tissue from 10 female rats was harvested for real-time reverse transcriptase-polymerase chain reaction or organ bath physiology, whereas blood serum was obtained for high-performance liquid chromatography determination of sphingosine-1-phosphate levels. Statistical analysis included the Student t test and analysis of variance.


RESULTS
All 3 sphingosine-1-phosphate receptors and major enzymes were expressed throughout the lower urinary tract, but expression and physiologic force generation varied among regions. Sphingosine-1-phosphate was detected in serum.


CONCLUSIONS
We provide novel data that the sphingosine-1-phosphate signaling pathway regulatory proteins exist throughout the female rat lower urinary tract, but that relative expression exhibits regional heterogeneity corresponding with lower urinary tract contractile response to sphingosine-1-phosphate. Our study suggests that sphingosine-1-phosphate signaling is important in the lower urinary tract and identifies this pathway as a possible target for altering bladder smooth muscle tone.
Sandhu
Katherine S
KS
Division of Female Pelvic Medicine and Reconstructive Surgery, Department of Obstetrics, Gynecology, and Urology, Albert Einstein College of Medicine, Bronx, NY 10461, USA. kathysandhu@gmail.com
Chua
Rowena G
RG
Zhang
Xinhua
X
Kanika
Nirmala Devi
ND
Collins
Sarah A
SA
Mikhail
Magdy
M
Melman
Arnold
A
Disanto
Michael E
ME
D000818:Animals; D004798:Enzymes / Q000235:genetics* / Q000378:metabolism; D005260:Female; D018740:Genetic Heterogeneity; D008190:Lyases / Q000235:genetics / Q000378:metabolism; D008246:Lysophospholipids / Q000097:blood*; D009119:Muscle Contraction / Q000502:physiology; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D049349:Receptors, Lysosphingolipid / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology*; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000097:blood; D014521:Urethra / Q000502:physiology; D001743:Urinary Bladder / Q000502:physiology*; D053201:Urinary Bladder, Overactive / Q000378:metabolism / Q000503:physiopathology; D054460:rho-Associated Kinases / Q000235:genetics / Q000378:metabolism; D000099157:Sphingosine Kinase
D004798:Enzymes; D008190:Lyases; D008246:Lysophospholipids; D017853:Phosphotransferases (Alcohol Group Acceptor); D049349:Receptors, Lysosphingolipid; D013110:Sphingosine; D054460:rho-Associated Kinases; D000099157:Sphingosine Kinase; C060506:sphingosine 1-phosphate