Meeting Abstract

P1.113  Thursday, Jan. 3  Effects of p-Aminosalicylic Acid on the Neurotoxicity of Manganese on Biogenic Amines in the Nervous System and Innervated Organs of Crassostrea virginica KING, C.*; MYRTHIL, M.; CARROLL, M.A.; CATAPANE, E.J.; Medgar Evers College; Medgar Evers College; Medgar Evers College; Medgar Evers College catapane@mec.cuny.edu

Manganese is a neurotoxin causing Manganism in individuals exposed to high airborne levels. Exposure to high levels for long periods causes mental and emotional disturbances, and slow and clumsy body movements. Manganese injures dopamine neurons involved in control of body movements. Recently, p-aminosalicylic acid (PAS) is being used to alleviate symptoms of Manganism, but its mechanism of action is unknown. Crassostrea virginica, possesses a dopaminergic innervation of its gill. We reported manganese caused reductions of dopamine in the cerebral and visceral ganglia and gill, but not norepinephrine, octopamine or serotonin. Those results are consistent with reported mechanisms of action of manganese in human and mammalian systems. We now studied the effects of PAS on manganese toxicity in the animal. C. virginica were exposed to 0.5 and 1 mM of manganese with and without 0.5 and 1 mM of PAS by removing one shell and maintaining the animals in individual containers of aerated artificial sea water at 18°C for 3 days. Controls were similarly treated without manganese or PAS. Amines were measured by HPLC with fluorescence detection. PAS protected the ganglia and gill against the effects of 0.5 mM manganese, but not against the 1 mM manganese treatments. We did not see similar results for serotonin levels. The study demonstrates PAS can protect against the neurotoxic effects of manganese, but is concentration dependent. These findings may provide insights into the actions of PAS in treatments of Manganism. This work was supported by grants 2R25GM06003-05 of the Bridge Program of NIGMS, 0516041071 of NYSDOE, 0622197 of the DUE Program of NSF, 0420359 of the MRI Program of NSF and 67876-0036 of PSC-CUNY.