AT1 receptors mediate pressor responses induced by angiotensin II in the periaqueductal gray area of rats.
Microinjection of angiotensin II (ANGII) (0.01 to 1 nmol) into the periaqueductal gray area (PAG) of anaesthetised rats caused dose-dependent increases in blood pressure. Preinjection (10 min before) of losartan (a selective non-peptide AT1 receptor antagonist; 50 nmol) to the PAG reduced the pressor response to ANGII whereas PD123319 (a selective non-peptide AT2 receptor antagonist; 50 nmol) did not affect the ANGII-induced hypertension. Thus, our data suggest that the activation of AT1 but not AT2 receptors mediates ANGII-induced blood pressure changes in the PAG area.
D'Amico
M
M
Institute of Pharmacology and Toxicology, Faculty of Medicine and Surgery, 2nd University of Naples, Italy.
Di Filippo
C
C
Berrino
L
L
Rossi
F
F
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D008297:Male; D010487:Periaqueductal Gray / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011945:Receptors, Angiotensin / Q000187:drug effects*
D011945:Receptors, Angiotensin; D000804:Angiotensin II