Some effects of vitamin A deficiency on the isolated rat lung alveolar type II cell
1992
Zachman, R.D. | Chen, X.M. | Verma, A.K. | Grummer, M.A.
Alveolar Type II cells were isolated from control and vitamin a deficient rats and allowed to form a monolayer in plastic dishes for 16-18 hours. The vitamin A content (retinol plus retinyl palmitate) of deficient cells was 50-75% less than in control cells on a per mg protein basis. Isolated Type II cells took up [3H]-retinol, synthesized [3H]-retinyl palmitate, and after 4 hours, 24% of the radioactivity in the Type II cells was [3H]-retinoic acid. Deficiency did not appear to alter retinoic acid synthesis. Phosphatidylcholine (PC) and disaturated phosphatidylcholine (DSPC) synthesis, were slightly less in deficient cells compared to control (95 and 85% respectively). In addition, 10(-6) M and 10(-5) M retinoic acid in the reaction media stimulated both PC and DSPC synthesis by 120-140% in control cells. The stimulating effect of retinoic acid was present in deficient cells as well, but less pronounced (120% with 10(-5) M). Vitamin A deficient Type II cells also had less basal levels of both tissue transglutaminase and epidermal transglutaminase activity than control cells.
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