Distribution of heme oxygenase-2 in the brainstem nuclei of rats

An immunocytochemical method was used to study the distribution of neurons expressing heme oxygenase-2 (HO-2) in the nuclei of different parts of the brainstem in 16 male Wistar rats. Neuron sizes and cytoplasmic histochemical reaction product optical densities were determined in various nuclei. The nuclei of the medulla oblongata, pons, and midbrain were found to contain HO-2-positive neurons with different shapes, numbers, and sizes. HO-2-positive neurons were found 3-5 times more frequently in sensory nuclei than in motor nuclei. However, there were relatively large numbers of both sensory and motor nuclei in which HO-2-positive neurons were not seen or were identified only as occasional cells. © 2013 Springer Science+Business Media New York.