nNOS protein and nitric oxide are increased in dko mice expressing a nNOS transgene.

<p>A. Overexpression of the nNOS transgene was confirmed by western blots for all mice assayed in the investigation. Upper panel shows a blot for nNOS in a representative nNOS TG+/dko muscle extract (Tg+) and a representative nNOS TG-/dko extract (TG-). Lower panel shows the same blot stained with Ponceau red prior to antibody labeling to confirm uniform loading of samples. B. Percent cytosolic nitric oxide (NO) in wild-type (white bar), nNOS TG-/dko (black bar) and nNOS TG+/dko (grey bar) muscle. n = 5 mice per group. Error bars represent standard error of the mean. * = significant difference as compared to wild-type. # = significant difference as compared to nNOS TG-/dko. p<0.05. C. Wild-type muscle showing NO present in the cytosol and highly concentrated at the sarcolemma. Bar = 50 µm. D. nNOS TG-/dko muscle exhibits low levels of NO in muscle fibers, but strong NO production by infiltrating mononuclear cells (arrow). E. Increased levels of NO are evident in the cytosol of muscle fibers from nNOS TG+/dko mice.