[The function of the cholinergic and sympathoadrenal systems in miners with long-term exposure to manganese oxides]

Long-term exposure to manganese oxides (MO) exceeding MPL leads at first to adaptation strain such as an increase in the activity of acetyl chlonesterase and correspondingly a decline in acetylcholine; greater excretion of catecholamin precursors with subsequent depletion of adaptive mechanisms. Under exposure to manganese concentration of 5.9 to 16.3 mg/m3, the adaptation exhaustion reactions in the sympathoadrenal system (SAS) and the cholinergic system (ChS) develop 7 to 9 years earlier than with 0.4-2.8 mg/m3 of MO. Moreover, ChS responds sooner than SAS to manganese exposure--about ten years earlier under high concentrations of manganese, 5-6 years earlier when being exposed to smaller concentrations. The above changes are believed to be the underlying reason why the nervous system pathologies should develop, with their incidence being at its greatest after thirteen and more- and twenty-one and more-year exposure to MO in concentrations exceeding MLP 19.5 to 54-fold and 1.3 to 9.3-fold respectively.