Fig. 9

Effect of salt treatment on the insulin-mimetic activity of PIG-P in reconstituted adipocytes.

Isolated rat adipocytes were treated with 100 µg/ml trypsin and subsequently with 0.5 M NaCl, then supplemented with 200 µI of trypsin/salt extract (A and B, open and filled squares) or buffer (B, circles). After reconstitution, the cells were washed three times by flotation as described in the legend to Fig. 8 and then adjusted to 0.3 or 0.7 M NaCl or left without salt (A) or adjusted to increasing concentrations of NaCl (B). Subsequently, the adipocytes were washed twice by flotation (A) or left untreated (B). For one portion of cells, the salt treatment (0.7 M NaCl) was repeated (A). The cells were then assayed for stimulation of lipogenesis (A) or glucose transport (B) in the presence of increasing concentrations of PIG-P (A) or 5/mm PIG-P (B, filled squares) or absence of PIG-P (B, circles and open squares). Each point represents the mean ± SD of four adipocyte preparations and reconstitution reactions, with lipogenesis measurements in triplicate.