RT Journal Article
SR Electronic
T1 Evaluation of Urothelial Stretch-Induced Cyclooxygenase-2 Expression in Novel Human Cell Culture and Porcine in Vivo Ureteral Obstruction Models
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 965
OP 972
DO 10.1124/jpet.105.099184
VO 317
IS 3
A1 Travis J. Jerde
A1 William S. Mellon
A1 Dale E. Bjorling
A1 Stephen Y. Nakada
YR 2006
UL http://jpet.aspetjournals.org/content/317/3/965.abstract
AB Obstruction and stretch induce cyclooxygenase (COX)-2 expression and prostanoid synthesis in urinary tissues, causing pain, inflammation, hypercontractility, and cell proliferation. Our objective was to characterize acute COX-2 induction during in vivo ureteral obstruction, establish a cell culture model of urothelial stretch-induced COX-2 expression, and evaluate whether mechanotransduction could alter transcriptional and post-transcriptional regulation of COX-2. We performed laparoscopic unilateral ureteral ligation in pigs and allowed progression for 1, 2, 6, 24, or 48 h. We evaluated COX-2 expression with reverse transcriptase (RT)-polymerase chain reaction (PCR) and immunoblotting. We cultured primary human urothelial cells on stretch plates, applied stretch for up to 48 h, and measured COX-2 expression by RT-PCR and immunoblotting, transcription with run-on assays, and mRNA stability with actinomycin mRNA decay assays. In vivo ureteral obstruction induced COX-2 expression 4-fold within 6 h, maintaining induction for 24 h. In cell culture, stretch induced COX-2 steady-state mRNA and protein within the first 3 h of stretch, maintaining this induction for over 6 h. Three hours of stretch doubled COX-2 transcription relative to unstretched controls and increased COX-2 mRNA half-life 3-fold. This is the first report to characterize in vivo temporal stretch-induced COX-2 expression in the urothelium and establish a primary urothelial cell culture model for the study of stretch-induced COX-2 mechanisms. This is also the first report to identify alterations in steady-state COX-2 mRNA having components of both transcriptional and post-transcriptional regulation of stretch-regulated COX-2. Future elucidation of COX-2 signaling may identify novel therapeutic targets for treating stretch and distension of urinary tissues. The American Society for Pharmacology and Experimental Therapeutics