Tyrosine Increases Blood Pressure in Hypotensive Rats

Abstract

Administration of tyrosine, the amino acid precursor of catecholamines, increased blood pressure 38 to 49 percent in rats made acutely hypotensive by hemorrhage; other large neutral amino acids were ineffective. Tyrosine's effect was abolished by adrenalectomy, suggesting that, in hypotensive animals, it acts by accelerating the peripheral synthesis and release of catecholamines.