NADPH diaphorase staining within the developing olfactory bulbs of normal and unilaterally odor-deprived rats.

Littermate rat pups underwent either unilateral surgical occlusion of the right external naris or sham surgery on postnatal day 1. At 10, 20 or 30 days postpartum olfactory bulbs were sectioned and stained using nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry. Two types of staining were observed and analyzed. The reaction produced a Golgi-like filling of short-axon cells in both deep and superficial bulb areas. No differences in the number, morphology or distribution of these cells were found either across ages or treatment conditions, indicating that the cells are resistant to the effects of the deprivation paradigm. Large regional variations in glomerular and olfactory nerve layer staining density were also observed at each age, reinforcing notions of functional or structural differences between glomeruli at very early ages.