Some effects of vitamin A deficiency on the isolated rat lung alveolar type II cell.
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.
Department of Pediatrics, Human Oncology University of Wisconsin, Madison 53715.
R D
RD
Zachman
X
X
Chen
A K
AK
Verma
M A
MA
Grummer
D000818:Animals; D066298:In Vitro Techniques; D008297:Male; D010713:Phosphatidylcholines / Q000378:metabolism*; D011650:Pulmonary Alveoli / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011503:Transglutaminases / Q000378:metabolism*; D014212:Tretinoin / Q000378:metabolism*; D014801:Vitamin A / Q000378:metabolism*; D014802:Vitamin A Deficiency / Q000378:metabolism*
D010713:Phosphatidylcholines; D014801:Vitamin A; D014212:Tretinoin; D011503:Transglutaminases