CELL-SPECIFIC EFFECTS OF LEAD ON CULTURED NEURONS OF THE FRESH-WATER SNAIL PLANORBARIUS-CORNEUS

Cultures of isolated neuronal populations from the central ganglia of the gastropod mollusc Planorbarius corneus were used for testing the e ffects of inorganic lead. The examined parameters were cell survival, neurite outgrowth and cytoskeletal morphology. In large heterogeneous neuronal populations as obtained from a whole cerebral or pedal gangli on, the different sensitivity to lead is reflected mainly on the cell survival. The neurons belonging to the homogeneous E cluster populatio n are more sensitive; in fact a higher percentage of them do not survi ve in the presence of lead. Moreover, in this neuronal cell type the n eurite outgrowth is dramatically affected by lead only when the neuron s are cultured on conditioned substrate. Possibly, membrane mechanisms activated for the neurite outgrowth represent a target for inorganic lead. The few neurites sprouted in presence of lead do not evidence ch anges in the cytoskeletal components.