Document Detail


Freeze tolerance in turtles: visual analysis by microscopy and magnetic resonance imaging.
MedLine Citation:
PMID:  7943419     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Two visual techniques were used to analyze the patterns of natural freezing and thawing in freeze-tolerant hatchling painted turtles Chrysemys picta marginata. Directional solidification plus light microscopy of liver, heart, and skeletal muscle slices was used to compare freezing at -4 degrees C (a survivable temperature in vivo) and -20 degrees C (not survivable). At -4 degrees C tissues showed large amounts of ice in expanded extracellular and vascular spaces, occupying 36% (liver) and 61% (muscle) of total tissue volume. Cells at -4 degrees C were shrunken, but intracellular water remained; at -20 degrees C, however, cells showed little evidence of free water. Liver micrographs showed novel spherical shells of water associated with intracellular particles (apparently glycogen granules) suggesting that a noncolligative method of cell water retention was employed. Proton magnetic resonance imaging was used for noninvasive analysis of freezing and thawing in the intact animal. Images showed that freezing propagated in a directional manner through the body with ice formed first in extraorgan spaces (e.g., abdominal cavity, brain ventricles). However, thawing occurred uniformly throughout the body core, and organs melted more rapidly than the extraorgan ice surrounding them.
Authors:
B Rubinsky; J S Hong; K B Storey
Related Documents :
479409 - Ct studies of the liver in vitro: a report on 82 cases with pathological correlation.
17981419 - Imaging findings of liver involvement of wilson's disease.
12357079 - Magnetic resonance imaging of diffuse liver diseases.
12594549 - Detection of liver metastases by pulse inversion harmonic imaging during levovist late ...
15332259 - Inflammatory pseudotumor of the liver: ferumoxide-enhanced mr imaging as a tiebreaker.
2121409 - In vivo tissue pharmacokinetics by fluorine magnetic resonance spectroscopy: a study of...
10555679 - The aapm/rsna physics tutorial for residents. mr imaging safety considerations. radiolo...
17369019 - Computer assistance for mr based diagnosis of breast cancer: present and future challen...
23417229 - Diffusion-weighted mr imaging of fetal lung maturation in sheep: effect of prenatal cor...
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, Non-P.H.S.; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The American journal of physiology     Volume:  267     ISSN:  0002-9513     ISO Abbreviation:  Am. J. Physiol.     Publication Date:  1994 Oct 
Date Detail:
Created Date:  1994-11-18     Completed Date:  1994-11-18     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  0370511     Medline TA:  Am J Physiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  R1078-88     Citation Subset:  IM    
Affiliation:
Department of Mechanical Engineering, University of California, Berkely 94720.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Acclimatization*
Animals
Freezing*
Heart / physiology*
Liver / cytology,  physiology*
Magnetic Resonance Imaging / methods
Microscopy
Muscles / cytology,  physiology*
Myocardium / cytology
Turtles / physiology*
Grant Support
ID/Acronym/Agency:
GM-43796/GM/NIGMS NIH HHS

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


Previous Document:  Involvement of capsaicin-sensitive nerves in regulation of insulin secretion and glucose tolerance i...
Next Document:  Hypothalamic thermal stimulation modulates vasopressin release in hyperosmotically stimulated rabbit...