Hemodynamic responses elicited by systemic injections of isotonic and hypertonic saline in hemorrhaged rats

Erin J Whalen; Alan Kim Johnson; Stephen J Lewis

doi:10.1016/j.mvr.2013.11.001

Back

Hemodynamic responses elicited by systemic injections of isotonic and hypertonic saline in hemorrhaged rats

Journal article

Peer reviewed

Hemodynamic responses elicited by systemic injections of isotonic and hypertonic saline in hemorrhaged rats

Erin J Whalen, Alan Kim Johnson and Stephen J Lewis

Microvascular research, Vol.91, pp.22-29

01/2014

DOI: 10.1016/j.mvr.2013.11.001

PMCID: PMC4389762

PMID: 24246569

Files and links (1)

url

http://doi.org/10.1016/j.mvr.2013.11.001View

Open Access

Abstract

The objectives of this study were (i) to characterize the hemodynamic responses caused by controlled hemorrhage (HEM) in pentobarbital-anesthetized rats, and (ii) to determine the responses elicited by systemic bolus injections of isotonic saline (0.15M) or hypertonic saline (3M) given 5min after completion of HEM. Controlled HEM (4.3±0.2ml/rat at 1.5ml/min) resulted in a pronounced and sustained fall in mean arterial blood pressure (MAP) to about 40mmHg. The fall in MAP was associated with a reduction in hindquarter vascular resistance (HQR) but no changes in renal (RR) or mesenteric (MR) vascular resistances. Systemic injections of isotonic saline (96-212μmol/kg i.v., in 250-550μl) did not produce immediate responses but promoted the recovery of MAP to levels below pre-HEM values. Systemic injections of hypertonic saline (750-3000μmol/kg, i.v., in 250-550μl) produced immediate and pronounced falls in MAP, RR, MR and especially HQR of 30-120s in duration. However, hypertonic saline prompted a full recovery of MAP, HQR and RR to pre-HEM levels and an increase in MR to levels above pre-HEM values. This study demonstrates that (i) HEM induced a pronounced fall in MAP which likely involved a fall in cardiac output and HQR, (ii) isotonic saline did not fully normalize MAP, and (iii) hypertonic saline produced dramatic initial responses, and promoted normalization of MAP probably by restoring blood volume and cardiac output through sequestration of fluid from intracellular compartments.

Blood Pressure

Shock, Hemorrhagic - pathology

Vascular Resistance

Renal Artery - pathology

Saline Solution, Hypertonic - chemistry

Mesenteric Arteries - pathology

Rats

Hydrodynamics

Male

Rats, Sprague-Dawley

Animals

Isotonic Solutions - chemistry

Time Factors

Pentobarbital - chemistry

Arterial Pressure - drug effects

Hemodynamics - drug effects

Vasodilation - drug effects

Hemorrhage - pathology

Details

Title: Subtitle: Hemodynamic responses elicited by systemic injections of isotonic and hypertonic saline in hemorrhaged rats
Creators: Erin J Whalen - Department of Psychology, University of Iowa, Iowa City, IA, USA; Department of Pharmacology, University of Iowa, Iowa City, IA, USA; The Cardiovascular Center, University of Iowa, Iowa City, IA, USA. Electronic address: erin.whalen@novartis.com
Alan Kim Johnson - Department of Psychology, University of Iowa, Iowa City, IA, USA; Department of Pharmacology, University of Iowa, Iowa City, IA, USA; The Cardiovascular Center, University of Iowa, Iowa City, IA, USA
Stephen J Lewis - Department of Pediatrics, Case Western Reserve University, Cleveland, OH, USA. Electronic address: sjl78@case.edu
Resource Type: Journal article
Publication Details: Microvascular research, Vol.91, pp.22-29
DOI: 10.1016/j.mvr.2013.11.001
PMID: 24246569
PMCID: PMC4389762
NLM abbreviation: Microvasc Res
ISSN: 0026-2862
eISSN: 1095-9319
Publisher: United States
Grant note: P01 HL101871 / NHLBI NIH HHS P01 HL014388 / NHLBI NIH HHS HL14388 / NHLBI NIH HHS R01 HL057472 / NHLBI NIH HHS HL57472 / NHLBI NIH HHS U10 HL109250 / NHLBI NIH HHS
Language: English
Date published: 01/2014
Academic Unit: Psychological and Brain Sciences; Neuroscience and Pharmacology; Health, Sport, and Human Physiology
Record Identifier: 9984002326302771

Metrics

22 Record Views

4 Times Cited - Web of Science