الفهرس 
Introduction
Chemical composition of PropylthiouracilOnly 14 pages are availabe for public view
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Abstract
Thyroid hormones are secreted to control tissue metabolism rate, so any
alteration in their action will affect the system of many organs and change
many enzymes level including liver enzymes; Aspartate Amino Transferase
(AST), Alanine Amino Transferase (ALT), total serum cholesterol, urea and
creatinine. The study is conducted to investigate the effect of Propylthiouracilinduced
hypothyroidism on the liver and kidney functions in rabbits.
This investigation was performed on male, white New Zealand rabbits
(Oryctolagus cuniculus huxley). Forty rabbits were used; each of the four
groups consisted of ten animals.
Hypothyroidism was induced by oral administration of Propylthiouracil
50, 75, 150 mg/kg. body weight for three weeks.Estimation of T3,T4 and TSH
using Vidas, liver enzymes blood serum AST ,ALT was determined using
kinetic method, kidney function tests Blood Urea Nitrogen was determined
using urease-colorimetric method and creatinine was determined from the
reaction of creatinine with sodium picrate using commercial kites.
At the end of the experiment animals were scarified and exposed for PM
examination and tissue samples from thyroid, livers and kidneys were taken,
kept in buffered formalin 10% and subjected for histopathological
examination.
All animals were clinically healthy and no abnormal clinical findings
were observed at beginning of the study. However, after 3 weeks animals
except control group suffered from hypothyroidism showed general weakness,
lazy and not active and no other prominent clinical signs were reported.
The results showed significant decrease in T3 in the second, third and
fourth groups reached (61.0 ± 4.2 ng/ml), T4 showed significant decrease in
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the second, third and fourth groups (0.95 ± 0.17 ug/ml), non-significant
increase and TSH 0.07 uIU/ml. In liver enzymes increase blood serum AST
(79 ± 5.6 U/ml) and blood serum ALT highest values of ALT (247 ± 18.14
U/ml) and a significant increase in blood serum cholesterol leve (135±29.6
mg/dl).
As for kidney function, there was and a non-significant increase in blood
urea nitrogen level (48.4±2.8 mg/dl) and a significant increase in serum
creatinine level (2.01±1.95 mg/dl).
Histological examination of thyroid glands revealed in hypothyroid
Propylthiouracil treated groups: group II (treated with PTU 50 mg/kg bwt for 3
weeks), group III (treated with PTU 75 mg/kg bwt for 3 weeks) and group IV
(treated with PTU 150 mg/kg bwt for 3 weeks) thyroids presented altered
follicles with varied sizes, lined by vacuolated follicular cells. In some
follicles, multiple layers of follicular cells were seen, filled with a variable
quantity of little dense and very vacuolated colloid. There were also pools of
follicular cells devoid of lumen (interfollicular adenomatosis). The severity of
hypothyroid changes increased from mild in group (II) to moderate (III) till
severe in the (IV) group according to the increased administrated dose
Histopathological examination of the liver sections showed
histopathological changes in the form of severe congestion in central vein and
hepatic artery. Hepatocellular necrosis, the epithelium lining central veins were
degenerated and desquamated. The presence of lymphocytic cellular reactions
around portal areas. In addition, dissociation of hepatic cords arrangements
affected hepatic architectures.Variable hepatic injury differed in severity
according to the administrated dose.
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kidney of hypothyroid rabbits showed variable pathological changes in
glomeruli and some parts of the urinary tubules. Congested vessels, the
glomeruli were atrophied and lost their cellular configuration and the renal
tubuler epithelium was degenerated. Focal aggregations of lymphocytes were
also present.
This study demonstrates that there is an a positive association between
decreased thyroid hormones levels and liver enzymes levels Aspartate Amino
Transferase (AST), Alanine Amino Transferase (ALT), total serum cholesterol,
urea and creatinine., cholesterol, urea and creatinine.
The study also evaluates the histopathological changes in kidney, liver