Vol 63, No 4 (2004)
Original article
Submitted: 2012-02-06
Published online: 2004-09-16
Myocardial necrosis due to vitamin D3 overdose - scanning electron microscopic observations
Olga Walentynowicz, Jolanta Kubasik-Juraniec, Teresa Rudzińska-Kisiel
Folia Morphol 2004;63(4):439-444.
Vol 63, No 4 (2004)
ORIGINAL ARTICLES
Submitted: 2012-02-06
Published online: 2004-09-16
Abstract
Our studies were carried out on the hearts of virgin female Wistar rats treated
with 100.000 i.u. of vitamin D3 (calciol) per os for 3 consecutive days. Multifocal
cardionecrosis was established macroscopically in 70% of the vitamin D-treated
rats on the 7th day of the experiment when the rats were in the acute phase of
intoxication.
Using a scanning electron microscopy (SEM), we received three-dimensional information
about the structural changes to the rat myocardium damaged by
high doses of vitamin D3. The images of necrotic hearts revealed significant
disruption of the structural integrity of the myocardium linked to fragmentation
of the cardiac muscle bundles and a visible disruption of the extracellular matrix
(ECM) components. In healthy hearts, the structural integrity of the myocardium
and the dense network of the extracellular matrix were well preserved. In parallel,
the effect of an increasing concentration of free Ca2+ on the total proteolytic
activity of the heart muscle homogenate of the healthy and necrotic rats was
investigated at neutral pH. These data showed that following vitamin D3 intoxication,
the proteolytic processes in the rat hearts occurred in Ca2+ overload or
saturation. On the basis of our morphological and biochemical results we can
suggest that calcium-activated neutral proteinases may have contributed to the
structural alteration of the extracellular matrix components and were in this way
involved in vitamin D-induced cardionecrosis.
Abstract
Our studies were carried out on the hearts of virgin female Wistar rats treated
with 100.000 i.u. of vitamin D3 (calciol) per os for 3 consecutive days. Multifocal
cardionecrosis was established macroscopically in 70% of the vitamin D-treated
rats on the 7th day of the experiment when the rats were in the acute phase of
intoxication.
Using a scanning electron microscopy (SEM), we received three-dimensional information
about the structural changes to the rat myocardium damaged by
high doses of vitamin D3. The images of necrotic hearts revealed significant
disruption of the structural integrity of the myocardium linked to fragmentation
of the cardiac muscle bundles and a visible disruption of the extracellular matrix
(ECM) components. In healthy hearts, the structural integrity of the myocardium
and the dense network of the extracellular matrix were well preserved. In parallel,
the effect of an increasing concentration of free Ca2+ on the total proteolytic
activity of the heart muscle homogenate of the healthy and necrotic rats was
investigated at neutral pH. These data showed that following vitamin D3 intoxication,
the proteolytic processes in the rat hearts occurred in Ca2+ overload or
saturation. On the basis of our morphological and biochemical results we can
suggest that calcium-activated neutral proteinases may have contributed to the
structural alteration of the extracellular matrix components and were in this way
involved in vitamin D-induced cardionecrosis.
Keywords
cardiac myocytes; calciol; toxicity; extracellular matrix; calpain
Title
Myocardial necrosis due to vitamin D3 overdose - scanning electron microscopic observations
Journal
Folia Morphologica
Issue
Vol 63, No 4 (2004)
Article type
Original article
Pages
439-444
Published online
2004-09-16
Page views
517
Article views/downloads
1295
Bibliographic record
Folia Morphol 2004;63(4):439-444.
Keywords
cardiac myocytes
calciol
toxicity
extracellular matrix
calpain
Authors
Olga Walentynowicz
Jolanta Kubasik-Juraniec
Teresa Rudzińska-Kisiel
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