Document Detail


Effects of low temperature on contraction in papillary muscles from rabbit, rat, and hedgehog.
MedLine Citation:
PMID:  2249456     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
During hibernation the body temperature may fall to only a few degrees above 0 degree C. The heart of the hedgehog continues to function whereas the hearts of nonhibernating mammals stop beating. The present study was performed to investigate and compare the mechanical responses to hypothermia in rabbits, rats, and hedgehogs. Isometric force was recorded from papillary muscles mounted in an organ bath and effects of hypothermia on the mechanical restitution curve were also compared. A reduction of bath temperature from 35 degrees C caused an increase in peak developed force. Maximum force was seen at 20 degrees C in the rabbit, 15 degrees C in the rat, and 10 degrees C in the hedgehog preparations. In all the species there was a similar prolongation of time to peak force and of time from peak to half-relaxation as temperature was lowered. An increase in resting force and after-contractions were recorded in the rabbit and rat muscles at temperatures below 15 and 10 degrees C, respectively. The rabbit and rat preparations became inexcitable at temperatures below 10 and 5 degrees C, respectively. The hedgehog papillary muscle, on the other hand, still contracted at 0 degree C and did not show increased resting force nor after-contractions. The results are consistent with the hypothesis that there is a calcium overload in cardiac cells from rabbit and rat at low temperatures but there is no calcium overload in the hedgehog muscle during hypothermia.
Authors:
B Liu; B Wohlfart; B W Johansson
Related Documents :
2100316 - Is increased metabolism in rats in the cold mediated by the thyroid?
7752956 - Effects of age, reproductive status and ambient temperature on skin temperature regulat...
7182476 - Facial thermal input in the caudal trigeminal nucleus of rats reared at 30 degrees c.
15028756 - Inhibitory control at a synaptic relay.
15093886 - Role of angiotensin ii type 2 receptors and kinins in the cardioprotective effect of an...
9111766 - Analysis of the derangement of the pancreatic microcirculation in a rat caerulein pancr...
Publication Detail:
Type:  Comparative Study; In Vitro; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Cryobiology     Volume:  27     ISSN:  0011-2240     ISO Abbreviation:  Cryobiology     Publication Date:  1990 Oct 
Date Detail:
Created Date:  1991-01-15     Completed Date:  1991-01-15     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  0006252     Medline TA:  Cryobiology     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  539-46     Citation Subset:  IM    
Affiliation:
Department of Pharmacology, University of Lund, Sweden.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Calcium / metabolism
Cold Temperature*
Hedgehogs
Hibernation / physiology
Hypothermia / physiopathology
Myocardial Contraction / physiology*
Papillary Muscles / physiology*
Rabbits
Rats
Species Specificity
Chemical
Reg. No./Substance:
7440-70-2/Calcium

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Mechanism of freeze-thaw damage to liver alcohol dehydrogenase and protection by cryoprotectants and...
Next Document:  Freezing of isolated thylakoid membranes in complex media. VI. The effect of pH.