Table 3.

Synthesis and basolateral transport of C₆NBD-GlcCer and C₆-NBD-SM

	Percentage of total NBD lipid
	GlcCer	SM
Control	5.2 ± 0.7 (82.6 ± 5)	24.7 ± 6 (77.2 ± 6)
Cytochalasin D	4.7 ± 0.7 (82.0 ± 0.7)	22.4 ± 4 (74.1 ± 8)
Nocodazole	4.8 ± 0.9 (81.4 ± 3)	24.1 ± 5 (62.9 ± 6)

Cells were preincubated with or without 10 μg/ml cytD in HBSS at 37°C for 30 min or with 33 μM nocodazole for 2 h. Cells were then cooled and, in the presence or absence of the cytoskeletal drugs, incubated with 3 μM C₆-NBD-Cer as described in MATERIALS AND METHODS. Subsequently the cells were incubated at 37°C for 60 min in back-exchange medium and, after washing, scraped from the culture dish. The lipids were extracted from the back-exchange medium and the cells, and the NBD lipids were quantified as described in MATERIALS AND METHODS. In parentheses, the percentage of lipid transported to the basolateral plasma membrane is indicated. Values represent the data of three experiments ± SEM.