Microscopical study on the age related changes in the adrenal gland of male albino rat

In this work, twenty-four male albino rats were studied at [5-6] months of age [adult group] and at [23-24] months [aged group]. Light microscopic examination of aged animals revealed degenerative changes in some cells of zona fasciculata together with mononuclear cellular infiltration. Areas of necrosis were detected in zona fasciculata of some animals. Dilatation and congestion of sinusoidal capillaries were seen in zona fasciculata. Nodule like structures were detected among the cells of zona fasciculata of some animals. Marked increase in ascorbic acid and lipid contents was detected in inner cortical zone. In adrenal medulla, there was an apparent decrease in the number of norepinephrine secreting cells. Morphometric study revealed a significant increase in the mean thickness of zona fasciculata of the aged animals. Ultrastructural study showed that some cells of zona fasciculata of the aged animals had irregular nuclei. Disruption and loss of inner mitochondrial structure were seen in some zona fasciculata cells. In adrenal medulla, norepinephrine secreting cells showed degenerative change with decrease in the number of secretory granules

Light and electron microscopic study on the effect of aluminium hydroxide and the possible protective role of calcium carbonate on the lung of albino rat

While aluminium is not a heavy metal, it was found to be toxic. This study was conducted to show the effect of aluminium hydroxide on the lung and the effect of concomitant administration of calcium carbonate. Thirty rats were used and divided into three groups, ten animals each. Group I, [control group], Group II included rats which received intraperitoneal injection of 80 mg/ kg body weight aluminium hydroxide, 3 times per week for 2 months, Group III included rats which received aluminium hydroxide in the same dose, in addition the animals received 150 mg calcium carbonate daily orally for 2 months. At the end of experiment, the lung was excised and processed for both light and electron microscopic study. Light microscopic examination of [Group II] revealed focal exfoliation of the lining epithelium of the airway passages with cellular infiltration around the bronchi and in interstitium of the lung. Intraalveolar hemorrhage was observed as well as thickening of interalveolar septa. Excessive deposition of collagen fibers in the lung interstistium was noticed. Fragmentation and decrease of elastic fibers were seen. Apparent increase in the number of goblet cells in the wall of bronchi was detected. Electron microscopic examination of [group II] animals revealed the presence of numerous pneumocytes type II. Some of them had degenerated cytoplasm. The interalveolar septum showed great number of eosinophils and neutrophils together with collagen fibers deposition. Whereas, concomitant administration of calcium carbonate caused partial amelioration of aluminium induced lung toxicity

histological study of experimentally induced allergic encephalomyelitis in the guinea pig

Experimental allergic encephalomyelitis [EAE] is a neuroimmune disease. It was induced in the guinea pigs by intradermal injections of the guinea pig spinal cord in an emulsion with complete Freund's adjuvant. In order to study that model twenty guinea pigs were used. They were divided equally into 2 groups, group I [control group] and group [II] in which the [EAE] was induced. Sections of the lumbar segments of the spinal cord, the brain stem and the cerebellar cortex were taken. The severity of the [EAE] lesions varied from one place to the other. The present study showed mononuclear cellular infiltration of the lumbar segment of the spinal cord. Motor neurons of the spinal cord showed degenerative changes. Some neurons had shrunken cell body with deeply stained eccentric nuclei and their cytoplasm showed chromatolysis. Other neurones had large cell bodies. In some motor cells the nuclei couldn't be detected. An area of complete degeneration of the neural element was detected in the gray matter of the spinal cord. The glial elements showed proliferative change. In the brain stem, there was a subpial cellular infiltration. The polygonal nerve cells of the brain stem showed degenerative changes. Also the nerve fibers of the brain stem were affected in the form of beading, interruption with area of marked thinning. Degenerative changes were seen in the purkinje cells and granular cells of the cerebellar cortex. Some of the purkinje cells had small deeply stained pyknotic nuclei. Other cells showed fragmented nuclei. The nuclei of some granular cells in the granular layer became deeply stained