Histological study on withdrwal of chronic lithium therapy on rabbits thyroid

Sixty male adult albino rabbits were divided into two groups, control and experimental. Each group was divided into three sub-groups. Lithium Carbonate powder 34.2 mg per kg body weight was administered daily by oral route in the form of capsule for four weeks to the experimental group. The control group was given empty capsule and normal diet. Animal weight and serum lithium levels were measured at the beginning of the experiment and were checked weekly. After four weeks, one third of the animal in each group were sacrificed and thyroid were examined to see the affect of drugs on them. Second group was sacrificed after one week of withdrawal and third group after two weeks of withdrawal. The serum lithium levels drop significantly after two weeks of withdrawal but did not reach the base line. There was significant increase in the weight of the animals, weight and relative tissue weight index of the thyroid, mostly due to congestion as hyperplasia and hypertrophy seen after two weeks of withdrawal had no significant increase as compared to the other experimental groups. Therefore, significant increase in weight of thyroid after two weeks of withdrawal can be attributed to persisting lithium in tissues or rebound phenomenon

Effect of lactation on postpartum uterine involution in rat

To see the effect of lactation on uterine involution. Setting: Postgraduate Medical Institute, Lahore. Design: Study of uterine weight and extracellular matrix in rat uterine wall. Subjects: Sixty six mature virgin albino rats. Average age 8 weeks. Average weight 156gms. Group A [non pregnant] 06 animals. Group B [postpartum lactating] 30 animals. Group C [postpartum non lactating] 30 animals. Six animals from group B and C each sacrificed daily from day 1-5 after parturition. Uterine weight increased 10-11 folds on first day after parturition [P <0.01]. The uterine wall was thickened. The collagen fibres were increased through out the uterine wall. They were surrounding groups of muscle fibres and individual myocytes also. Collagen degradation and removal resulted in uterine involution which was accelerated by lactation. Lactation accelerates the process of uterine involution

Role of zinc on lead induced nephrotoxicity in rat: a histological study

To determine the effects of lead and its interaction with zinc, lead acetate and zinc chloride was given alone and incombination to albino rats to study the histological changes in the kidneys. The animals were sacrificed after 7, 21 and 42 days. Lead exposed animals exhibited reduction in their body weight. There was degeneration and necrosis of PCT along with interstitial haemorrhage. These effects were minimized on administration of zinc during 7 days only this concluding a dose related protective effect of zinc on lead

Changes in extracellular matrix in rat uterine wall during pregnancy

To find changes in collagen fibers in extracellular matrix of uterine wall during early and late pregnancy. Settings: Postgraduate Medical Institute, Lahore. Design: Study of extracellular matrix in rat uterine wall. Subjects: Twenty four virgin mature albino rats. Average age 08 weeks. Average weight 155gms. Group A [non pregnant [06 animals. Group B [Pregnant] 18 animals, sacrificed after 1st, and 2nd and 3rd week of pregnancy. A significant rise in the uterine weight [without fetuses] during pregnancy was observed. During early pregnancy the collagen fibres were increased. Collagen degradation was noted during late pregnancy, which was correlated to increased amount of ground substance between the fibers. Thickness of uterine wall increased significant during early pregnancy but at full term it thinned out due to great stretching of the wall. During early pregnancy collagen fibres are increased in extracellular matrix of rat uterine wall, while, during late pregnancy they show degradation