Reduction of tetrazolium salts by malarial parasites

Free and intraerythrocytic forms of Plasmodium berghei and P. knowlesi reduced tetrazolium salts to their colored formazans when these cells were incubated with TZ under anaerobic conditions. Mepacrine hydrochloride incubated with P. berghei in vitro inhibited tetrazolium reduction. Plasmodia from mepacrine-treated hamsters had an impaired capacity to reduce TZ salts.