Effect of hypercapnia and hypocapnia on tryptophan and tyrosine hydroxylation in rat brain

Acta Physiol Scand. 1977 Apr;99(4):503-9. doi: 10.1111/j.1748-1716.1977.tb10404.x.

Abstract

The effects of induced hypo- and hypercapnia upon the rate of hydroxylation of tryptophan and tyrosine in the rat brain were studied by measuring the accumulation of 5-HTP and DOPA following administration of the aromatic L-aminoacid decarboxylase inhibitor 3-hydroxybenzylhydrazine HCl (NSD 1015). The results suggest that the hydroxylation of tryptophan varies directly with the tissue Po2. On the other hand, the hydroxylation of tyrosine did not show a simple relationship to Po2 but appeared to be influenced by pH changes.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 5-Hydroxytryptophan / metabolism
  • Amino Acids / metabolism
  • Ammonia / metabolism
  • Animals
  • Brain / metabolism*
  • Carbohydrate Metabolism
  • Carbon Dioxide / blood*
  • Dihydroxyphenylalanine / metabolism
  • Hydrazines / pharmacology
  • Hydrogen-Ion Concentration
  • Hydroxylation
  • Hypercapnia / metabolism*
  • Male
  • Partial Pressure
  • Phosphates / metabolism
  • Rats
  • Rats, Inbred Strains
  • Tryptophan / metabolism*
  • Tyrosine / metabolism*

Substances

  • Amino Acids
  • Hydrazines
  • Phosphates
  • Carbon Dioxide
  • Tyrosine
  • Dihydroxyphenylalanine
  • Ammonia
  • Tryptophan
  • 5-Hydroxytryptophan