MEMBRANE CARBOHYDRATE CONJUGATES DESIALYLATION DOES NOT ALTER [H-3]-DOPAMINE UPTAKE IN RAT STRIATAL SLICES

Incubation of rat striatal slices induced a large decrease (about 50%) of DA uptake and a slight desialylation of polysialogangliosides (GT1 b, GD1b, GD1a) with an increase of monosialogangliosides (GM1). Moreov er, a pretreatment of slices by exogenous added neuraminidase of Vibri o cholerae did not modify DA uptake, although the pattern of gangliosi des was modified and there was considerable loss (about 45%) of sialic acid in gangliosides and glycoproteins. It was verified that neuramin idase activity occured in synaptic membrane. Thus, DA uptake was appar ently not altered by desialylation of plasma membrane carbohydrate con jugates. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.