Differential expression of two alpha 2-adrenergic receptor subtype mRNAs in human tissues

Brain Res Mol Brain Res. 1992 Nov;16(1-2):57-63. doi: 10.1016/0169-328x(92)90193-f.


Genetic subtypes of alpha 2-adrenergic receptors (AR) may mediate distinct physiological functions, and undergo differential cell type-specific regulation. Thus, these distinct receptor subtypes are possible targets for the development of subtype-selective drugs. We have analyzed the tissue distribution of two human alpha 2-adrenoceptor subtype gene mRNAs, alpha 2-C4 and alpha 2-C10, in normal human fetal and adult tissues. Both receptor subtype mRNAs were abundantly expressed in fetal brain and choroid plexus. In non-neural fetal tissues, alpha 2-C10 mRNA was detected in spleen, kidney, adrenal gland, and skin, while alpha 2-C4 transcripts were observed only in kidney and skin. Most regions of the adult brain also expressed both subtypes, but with marked quantitative differences. For example, cerebral cortex contained predominantly alpha 2-C10 mRNA, whereas the caudate nucleus expressed mostly alpha 2-C4 mRNA. In adult peripheral tissues, alpha 2-C10 mRNA expression was most abundant in spleen and renal cortex, and expression of alpha 2-C4 mRNA was strongest in renal cortex and medulla. These different expression patterns provide evidence for the differential regulation of the two alpha 2-adrenergic receptor genes and warrant further investigation with techniques capable of improved anatomical resolution. Regional differences in receptor subtype expression may be valuable for the development of new, subtype-selective pharmacological agents with more targeted actions compared to currently used alpha 2-adrenoceptor agonists and antagonists.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain / embryology
  • Brain / metabolism*
  • Cell Line
  • Humans
  • Nucleic Acid Hybridization
  • Organ Specificity / physiology
  • RNA Probes
  • RNA, Antisense / genetics
  • RNA, Messenger / biosynthesis*
  • Receptors, Adrenergic, alpha / genetics*
  • Ribonucleases
  • Viscera / embryology
  • Viscera / metabolism*


  • RNA Probes
  • RNA, Antisense
  • RNA, Messenger
  • Receptors, Adrenergic, alpha
  • Ribonucleases