Putative cyclooxygenase-3 expression in rat brain cells.
Cyclooxygenase-3 (COX-3), a new acetaminophen-sensitive isoform of the COX family, has recently been cloned from canine tissues. Canine COX-3 apparently is identical to the full-length form of COX-1, with the exception that the COX-3 mRNA retains intron 1. Additionally, COX-3 mRNA expression is high in the brain. We investigated the expression of the putative rat COX-3 mRNA in primary cultures of neurons, astrocytes, endothelial cells, pericytes, and choroidal epithelial cells from the rat brain. Specific RT-PCR primers were designed to detect putative rat COX-3 mRNA, and the RT-PCR products were sequenced and compared to the known sequence of the rat COX-1 gene. Our results demonstrate that the mRNA of the putative COX-3 is expressed in all of the cell types except neurons. Cerebral endothelial cells showed the highest COX-3 expression. Whereas COX-2 expression increased several-fold after lipopolysaccharide (LPS) challenge, COX-1 and COX-3 expression did not change significantly, suggesting that cells constitutively express COX-3. In summary, we report, for the first time to our knowledge, that the putative COX-3 mRNA is detectable in rats and is differentially expressed in various cell types from rat brain, as well as that its expression is not stimulated by LPS.
Kis
Bela
B
Department of Physiology and Pharmacology, Wake Forest University, School of Medicine, Winston-Salem, NC 27157, USA. bkis@wfubmc.edu
Snipes
James A
JA
Isse
Toyohi
T
Nagy
Krisztina
K
Busija
David W
DW
D000818:Animals; D001253:Astrocytes / Q000201:enzymology; D002540:Cerebral Cortex / Q000166:cytology* / Q000201:enzymology; D002829:Choroid / Q000166:cytology / Q000201:enzymology; D004730:Endothelium, Vascular / Q000166:cytology / Q000201:enzymology; D004847:Epithelial Cells / Q000201:enzymology; D005333:Fetus; D009474:Neurons / Q000201:enzymology*; D020286:Pericytes / Q000201:enzymology; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014018:Tissue Distribution
D012333:RNA, Messenger; D011451:Prostaglandin-Endoperoxide Synthases; C466421:cyclooxygenase-3