VITAMIN-A-DEFICIENCY ALTERS RAT NEUTROPHIL FUNCTION

Previous studies showed a higher percentage of neutrophils from vitami n A deficient rats are hypersegmented and contain lower levels of cath epsin G than the neutrophils from control rats. In this study chemotax is, phagocytosis and oxidant generation were studied using either isol ated neutrophils or neutrophils in whole blood from four dietary group s of rats: 1) vitamin A deficient rats; 2) vitamin A deficient rats th at received vitamin A for 16, 8, 4 or 2 d prior to killing; 3) weight- matched rats pair-fed a vitamin A-complete diet; and 4) rats fed nonre stricted, vitamin A complete diet. Chemotaxis towards P. aeruginosa co nditioned medium and;formylated methinyl leucinyl phenylalanine was si gnificantly lower for neutrophils from vitamin A-deficient rats than f or neutrophils from weight-matched pair-fed rats, nonrestricted vitami n A sufficient rats and vitamin A deficient rats that received vitamin A for 16 d prior to killing. No differences in chemotaxis towards act ivated rat serum were noted among the neutrophils from the four groups of rats. Adhesion of P. aeruginosa organisms, phagocytosis of these o rganisms and generation of active oxidative molecules were significant ly lower in the neutrophils from the: vitamin A-deficient rats relativ e to these functions in the neutrophils from the vitamin A deficient r ats that received vitamin A for 16 d, weight-matched rats pair-fed a v itamin A complete diet; and rats fed nonrestricted, vitamin A-complete diet. Eight days after vitamin A administration to vitamin A deficien t rats, the ability of the neutrophils to phagocytose P. aeruginosa or ganisms and to generate active oxidant molecules was restored to the l evels observed for weight-matched, pair-fed rats and rats fed nonrestr icted, vitamin A complete diet. The elucidated alterations in neutroph il function in vitamin A deficient rats probably contribute to the alt ered ability of vitamin A deficient rats to fight infections.