Histochemistry and Cytochemistry of Glycoproteins and Glycosaminoglycans

Abstract

One of the most intriguing areas of research in neurobiology is the role of carbohydrates in cell structure and function. Carbohydrates on macromolecules of neurons and glia are expected to play a role in cellular “recognition” and sorting out into histological arrangements (Barondes, 1970, 1975; Barbera et al., 1973; Hughes, 1973; Moscona, 1974; Roseman, 1974), synaptogenesis (Barondes, 1970; Vaughn et al., 1976, McLaughlin and Wood, 1977; Cotman and Taylor, 1974), myelination (Brady and Quarles, 1973; Wood and Engel, 1976), cell permeability (Rambourg, 1971), and cell immunity (Rambourg, 1971; Winzler, 1970). There is much interest and considerable research in each of these areas, but direct evidence linking carbohydrates in cellular macromolecules to specific functions of the nervous system is fragmented and incomplete. It may be that the serotonin receptor in brain is a carbohydrate (Wooley and Gommi, 1965; Vaccari et al., 1971), and there is evidence that the cholera toxin receptor involves a ganglioside (Cuatrecasas, 1973; Holmgren et al., 1973; Van Heyningen W. E., et al., 1971; Van Heyningen, S., 1974). The nicotinic acetylcholine receptor also contains carbohydrate (Meunier et al, 1974; Raftery et al., 1976; Salvaterra et al, 1977), as does acetylcholinesterase (Carlsen and Svensmark, 1970; Taylor et al, 1974; Wiedmer et al, 1974). The major glycoprotein of peripheral nerve myelin and a minor glycoprotein associated with central myelin are glyco-sylated (Quarles et al., 1973; Everly et al., 1973; Wood and Dawson, 1973). Several of the proteins of the isolated synaptic membrane are glycoproteins that may be isolated by adsorption onto lectin-matrix columns followed by elution with appropriate sugars (Gurd and Mahler, 1974; Zanetta etal., 1975).