NOS expression. A. Micrographs showing the expression of nitric oxide synthase (NOS) in pyramidal neurons of representative examples of (from left): an uninfected mouse, an untreated Plasmodium berghei-infected mouse (inf.), and a P. berghei-infected mouse treated with Azadirachta indica crude extract. B. Effect of A. indica on the expression of NOS in pyramidal neurons of P. berghei-infected mice. Note the significant decrease in expression following treatment with chloroquine, artemether, and A. indica extract highest dose. Data are mean ± SEM.