Coppola D M, Waguespack A M, Reems M R, Butman M L, Cherry J A
Department of Biology, Randolph-Macon College, Ashland, VA 23005, USA.
Histol Histopathol. 2006 May;21(5):487-501. doi: 10.14670/HH-21.487.
We have recently shown that unilateral naris occlusion (UNO) causes an increase in olfactory marker protein (OMP) immunoreactivity (IR) in mouse olfactory sensory neurons (OSN) from the occluded side of the nasal cavity and a decrease in OMP-IR on the non-occluded side, relative to controls. Given OMP's demonstrated role in olfactory modulation, these OMP-IR changes have been interpreted as a compensatory response by OSNs to odor deprivation on the occluded side and to supernormal exposure to odor on the non-occluded side of the nasal cavity. In the current study, we examined the developmental timing and the regional distribution of this process throughout the nasal cavity using immunocytochemistry. Results demonstrate that OMP-IR diverges in OSNs from the occluded side relative to the non-occluded side of the nasal cavity within eleven days after UNO, with statistically significant differences measurable after 17 days (n=16). We also measured relative levels of the Type 4 phosphodiesterase (PDE4A), another potential olfactory modulator, in nasal cavity tissue from UNO (n=8) and untreated mice (n=9) using western blots and immunocytochemistry. Like OMP, PDE4A-IR increased on the occluded side of the nasal cavity after UNO. Finally, we used immunocytochemistry to assess relative levels of olfactory-specific adenylyl cyclase (ACIII, n=4) and G-protein (Golf, n=2) in OSNs from the occluded and non-occluded sides of the nasal cavity of UNO mice. Following UNO, ACIII but not Golf -IR levels diverged comparing the occluded to the non-occluded sides of the nasal cavity. Taken together, our findings provide support for the previously unknown phenomenon of compensatory responses by OSNs to odor environment.
我们最近发现，单侧鼻孔闭塞（UNO）会导致小鼠鼻腔闭塞侧的嗅觉感觉神经元（OSN）中嗅觉标记蛋白（OMP）免疫反应性（IR）增加，而与对照组相比，非闭塞侧的OMP-IR则减少。鉴于OMP在嗅觉调节中已被证实的作用，这些OMP-IR变化被解释为OSN对鼻腔闭塞侧气味剥夺以及非闭塞侧气味超常暴露的一种代偿反应。在本研究中，我们使用免疫细胞化学方法研究了这一过程在整个鼻腔中的发育时间和区域分布。结果表明，在UNO后11天内，鼻腔闭塞侧的OSN中OMP-IR相对于非闭塞侧发生了分化，17天后可测量到统计学上的显著差异（n=16）。我们还使用蛋白质免疫印迹法和免疫细胞化学方法测量了来自UNO小鼠（n=8）和未处理小鼠（n=9）鼻腔组织中另一种潜在嗅觉调节剂4型磷酸二酯酶（PDE4A）的相对水平。与OMP一样，UNO后鼻腔闭塞侧的PDE4A-IR增加。最后，我们使用免疫细胞化学方法评估了UNO小鼠鼻腔闭塞侧和非闭塞侧OSN中嗅觉特异性腺苷酸环化酶（ACIII，n=4）和G蛋白（Golf，n=2）的相对水平。UNO后，比较鼻腔闭塞侧和非闭塞侧，ACIII的IR水平出现分化，但Golf没有。综上所述，我们的研究结果为OSN对气味环境的代偿反应这一先前未知的现象提供了支持。
