M. Brede et L. Hein, Transgenic mouse models of angiotensin receptor subtype function in the cardiovascular system, REGUL PEPT, 96(3), 2001, pp. 125-132
Angiotensin II mediates is biological actions via different subtypes of G p
rotein-coupled receptors, termed AT(1) and AT(2) receptors. In rodents, two
AT(1) receptors have been identified, AT(1A) and AT(1B), whereas in humans
a single AT(1) receptor exists. Recently, a number of transgenic animal mo
dels have been generated which overexpress or lack functional angiotensin I
I receptor subtypes. This review focuses on the physiological significance
of angiotensin II receptor subtype diversity in the cardiovascular system.
In the mouse, AT(1A) receptors are the major regulators of cardiovascular h
omeostasis by determining vascular tone and natriuresis. In addition, AT(1A
) receptors mediate growth-stimulating signals in vascular and cardiac myoc
ytes. AT(1B) receptors participate in blood pressure regulation, and their
functions become apparent when the AT(1A) receptor gene is deleted. Deletio
n of the mouse gene for the AT(2) receptor subtype led to hypersensitivity
to presser and antinatriuretic effects of angiotensin II in vivo, suggestin
g that the AT(2) receptor subtype counteracts some of the biological effect
s of AT(1) receptor signalling. (C) 2001 Elsevier Science B.V. All rights r
eserved.