Sodium nitrite alone protects the brain microsomal Ca(2+)-ATPase against potassium cyanide-induced neurotoxicity in rats.

The effect of a short-term oral administration of potassium cyanide (KCN) (200 ppm in diet) with or without sodium nitrite (NaNO2) pretreatment on rat brain microsomal Ca2 +/- ATPase was investigated. The specific activity value of the enzyme significantly decreased (p < 0.05) by 50% compared with control and by 63% for KCN-treated rats compared with KCN-treated rats pretreated with NaNO2. There was no significant difference at the h = 0.05 level between the values obtained for the control and KCN-treated rats pretreated with NaNO2. These results show both that feeding lowers brain microsomal Ca(2+)-ATPase activity and that NaNO2 has a protective role (antidote function) in that respect.