The anesthetic nitrous oxide affects dioxygen utilization by bovine heart and bean seed mitochondrial particles

Nitrous oxide affects dioxygen utilization by both bean seed and bovine heart submitochondrial particles when either succinate or reduced cytochrome c are used as substrates. Bovine heart particles exhibit reversible, dose-dependent partial inhibition of respiratory activity when exposed to N2O. Bean seed particle respiration is stimulated by low levels of N2O, but higher concentrations are inhibitory. These findings can be explained in terms of one locus of anesthetic action: cytochrome c oxidase, the terminal component of the mitochondrial respiratory chain. Alterations in respiration rates are expected to make important contributions to anesthesia in animals and to control of germination in plants.