Histochemical analysis of alcohol-lability and effects of inorganic ions on the metachromasia of galactogen.

Abstract

Galactogen localised in the albumen gland of a land snail exhibited an intense and selective metachromatic reaction with azure A at pH 3.5 to 5.5. The metachromasia was labile towards alcoholic treatment. Methanol, ethanol, n-propanol and n-butanol in this order abolished the metachromasia with increasing efficiency. An interesting relationship between the capacity to abolish the galactogen metachromasia and the dielectric constants of these alcoholic solvents was also observed. The higher the dielectric constant of an alcohol the lower was its capacity to suppress the metachromasia of galactogen. Inorganic ions also suppressed the metachromasia of galactogen. Their capacity to suppress the metachromasia was a linear function of the charge carried by them. The pH dependence, effects of alcohol treatment and inorganic ions on the metachromasia of galactogen are considered in comparison with that of sulfomucins, sialomucins and hyaluronic acid. The importance of metachromasia techniques in the histochemical detection of galactogen is described.