PMID- 17244943
OWN - NLM
STAT- MEDLINE
DCOM- 20080327
LR  - 20151119
IS  - 1899-1505 (Electronic)
IS  - 0867-5910 (Linking)
VI  - 57 Suppl 11
DP  - 2006 Nov
TI  - Cardiovascular effects of centrally acting orexin A in haemorrhage-shocked rats.
PG  - 115-24
AB  - Orexin A influences the central cardiovascular regulation, since after 
      intracerebroventricular (icv) administration it evokes short-lasting increases in 
      mean arterial pressure (MAP) and heart rate (HR) in normotensive animals. The aim 
      of the present study was to examine haemodynamic effects of orexin A in 
      haemorrhage-shocked rats. Experiments were carried out in anaesthetized Wistar 
      rats subjected for a critical irreversible haemorrhagic hypotension of 20-25 
      mmHg, which resulted in the death of all saline icv-treated control animals 
      within 30 min. Orexin A (0.5-1.5 nmol; icv) administered at 5 min of critical 
      hypotension evoked dose-dependent long-lasting increases in MAP, HR and renal, 
      mesenteric and hindquarters blood flows, with a 100% survival of 2 h after 
      treatment (1.5 nmol; icv). Changes in MAP and peripheral haemodynamics were 
      inhibited by intravenous pretreatment with alpha(1)- and alpha(2)-adrenoceptor 
      antagonists prazosin (0.5 mg/kg) and yohimbine (1.0 mg/kg), respectively. 
      Moreover, both antagonists significantly decreased the survival rate to 16.6 and 
      33.3% (P<0.05 vs. orexin A [1.5 nmol]-treated group). In contrast, 
      beta-adrenoceptor antagonist propranolol (1.0 mg/kg) completely blocked orexin 
      A-induced HR changes, without influence on MAP, peripheral blood flows and the 
      survival rate. Therefore, we conclude that centrally acting orexin A evokes the 
      resuscitating effect in haemorrhage-shocked rats due to the activation of the 
      sympathetic nervous system.
FAU - Jochem, J
AU  - Jochem J
AD  - Department of Physiology, Medical University of Silesia, Zabrze, Poland. 
      jjochem@poczta.onet.pl
FAU - Zwirska-Korczala, K
AU  - Zwirska-Korczala K
FAU - Zabielski, R
AU  - Zabielski R
FAU - Kato, I
AU  - Kato I
FAU - Kuwahara, A
AU  - Kuwahara A
LA  - eng
PT  - Journal Article
PL  - Poland
TA  - J Physiol Pharmacol
JT  - Journal of physiology and pharmacology : an official journal of the Polish 
      Physiological Society
JID - 9114501
RN  - 0 (Adrenergic alpha-Antagonists)
RN  - 0 (Adrenergic beta-Antagonists)
RN  - 0 (HCRT protein, human)
RN  - 0 (Intracellular Signaling Peptides and Proteins)
RN  - 0 (Neuropeptides)
RN  - 0 (Orexins)
RN  - 0 (Sympathomimetics)
RN  - 2Y49VWD90Q (Yohimbine)
RN  - 9Y8NXQ24VQ (Propranolol)
RN  - XM03YJ541D (Prazosin)
SB  - IM
MH  - Adrenergic alpha-Antagonists/pharmacology
MH  - Adrenergic beta-Antagonists/pharmacology
MH  - Animals
MH  - Blood Pressure/drug effects
MH  - Cardiovascular System/*drug effects
MH  - Dose-Response Relationship, Drug
MH  - Heart Rate/drug effects
MH  - Humans
MH  - Hypotension/etiology/metabolism/physiopathology
MH  - Injections, Intraventricular
MH  - Intracellular Signaling Peptides and Proteins/administration & 
      dosage/*pharmacology/physiology
MH  - Male
MH  - Neuropeptides/administration & dosage/*pharmacology/physiology
MH  - Orexins
MH  - Prazosin/pharmacology
MH  - Propranolol/pharmacology
MH  - Rats
MH  - Rats, Wistar
MH  - Regional Blood Flow/drug effects
MH  - Shock, Hemorrhagic/complications/metabolism/*physiopathology
MH  - Sympathetic Nervous System/drug effects/physiopathology
MH  - Sympathomimetics/administration & dosage/*pharmacology
MH  - Yohimbine/pharmacology
EDAT- 2007/01/25 09:00
MHDA- 2008/03/28 09:00
CRDT- 2007/01/25 09:00
PHST- 2006/11/21 00:00 [received]
PHST- 2006/11/24 00:00 [accepted]
PHST- 2007/01/25 09:00 [pubmed]
PHST- 2008/03/28 09:00 [medline]
PHST- 2007/01/25 09:00 [entrez]
PST - ppublish
SO  - J Physiol Pharmacol. 2006 Nov;57 Suppl 11:115-24.