The protective effect of sodium nitroprusside (SNP) treatment on Arabidopsis thaliana seedlings exposed to toxic level of Pb is not linked to avoidance of Pb uptake.

The effects of 100 μM Pb(NO₃)₂ on 7-day-old Arabidopsis thaliana seedlings grown from seeds pretreated with a nitric oxide donor, sodium nitroprusside (SNP), or a nitric oxide scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) were investigated. Physiological stress induced by Pb (reduced root growth) was less evident in seedlings grown from seeds pretreated with SNP. However, SNP pretreatment of seeds did not affect Pb accumulation in the seedlings.