The interaction of bisulfite and its free radical analog-nitroxyldisulfonate with periodic acid-oxidized lymphocytes and their effect on blastogenesis

Nitroxyldisulfonate [Fremy's salt; (KSO₃)₂NO] and bisulfite (NaHSO₃) have abolished periodic acid (H₅IO₆)-induced blastogenesis of human peripheral blood lymphocytes (HPBL), but only inhibited the blastogenic response of H₅IO₆-oxidized rat and mouse lymphocytes, as determined by the rates of nucleic acids synthesis, BrdUrd incorporation and by cell numbers in S + G₂ + M phases of the cell cycle. The viability of the intact human, rat and mouse lymphocytes remained essentially unimpaired by 30 min pulses of 1 mM Fremy's salt or bisulfite. The marked inhibition of periodic acidinduced blastogenesis, exerted by Fremy's salt and by bisulfite, was attributed to the effect of the corresponding carbonyl addition derivatives formed in situ of the oxidized cell membranes. Consequently, it is concluded that Fremy's salt like bisulfite possibly forms addition derivatives with membrane carbonyls of viable target cells.