Abstract
Background: Fluorides ,when taken in amounts exceeding the standard
therapeutic dosage ,are regarded as toxic substance producing histopathological
changes in many organs.
The aim of this work :was to investigate the effects of antioxidarive vitamins
A,c,g on the structure of rat pancreas exposed to high doses of sodium fluoride.
Materials and Methods: Twenty one adult male rats were divided into three
equal groups: The control group, fluoride group and fluoride plus vitamins (A, C
and E) group .In the co; trol group ,the rats were given 2m1 of distilled water /kg
.B. W. orally once daily for 35 days. In fluoride group, the rats were given fluoride
orally at dose of .romg Naf /kg .B.W. once daily for 35 days. In fluoride plus
vitamins group, the rats were given fluoride as the second group ,in addition to
vitamins A, C and Eat dose of 250mg/kg .B.W for each of vitamin C &E and woo
IU/kg for vitamin A. All animals were sacrificed after 35 days .The pancreatic
specimens were preparedfor light and electron microscopies.
Results: the sodium fluoride produced congestion of blood vessels and blood
capillaries distributed between the pancreatic acini and the blood sinusoids of the
islets of Langerhans .There were extravasations of blood cells in the interstitial
spaces where the wall of blood sinusoid was damaged . The pancreatic acini
showed varying degrees of changes :some acini contained many vacuoles with
intact nuclei and basement membrane . Other acini showed loss of their
architectures and necrosis of most of their cells which were replaced by vacuoles.
The connective tissue fibers were increased around the blood vessels ,degenerated
and vacuolated pancreatic acini. By electron microscopic examination, the rat
pancreas showed dilatations of the cisterns of the endoplasmic reticulum
,degenerations of some mitochondria "eduction in the numbers of zymogen
granules and appearance of large vesicles and phagosome. The only change in the
cells of islet of Langerhans was decreasing in the numbers of granules especially
the Beta cells which secretes the insulin .By administration of vitamins A,C,E during
the fluoride treatment ,the pathological changes induced by fluoride were reduced.
Few acinar cells contained vacuoles .The cells of islet of Langerhans were
apparently intact, the connective tissue fibers became minimal in amount. The
electron microscopic examination showed some dilated cisterns of endoplasmic
reticulum and few degenerated mitochondria.
Conclusion: The most toxic effects offluoride on the pancreas were pancreatica
heamorrhagica, disruption of the export of zymog en granules and increase in the
fibrosis. These effects can be minimized by administration of combination of
vitamins A, C and E. |
