The morphological and histochemical neurosecretory magnocellular system in the rat after administration of chlorpromazine.

The effect of chlorpromazine (CPZ) on the neurosecretory action of the hypothalamo- hypophyseal system was investigated in 72 male rats. The experimental animals received CPZ in a dose of 0.4 mg, 4.0 mg and 20.0 mg/kg b.w. for 30 days. The rats were sacrificed by decapitation at 24 h and 7 days after the last dose of the drug. The neurosecretory material was stained with paraldehyde fuchsin in the supraoptic nucleus, paraventricular nucleus, eminentia mediana and neurohypophysis, the tigroid was stained with toluidine blue and the acid phosphatase activity was evaluated histoenzymatically. It was found that CPZ reduced the content of the neurosecretory material after 24 h, while an increase was observed 7 days after the last drug administration.

Dactinomycin-induced veno-occlusive disease in rats. The hepatoprotective action of amifostine. Evaluation in a light and electron microscope.

The purpose of the study was to draw upan experimental model of hepatic veno-occlusive disease (VOD) induced by dactinomycin (ACT) and to investigate the possible hepatoprotective effects of Ethyol (amifostine). Pathological changes corresponding to a VOD picture of varying intensification were found in the liver samples obtained from all the rats receiving ACT. Amifostine appears to act protectively to liver changes caused by dactinomycin.

A preliminary evaluation of thyroid and respiratory tract neuroendocrine cells in the rat after experimental hypercalcaemia.

The goal of this study was to investigate the influence of experimentally induced hypercalcaemia (after 100000 UI Vigantol and CaCl2) on neuroendocrine cells (NECs) in the thyroid and airways in the rat. After 24 h, 7 days and 14 days the thyroid and lungs were collected. Paraffin sections were immunocytochemically stained with specific antibodies against CGRP, calcitonin (CT) and synaptophysin (SY) in the airway NECs and thyroid C cells. The largest hypercalcaemia were observed in experimental rats after 7 days. More significant changes in the number and size of neuroendocrine cells were observed in the thyroid gland as well as in the airways. In the airways only a slight increase in the number of neuroepithelial bodies (NEBs) was observed, some of which gave evidence of hypertrophy symptoms.

Effects of CP 55,940--agonist of CB1 cannabinoid receptors on ghrelin and somatostatin producing cells in the rat pancreas.

Cannabinoids participate in the modulation of numerous functions in the human organism, increasing the sense of hunger, affecting carbohydrate and lipid metabolism, and controlling systemic energy balance mechanisms. Moreover, they influence the endocrine system functions, acting via two types of receptors, CB1 and CB2. The aim of the present study was to examine the number, distribution and activity of ghrelin and somatostatin producing endocrine cells in the pancreas of rats after a single administration of selective CP 55,940 agonist of CB1 receptor. The study was performed on 20 rats. Neuroendocrine cells were identified by immunohistochemical reactions, involving specific antibodies against ghrelin and somatostatin. The distribution and number of ghrelin- and somatostatin-immunoreactive cells were separately studied in five pancreas islets of each section. A performed analysis showed a decreased number of somatostatin-immunoreactive cells and a weak immunoreactivity of ghrelin and somatostatin containing neuroendocrine cells in the pancreatic islets of experimental rats, compared to control animals. The obtained results suggest that a single administration of a selective CP 55,940 agonist of CB1 receptor influences the immunoreactivity of endocrine cells with ghrelin and somatostatin expression in the pancreas islets.