Characterization of angiotensin pressor responses in the turtle Pseudemys scripta

Am J Physiol. 1981 May;240(5):R276-81. doi: 10.1152/ajpregu.1981.240.5.R276.


Studies were conducted in turtles (Pseudemys scripta) to characterize vascular responses to administration of exogenous angiotensin [Asp1-Ile5]angiotensin II (AII). Marked pressor responses were present following AII administration (2 microgram/kg iv). The pressor response was completely blocked by concomitant administration of an analogue of AII, [Sar1-Ile8]AII. Both alpha-receptor blockade with phenoxybenzamine or catecholamine depletion by reserpine administration reduced the pressor response approximately 50%. Further treatment with [Sar1-Ile8]AII completely blocked the AII pressor response. We conclude that the pressor response to AII in this species that represents an ancient group of reptiles includes a catecholamine-dependent component and direct vascular receptors, both of which are sensitive to AII.

Publication types

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

MeSH terms

  • 1-Sarcosine-8-Isoleucine Angiotensin II / pharmacology
  • Angiotensin II / pharmacology
  • Angiotensin II / physiology*
  • Animals
  • Blood Pressure / drug effects*
  • Blood Vessels / innervation
  • Phenoxybenzamine / pharmacology
  • Receptors, Adrenergic / physiology
  • Reserpine / pharmacology
  • Turtles / physiology*


  • Receptors, Adrenergic
  • Phenoxybenzamine
  • Angiotensin II
  • Reserpine
  • 1-Sarcosine-8-Isoleucine Angiotensin II