EXPRESSION OF GLYCOSPHINGOLIPIDS IN SERUM-FREE PRIMARY CULTURES OF MOUSE KIDNEY-CELLS - MALE-FEMALE DIFFERENCES AND ANDROGEN SENSITIVITY

The expression of neutral glycosphingolipids was examined in primary k idney cell cultures derived from adult male and female beige mutant mi ce (C57BL/6J;bg'/bg') with enrichment for proximal tubule cells during preparation of explants and using defined serum-free medium for the c ulture conditions, Cells proliferated for 7 days in vitro to provide c onfluent or nearly confluent monolayers of epithelial-type growth indi cative of proximal tubule cells. The male vs female differences in neu tral glycosphingolipids seen in the kidney in vivo were retained in th ese 7 day cultures. Cultures derived from males contained galacto- and digalactosylceramides whereas those from females did not express thes e types of glycolipids. Also, male cells had higher ratios of sphingos ine: phytosphingosine containing species in Nfa (non-hydroxy fatty aci d) globotriaosylceramide and in glucosylceramide than females. The shi ft in sphingosine: phytosphingosine to male ratios in Nfa globotriaosy lceramide and in glucosylceramide could be stimulated in female kidney cells by treatment with 10(-5) M testosterone or 5 alpha-dihydrotesto sterone. The male-specific expression of neutral glycosphingolipids, t hen, appears to be stable character of male-type differentiation in mo use kidney that is passed on during proliferation in culture. Female k idney cells retain an ability to respond to androgens with specific ch anges in neutral glycosphingolipid expression during 7 days of growth in vitro in serum-free conditions, but do not respond with the inducti on of the male-specific glycolipids galacto- and digalactosylceramides as seen in vivo.