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Title: Effects of perfusion pressure and insulin on (/sup 3/H) cytochalasin B (CB) binding to control and diabetic rat hearts

Abstract

Using (/sup 3/H) CB, they attempted to quantitate the changes in the amount of glucose transporters in the plasma membrane (PM) and intracellular membranes (HSP) prepared from rat hearts perfused with insulin, under low and high pressure. Membranes isolated from non-perfused hearts showed a PM/HSP ratio of (0.593). Hearts perfused with low pressure showed a lower ratio of (0.474). Perfusion with insulin increased the ratio to (1.8), almost a 3-4 fold increase from low perfusion pressure. These data correlate with insulin effects in glucose transport and CB binding in the fat cells. High pressure perfusion increased the PM/HSP ratio by 1-2 fold. (/sup 3/H) 2-DG transport indicates a comparable increase in glucose uptake with high pressure, but with insulin only a 1.5 fold increase was observed. Initial data obtained from streptozotocin (STZ) injected diabetic rats indicate low CB binding in the PM fraction. Only insulin, but not high perfusion pressure increased PM/HSP ratio in the STZ-diabetic hearts. Their data imply that while both caused apparent translocation of glucose transporters, influences on cardiac glucose metabolism by work load are different. Furthermore, STZ induced diabetes affected only the high perfusion pressure-induced and not the insulin-stimulated change in CB binding.

Authors:
;
Publication Date:
Research Org.:
Univ. of Southern California, Los Angeles
OSTI Identifier:
6173443
Alternate Identifier(s):
OSTI ID: 6173443
Report Number(s):
CONF-870644-
Journal ID: CODEN: FEPRA
Resource Type:
Conference
Resource Relation:
Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States); Journal Volume: 46:6; Conference: 78. annual meeting of the American Society of Biological Chemists conference, Philadelphia, PA, USA, 7 Jun 1987
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; DIABETES MELLITUS; PATHOGENESIS; GLUCOSE; MEMBRANE TRANSPORT; METABOLISM; PROTEINS; BIOCHEMICAL REACTION KINETICS; CELL MEMBRANES; HEART; INSULIN; PERFUSED ORGANS; RATS; TRACER TECHNIQUES; TRITIUM COMPOUNDS; ALDEHYDES; ANIMALS; BODY; CARBOHYDRATES; CARDIOVASCULAR SYSTEM; CELL CONSTITUENTS; DISEASES; ENDOCRINE DISEASES; HEXOSES; HORMONES; ISOTOPE APPLICATIONS; KINETICS; LABELLED COMPOUNDS; MAMMALS; MEMBRANES; METABOLIC DISEASES; MONOSACCHARIDES; ORGANIC COMPOUNDS; ORGANS; PEPTIDE HORMONES; REACTION KINETICS; RODENTS; SACCHARIDES; VERTEBRATES 550201* -- Biochemistry-- Tracer Techniques; 550901 -- Pathology-- Tracer Techniques

Citation Formats

Pleta, M., and Chan, T. Effects of perfusion pressure and insulin on (/sup 3/H) cytochalasin B (CB) binding to control and diabetic rat hearts. United States: N. p., 1987. Web.
Pleta, M., & Chan, T. Effects of perfusion pressure and insulin on (/sup 3/H) cytochalasin B (CB) binding to control and diabetic rat hearts. United States.
Pleta, M., and Chan, T. Fri . "Effects of perfusion pressure and insulin on (/sup 3/H) cytochalasin B (CB) binding to control and diabetic rat hearts". United States. doi:.
@article{osti_6173443,
title = {Effects of perfusion pressure and insulin on (/sup 3/H) cytochalasin B (CB) binding to control and diabetic rat hearts},
author = {Pleta, M. and Chan, T.},
abstractNote = {Using (/sup 3/H) CB, they attempted to quantitate the changes in the amount of glucose transporters in the plasma membrane (PM) and intracellular membranes (HSP) prepared from rat hearts perfused with insulin, under low and high pressure. Membranes isolated from non-perfused hearts showed a PM/HSP ratio of (0.593). Hearts perfused with low pressure showed a lower ratio of (0.474). Perfusion with insulin increased the ratio to (1.8), almost a 3-4 fold increase from low perfusion pressure. These data correlate with insulin effects in glucose transport and CB binding in the fat cells. High pressure perfusion increased the PM/HSP ratio by 1-2 fold. (/sup 3/H) 2-DG transport indicates a comparable increase in glucose uptake with high pressure, but with insulin only a 1.5 fold increase was observed. Initial data obtained from streptozotocin (STZ) injected diabetic rats indicate low CB binding in the PM fraction. Only insulin, but not high perfusion pressure increased PM/HSP ratio in the STZ-diabetic hearts. Their data imply that while both caused apparent translocation of glucose transporters, influences on cardiac glucose metabolism by work load are different. Furthermore, STZ induced diabetes affected only the high perfusion pressure-induced and not the insulin-stimulated change in CB binding.},
doi = {},
journal = {Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)},
number = ,
volume = 46:6,
place = {United States},
year = {Fri May 01 00:00:00 EDT 1987},
month = {Fri May 01 00:00:00 EDT 1987}
}

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