PMID- 10704785
OWN - NLM
STAT- MEDLINE
DCOM- 20000324
LR  - 20190719
IS  - 0361-9230 (Print)
IS  - 0361-9230 (Linking)
VI  - 51
IP  - 4
DP  - 2000 Mar 1
TI  - Brain AT(2) receptor mediate vasodepressor response to footshocks: role of kinins 
      and nitric oxide.
PG  - 339-43
AB  - In the present study the role of brain AT(2) receptor in the cardiovascular 
      response to stress was investigated in conscious rats. Footshock-stress increased 
      mean arterial pressure (MAP) and heart rate (p < 0.0001). Intracerebroventricular 
      (i.c.v.) administration of losartan (100 microg/5 microl), a specific angiotensin 
      AT(1) receptor antagonist, not only attenuated the pressor response to 
      footshocks, but also resulted in a consistent vasodepressor response (-10 mmHg, p 
      < 0.02). Meanwhile, heart rate response was not altered. Given alone, PD 123319 
      (3 microg/5 microl, i.c.v.), a specific angiotensin AT(2) receptor antagonist, 
      did not alter the hemodynamic response to footshocks. However, simultaneous block 
      of brain AT(1) and AT(2) receptors by combined administration of losartan and PD 
      12319, eliminated the vasodepressor response unmasked after footshocks in rats 
      i.c.v.-pretreated with losartan alone. In addition, we studied the role of brain 
      kinins and nitric oxide (NO) in the vasodepressor response observed after 
      footshocks in losartan i.c.v.-treated rats. Intracerebroventricular 
      administration of icatibant (20 pmol/5 microl), a selective B(2) receptor 
      antagonist, or N(G)-nitro-L-arginine methyl ester (100 microg/5 microl), a 
      selective NO-synthase inhibitor, abolished the vasodepressor response to 
      footshocks in losartan-treated rats. Our data suggest that the vasodepressor 
      response to footshocks in the presence of AT(1) antagonist is triggered by 
      activation of AT(2) receptor. Brain NO and kinins appear to contribute in this 
      effect.
FAU - Israel, A
AU  - Israel A
AD  - School of Pharmacy, Universidad Central de Venezuela, Caracas Schools of 
      Medicine, Caracas, Venezuela. astern88@hotmail.com
FAU - Sosa, B
AU  - Sosa B
FAU - Gutierez, C I
AU  - Gutierez CI
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Brain Res Bull
JT  - Brain research bulletin
JID - 7605818
RN  - 0 (Angiotensin Receptor Antagonists)
RN  - 0 (Bradykinin Receptor Antagonists)
RN  - 0 (Enzyme Inhibitors)
RN  - 0 (Imidazoles)
RN  - 0 (Pyridines)
RN  - 0 (Receptor, Angiotensin, Type 1)
RN  - 0 (Receptor, Angiotensin, Type 2)
RN  - 0 (Receptor, Bradykinin B2)
RN  - 0 (Receptors, Angiotensin)
RN  - 11128-99-7 (Angiotensin II)
RN  - 130663-39-7 (PD 123319)
RN  - 2149-70-4 (Nitroarginine)
RN  - 7PG89G35Q7 (icatibant)
RN  - EC 1.14.13.39 (Nitric Oxide Synthase)
RN  - JMS50MPO89 (Losartan)
RN  - S8TIM42R2W (Bradykinin)
SB  - IM
MH  - Angiotensin II/metabolism/*physiology
MH  - Angiotensin Receptor Antagonists
MH  - Animals
MH  - Blood Pressure/drug effects/*physiology
MH  - Bradykinin/analogs & derivatives/pharmacology
MH  - Bradykinin Receptor Antagonists
MH  - Brain/*metabolism
MH  - Electroshock
MH  - Enzyme Inhibitors/pharmacology
MH  - Extremities
MH  - Heart Rate/drug effects/physiology
MH  - Imidazoles/pharmacology
MH  - Injections, Intraventricular
MH  - Losartan/pharmacology
MH  - Male
MH  - Nitric Oxide Synthase/antagonists & inhibitors
MH  - Nitroarginine/pharmacology
MH  - Pyridines/pharmacology
MH  - Rats
MH  - Rats, Sprague-Dawley
MH  - Receptor, Angiotensin, Type 1
MH  - Receptor, Angiotensin, Type 2
MH  - Receptor, Bradykinin B2
MH  - Receptors, Angiotensin/metabolism/*physiology
EDAT- 2000/03/08 09:00
MHDA- 2000/04/01 09:00
CRDT- 2000/03/08 09:00
PHST- 2000/03/08 09:00 [pubmed]
PHST- 2000/04/01 09:00 [medline]
PHST- 2000/03/08 09:00 [entrez]
AID - S0361-9230(99)00244-0 [pii]
AID - 10.1016/s0361-9230(99)00244-0 [doi]
PST - ppublish
SO  - Brain Res Bull. 2000 Mar 1;51(4):339-43. doi: 10.1016/s0361-9230(99)00244-0.