title: Differential regulation of renin and Cox-2 expression in the renal cortex of C57Bl/6 mice.
abstract: Based on the controversy about the relevance of cyclooxygenase-2 (Cox-2)-derived prostanoids from the macula densa for the control of the renin system, this study aimed to determine the interrelation between Cox-2 and renin expression in the mouse kidney. In control mice renin mRNA was readily detectable whilst renocortical Cox-2 mRNA abundance was at the detection limit of the RNase protection assay and no specific signals for Cox-2 were obtained by in situ hybridization or Western blot analysis. Experimental maneuvers such as low-salt diet, treatment with loop diuretics or angiotensin I converting enzyme inhibitors clearly increased renin mRNA abundance up to sevenfold, but under none of these conditions renocortical Cox-2 mRNA levels were significantly changed. Moreover, the strong stimulation of renin expression by angiotensin I-converting enzyme inhibition was not changed by the cyclooxygenase inhibitor ibuprofen, which in turn clearly lowered tissue prostanoid content. Our data suggest a marked divergence of renin and Cox-2 expression in the kidney cortex of C57Bl/6 mice with no clear evidence for a role of Cox-2-derived prostanoids from the macula densa in the regulation of renin expression.
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D000818:Animals; D002034:Bumetanide / Q000494:pharmacology; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D004039:Diet, Sodium-Restricted; D004232:Diuretics / Q000494:pharmacology; D007052:Ibuprofen / Q000494:pharmacology; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D007672:Kidney Cortex / Q000378:metabolism*; D007679:Kidney Medulla / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D023282:Nuclease Protection Assays; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D017257:Ramipril / Q000494:pharmacology; D012083:Renin / Q000235:genetics / Q000378:metabolism*; D012260:Ribonucleases
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D004232:Diuretics; D007527:Isoenzymes; D012333:RNA, Messenger; D002034:Bumetanide; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; D012260:Ribonucleases; D012083:Renin; D017257:Ramipril; D007052:Ibuprofen