Expression of mRNA for cyclooxygenase-1 and cyclooxygenase-2 in human tissues

FEBS Lett. 1993 Sep 13;330(2):156-60. doi: 10.1016/0014-5793(93)80263-t.


The rate-limiting step in the formation of prostanoids is the conversion of arachidonic acid to prostaglandin H2 by cyclooxygenase, also known as prostaglandin G/H synthase/cyclooxygenase. Two forms of cyclooxygenase have been characterized: a ubiquitously expressed form (COX-1) and a recently described second form (COX-2) inducible by various factors including mitogens, hormones, serum and cytokines. Here we quantitate by the reverse transcriptase-polymerase chain reaction (RT-PCR) the expression of COX-1 and COX-2 mRNA in human tissues including lung, uterus, testis, brain, pancreas, kidney, liver, thymus, prostate, mammary gland, stomach and small intestine. All tissues examined contained both COX-1 and COX-2 mRNA and could be grouped according to the level of COX mRNA expression. The highest levels of COX mRNAs were detected in the prostate where approximately equal levels of COX-1 and COX-2 transcripts were present. In the lung high levels of COX-2 were observed whereas COX-1 mRNA levels were about 2-fold lower. An intermediate level of expression of both COX-1 and COX-2 mRNA was observed in the mammary gland, stomach, small intestine, and uterus. The lowest levels of COX-1 and COX-2 mRNA were observed in the testis, pancreas, kidney, liver, thymus, and brain.

MeSH terms

  • Base Sequence
  • Blotting, Northern
  • Blotting, Southern
  • DNA
  • Glyceraldehyde-3-Phosphate Dehydrogenases / genetics
  • Humans
  • Isoenzymes / genetics*
  • Molecular Sequence Data
  • Polymerase Chain Reaction
  • Prostaglandin-Endoperoxide Synthases / genetics*
  • RNA, Messenger / metabolism*


  • Isoenzymes
  • RNA, Messenger
  • DNA
  • Prostaglandin-Endoperoxide Synthases
  • Glyceraldehyde-3-Phosphate Dehydrogenases