[Histochemical changes in the neurosecretory hypothalamic nuclei as result of an intoxication with mercury compounds...

The effect of experimental poisoning by organic compounds, frequently used in agriculture as fungicides, on the histochemical and histoenzymic pattern of the hypothalamic neurosecretory system has been studied. The experimental rats were fed by means of a gastric tube with the following compounds: Phenylmercuryacetate, 0.1 g daily, for 10 days; Aethylmercury-p-toluenesulphanilide, 0.2 g daily, for 10 days, and Methoxyethylmercurychloride (Ceresan), 0.1 g daily, for 6 days. The histochemical and histoenzymic investigations have shown that ingestion of Phenylmercuryacetate brought about an increase in the release of antidiuretic hormone (ADH) with a concomitant enhancement of production of neurosecretory substances. The peroral administration of Aethylmercury-p-toluenesulphanilide and of Methoxyethylmercury chloride instead, resulted in the accumulation of the neurosecretion within the hypothalamic-hypophyseal system with a parallel inhibition of ADH release. The experimental poisoning of Ceresan had also a stimulatory effect on the activity of many enzymes in the neurosecretory nuclei of the rat hypothalamus. Morphological changes resulting from the experimental intoxication were only rarely observed in the neurosecretory cells of the investigated hypothalamic nuclei.