Quantitation of proenkephalin A messenger RNA in bovine brain, pituitary and adrenal medulla: correlation between mRNA and peptide levels.
Concentrations of mRNA coding for the opioid peptide precursor proenkephalin A were measured in bovine brain areas, pituitary and adrenal medulla. In all tissues, a single hybridizable species of 1400 bases in size was found by Northern blot analysis using as a probe a single-stranded (ss) cDNA complementary to bovine proenkephalin A mRNA. In solution hybridization experiments the distribution of the mRNA was quantified. Considerable differences were found for the abundance of proenkephalin A mRNA in the various tissues: from 0.023% in the adrenal medulla to 0.00002% in the adenohypophysis. Relative abundance in the various brain areas varied greater than 20-fold, being highest in the caudate nucleus (0.0025%) and lowest in the thalamus and substantia nigra (0.0001%). Comparison with immunoreactive peptide concentrations in these tissues showed a close correlation between the levels of proenkephalin A mRNA and the immunoreactive peptides.
D000313:Adrenal Medulla / Q000032:analysis*; D000818:Animals; D001923:Brain Chemistry; D002417:Cattle; D004745:Enkephalins / Q000032:analysis / Q000235:genetics*; D010902:Pituitary Gland / Q000032:analysis*; D011498:Protein Precursors / Q000032:analysis / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis*
D004745:Enkephalins; D011498:Protein Precursors; D012333:RNA, Messenger; C029992:proenkephalin