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Purified intestinal brush border membrane (BBMV) was prepared from 8wk-old pigs with an average weight of 50㎏. The isolation procedure of porcine BBMV included magnesium precipitation, differential centrifugation, and sucrose density gradients with ultracentrifugation. The degrees of purification of BBMV were checked by the enrichments of specific activities of ALP and sucrase. The degrees of contamination from other cellular organelles were evaluated by the enrichments of Na^+/K^+ ATPase, LDH, cytochrome c oxidase, cytochrome c reductase, and ACP. The BBMV fraction was enriched 16.0 fold in ALP and 16.3 fold in sucrase over the cellular homogenate. The minimal enrichments of other marker enzymes observed here indicated minimal contamination with other cellular organelles. Uptake of D-[³H] -glucose in Na^+ dependent with BBMV exhibited the pattern of carrier mediated transport. The average apparent. K_m and V_(max) values for Na^+ dependent transport of glucose from pigs were 1.16 mM and 17.4 pmoles/㎎ protein/㎎/min, respectively. Uptake of glucose by Na^+ dependent transport by isolated BBMW was completely inhibited in the presence of phloridizin, indicating that isolation of BBMV in the bilayer membrane was well characterized. In conclusion, our isolation procedure yielded well purified BBMV and isolated BBMV exhibited Na^+ dependent glucose transport as an indictive of the nature of vesicles.
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