ArticleOdorant Threshold Following Methyl Bromide-Induced Lesions of the Olfactory Epithelium
Section snippets
Subjects
Eight adult male Long–Evans hooded rats (250–300-g body weight) were housed individually in a temperature- and humidity-controlled vivarium. Throughout the course of all training and testing, the animals were maintained on a food restriction schedule such that their body weight was reduced to 80% of free-feeding levels. The food restriction schedule was sufficient to produce the necessary motivation for the behavioral task. This and all other animal experimentation were conducted in accordance
Control Tests and Prelesioned Performance
Prior to threshold testing, the animals were given “no cues” tests in which no odorant was present over 10 blocks of 20 trials. These control tests were given to ensure that air/odorant discrimination behavior was based upon olfactory cues and not some other extraneous stimuli (e.g., auditory cues from the various valves or flow cues). When these tests were given, all animals performed at near-chance levels (50%).
The mean and standard deviation of detectability for each of the eight animals
Discussion
Exposure to MeBr resulted in extensive damage to the OE, rendering aneuronal greater than 95% of the epithelium on average, in keeping with our previous report detailing the anatomical consequences of MeBr exposure [39]. In accordance with the epithelial damage, other experiments not presented here demonstrate that almost all glomeruli lack any detectable anterogradely transported label at this time after lesion (35, 36and manuscript in preparation). Nonetheless, the damage did not prevent the
Acknowledgements
This work was supported by NIH Grants P01 DC 00220 K04 DC 00080. We thank Renee Mezza for her excellent technical assistance and Dr. George Ring for his photographic expertise. We also thank Dr. Frank Margolis for his generosity in supplying us with anti-OMP antiserum.
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