PMID- 12426052
OWN - NLM
STAT- MEDLINE
DCOM- 20030129
LR  - 20190614
IS  - 0006-8993 (Print)
IS  - 0006-8993 (Linking)
VI  - 956
IP  - 1
DP  - 2002 Nov 22
TI  - Central serotonergic and adrenergic/imidazoline inhibitory mechanisms on sodium 
      and water intake.
PG  - 103-9
AB  - Recent studies have shown the existence of two important inhibitory mechanisms 
      for the control of NACL and water intake: one mechanism involves serotonin in the 
      lateral parabrachial nucleus (LPBN) and the other depends on 
      alpha(2)-adrenergic/imidazoline receptors probably in the forebrain areas. In the 
      present study we investigated if alpha(2)-adrenergic/imidazoline and serotonergic 
      inhibitory mechanisms interact to control NaCl and water intake. Male Holtzman 
      rats with cannulas implanted simultaneously into the lateral ventricle (LV) and 
      bilaterally into the LPBN were used. The ingestion of 0.3 M NaCl and water was 
      induced by treatment with the diuretic furosemide (10 mg/kg of body weight)+the 
      angiotensin converting enzyme inhibitor captopril (5 mg/kg) injected 
      subcutaneously 1 h before the access of rats to water and 0.3 M NaCl. 
      Intracerebroventricular (i.c.v.) injection of the alpha(2)-adrenergic/imidazoline 
      agonist clonidine (20 nmol/1 microl) almost abolished water (1.6+/-1.2, vs. 
      vehicle: 7.5+/-2.2 ml/2 h) and 0.3 M NaCl intake (0.5+/-0.3, vs. vehicle: 
      2.2+/-0.8 ml/2 h). Similar effects were produced by bilateral injections of the 
      5HT(2a/2c) serotonergic agonist 2,5-dimetoxy-4-iodoamphetamine (DOI, 5 microg/0.2 
      microl each site) into the LPBN on water (3.6+/-0.9 ml/2 h) and 0.3 M NaCl intake 
      (0.4+/-0.2 ml/2 h). Injection of the alpha(2)-adrenergic/imidazoline antagonist 
      idazoxan (320 nmol) i.c.v. completely blocked the effects of clonidine on water 
      (8.4+/-1.5 ml/2 h) and NaCl intake (4.0+/-1.2 ml/2 h), but did not change the 
      effects of LPBN injections of DOI on water (4.2+/-1.0 ml/2 h) and NaCl intake 
      (0.7+/-0.2 ml/2 h). Bilateral injections of methysergide (4 microg/0.2 microl 
      each site) into the LPBN increased 0.3 M NaCl intake (6.4+/-1.9 ml/2 h), not 
      water intake. The inhibitory effect of i.c.v. clonidine on water and 0.3 M NaCl 
      was still present after injections of methysergide into the LPBN (1.5+/-0.8 and 
      1.7+/-1.4 ml/2 h, respectively). The results show that the inhibitory effects of 
      the activation of alpha(2)-adrenergic/imidazoline receptors in the forebrain are 
      still present after blockade of the LPBN serotonergic mechanisms and vice versa 
      for the activation of serotonergic mechanisms of the LPBN. Therefore, each system 
      may act independently to inhibit NaCl and water intake.
FAU - Oliveira Margatho, Lisandra
AU  - Oliveira Margatho L
AD  - Department of Physiology and Pathology, School of Dentistry, Paulista State 
      University-UNESP, Rua Humaita, 1680 14801-903, SP, Araraquara, Brazil.
FAU - Pereira Barbosa, Silas
AU  - Pereira Barbosa S
FAU - Antonio De Luca, Laurival Jr
AU  - Antonio De Luca L Jr
FAU - Vanderlei Menani, Jose
AU  - Vanderlei Menani J
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Netherlands
TA  - Brain Res
JT  - Brain research
JID - 0045503
RN  - 0 (Amphetamines)
RN  - 0 (Angiotensin-Converting Enzyme Inhibitors)
RN  - 0 (Diuretics)
RN  - 0 (Imidazoline Receptors)
RN  - 0 (Receptors, Drug)
RN  - 0 (Receptors, Serotonin)
RN  - 0 (Serotonin Antagonists)
RN  - 0 (Serotonin Receptor Agonists)
RN  - 0 (Sodium Chloride, Dietary)
RN  - 7LXU5N7ZO5 (Furosemide)
RN  - 9G64RSX1XD (Captopril)
RN  - MN3L5RMN02 (Clonidine)
RN  - OOM10GW9UE (4-iodo-2,5-dimethoxyphenylisopropylamine)
RN  - XZA9HY6Z98 (Methysergide)
RN  - Y310PA316B (Idazoxan)
SB  - IM
MH  - Amphetamines/administration & dosage/pharmacology
MH  - Angiotensin-Converting Enzyme Inhibitors/pharmacology
MH  - Animals
MH  - Captopril/pharmacology
MH  - Cerebellar Nuclei/drug effects/physiology
MH  - Clonidine/administration & dosage/pharmacology
MH  - Diuretics/pharmacology
MH  - Drinking/drug effects/*physiology
MH  - Drinking Behavior/drug effects/*physiology
MH  - Furosemide/pharmacology
MH  - Idazoxan/administration & dosage/pharmacology
MH  - Imidazoline Receptors
MH  - Injections, Intraventricular
MH  - Male
MH  - Methysergide/administration & dosage/pharmacology
MH  - Rats
MH  - Rats, Sprague-Dawley
MH  - Receptors, Drug/*physiology
MH  - Receptors, Serotonin/*physiology
MH  - Serotonin Antagonists/administration & dosage/pharmacology
MH  - Serotonin Receptor Agonists/administration & dosage/pharmacology
MH  - *Sodium Chloride, Dietary
EDAT- 2002/11/12 04:00
MHDA- 2003/01/30 04:00
CRDT- 2002/11/12 04:00
PHST- 2002/11/12 04:00 [pubmed]
PHST- 2003/01/30 04:00 [medline]
PHST- 2002/11/12 04:00 [entrez]
AID - S0006899302034868 [pii]
AID - 10.1016/s0006-8993(02)03486-8 [doi]
PST - ppublish
SO  - Brain Res. 2002 Nov 22;956(1):103-9. doi: 10.1016/s0006-8993(02)03486-8.