PMID- 8336821
OWN - NLM
STAT- MEDLINE
DCOM- 19930825
LR  - 20190726
IS  - 0028-3908 (Print)
IS  - 0028-3908 (Linking)
VI  - 32
IP  - 6
DP  - 1993 Jun
TI  - Effects of blockade of AT1 and AT2 receptors in brain on the central angiotensin 
      II pressor response in conscious spontaneously hypertensive rats.
PG  - 581-9
AB  - Intracerebroventricular (i.c.v.) administration of angiotensin II (ANG II) 
      increases vascular resistance and arterial pressure by increasing the activity in 
      the sympathetic nervous system (SNS-component) and secretion of vasopressin 
      (VP-component). This study examined the role of AT1 and AT2 receptors in brain in 
      mediating the exaggerated central cardiovascular effects of ANG II in conscious, 
      adult (10 weeks) spontaneously hypertensive rats (SHR). Mean arterial pressure, 
      heart rate and renal blood flow responses to intraventricular injection of ANG II 
      (100 ng in 5 microliters) were determined 10 min after intraventricular 
      administration of the AT1 receptor antagonist losartan alone (1.0, 2.5, 5.0, 10.0 
      micrograms), the AT2 receptor ligand PD 123319 alone (3.5 x [10(-6), 10(-4), 
      10(-2), 10(0)] micrograms), or both ligands in combination. In control rats, 
      intraventricular administration of losartan prevented the pressor and renal 
      vascular resistance responses to intraventricular injection of ANG II, in a 
      dose-dependent manner (P < 0.05), while intraventricular injection of PD 123319 
      was ineffective. Likewise, when the SNS- and VP-components were studied 
      individually by preventing the VP-component with a V1 receptor antagonist (i.v.) 
      or the SNS-component with chlorisondamine (i.v.), losartan (i.c.v.) prevented 
      both components, while PD 123319 (i.c.v.) was without affect. In addition, doses 
      of losartan, combined with 3.5 micrograms PD 123319, were no more effective in 
      preventing the pressor or renal vascular resistance responses than losartan, 
      administered alone, suggesting that the VP- and SNS-components of the pressor 
      response to ANG II (i.c.v.) are mediated primarily by AT1 receptors in brain in 
      conscious spontaneously hypertensive rats.(ABSTRACT TRUNCATED AT 250 WORDS)
FAU - Toney, G M
AU  - Toney GM
AD  - Department of Pharmacology, University of Texas Health Science Center, San 
      Antonio 78284-7764.
FAU - Porter, J P
AU  - Porter JP
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Neuropharmacology
JT  - Neuropharmacology
JID - 0236217
RN  - 0 (Angiotensin Receptor Antagonists)
RN  - 0 (Biphenyl Compounds)
RN  - 0 (Imidazoles)
RN  - 0 (Receptors, Angiotensin)
RN  - 0 (Tetrazoles)
RN  - 11128-99-7 (Angiotensin II)
RN  - JMS50MPO89 (Losartan)
SB  - IM
MH  - Analysis of Variance
MH  - Angiotensin II/antagonists & inhibitors/*pharmacology
MH  - Angiotensin Receptor Antagonists
MH  - Animals
MH  - Biphenyl Compounds/pharmacology
MH  - Blood Pressure/*drug effects/physiology
MH  - Brain/*drug effects
MH  - Heart Rate/drug effects/physiology
MH  - Hypertension/*physiopathology
MH  - Imidazoles/pharmacology
MH  - Injections, Intraventricular
MH  - Losartan
MH  - Male
MH  - Rats
MH  - Rats, Inbred SHR
MH  - Receptors, Angiotensin/*drug effects
MH  - Tetrazoles/pharmacology
MH  - Vascular Resistance/drug effects
EDAT- 1993/06/01 00:00
MHDA- 1993/06/01 00:01
CRDT- 1993/06/01 00:00
PHST- 1993/06/01 00:00 [pubmed]
PHST- 1993/06/01 00:01 [medline]
PHST- 1993/06/01 00:00 [entrez]
AID - 10.1016/0028-3908(93)90054-7 [doi]
PST - ppublish
SO  - Neuropharmacology. 1993 Jun;32(6):581-9. doi: 10.1016/0028-3908(93)90054-7.