ALTERATION OF THE MORPHOLOGY AND NEUROCHEMISTRY OF THE DEVELOPING MAMMALIAN NERVOUS-SYSTEM BY HYDROGEN-SULFIDE

1. Hydrogen sulphide (H2S) is a broad spectrum toxicant that occurs wi dely in nature and is also released by a variety of industrial activit ies and processes. 2. The central nervous system (CNS) appears to be t he major target organ. 3. There is great potential for insult or injur y to the developing or immature CNS. 4. The risks of chronic or repeat ed exposures to low concentrations have not been well defined. 5. Expo sure to low concentrations of H2S to time-pregnant rats from day 5 pos tcoitus until day 21 postnatal results in architectural modification o f cerebellar Purkinje cells, alteration of putative amino acid neurotr ansmitters and changes in monoamine levels in the developing rat brain up to day 21 postnatal. 6. H2S-induced alterations in monoamine tissu e levels observed ih the developing rat brain return to control values if exposure is discontinued during development, that is, at day 21 po stnatal.