Neuroscience Research Program, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia; University of New South Wales, New South Wales, Australia.
J Neurosci Res. 2012 Jun;90(6):1126-35. doi: 10.1002/jnr.23008. Epub 2012 Feb 22.
Neuropeptide Y (NPY) and peptide YY (PYY) are differentially expressed throughout the olfactory neuroepithelium (ON), with NPY expression present in sustentacular cells, olfactory ensheathing cells, and olfactory receptor neurons and PYY expressed only in sustentacular cells. Examination of the anatomical morphology of the ON in NPY knockout (NPY⁻/⁻) and PYY knockout (PYY⁻/⁻) mice shows that there are significantly more neurons in PYY⁻/⁻ mice and significantly fewer neurons in NPY⁻/⁻ mice. Interestingly, the mature neurons of NPY⁻/⁻ mice were undergoing apoptosis. The transcription factor Mash1, which is critical in the production of olfactory precursors, is also differentially expressed in NPY⁻/⁻ and PYY⁻/⁻ ON. It is upregulated in the neurons of NPY⁻/⁻ mice and unchanged in PYY⁻/⁻ mice. Furthermore, significantly fewer olfactory neurospheres are present in cultures prepared from PYY⁻/⁻ mice in the first 2 weeks compared with NPY⁻/⁻ and wild-type mice. Together these results suggest that, during olfactory neurogenesis, NPY acts as a trophic factor for the maturation and survival of olfactory receptor neurons, whereas PYY has an important role in the regulation of olfactory neuron differentiation.
神经肽 Y（NPY）和肽 YY（PYY）在整个嗅神经上皮（ON）中呈现差异表达，其中 NPY 表达存在于支持细胞、嗅鞘细胞和嗅觉受体神经元中，而 PYY 仅表达于支持细胞中。对 NPY 敲除（NPY⁻/⁻）和 PYY 敲除（PYY⁻/⁻）小鼠的 ON 解剖形态学进行检查发现，PYY⁻/⁻小鼠中的神经元数量明显更多，而 NPY⁻/⁻小鼠中的神经元数量明显更少。有趣的是，NPY⁻/⁻小鼠的成熟神经元正在经历细胞凋亡。转录因子 Mash1 对于嗅觉前体细胞的产生至关重要，其在 NPY⁻/⁻和 PYY⁻/⁻ON 中的表达也存在差异。它在 NPY⁻/⁻小鼠的神经元中上调，而在 PYY⁻/⁻小鼠中不变。此外，与 NPY⁻/⁻和野生型小鼠相比，从 PYY⁻/⁻小鼠制备的培养物中，神经球的数量在最初的 2 周内明显减少。这些结果共同表明，在嗅觉神经发生过程中，NPY 作为一种营养因子，对于嗅觉受体神经元的成熟和存活具有重要作用，而 PYY 则在调节嗅觉神经元分化方面发挥着重要作用。
