Age-Related Changes in P2 Odorant Receptor Mapping in the Olfactory Bulb
Age-Related Changes in P2 Odorant Receptor Mapping in the Olfactory Bulb
复制标题
DOI：
10.1093/chemse/bjq029
复制
发表时间：
2010-06-01
期刊：
影响因子：
3.5
通讯作者：
Kobayashi, Masayoshi
中科院分区：
文献类型：
--
作者：
Costanzo, Richard M.;Kobayashi, Masayoshi
识别气味的能力依赖于气味受体在嗅球内固定位置上的空间映射。在老年人中，气味识别和辨别往往受损。本研究的目的是确定是否有年龄相关的气味受体映射的变化。我们研究了8组年龄从2周到2.5岁不等的小鼠，并将P2气味受体投射到嗅球内侧和外侧区域内的目标肾小球上。总共60只小鼠用于测量P2肾小球的数量、球长度、每个肾小球的位置以及靶向每个肾小球的P2轴突的量。我们发现，超过70%的嗅球含有多个P2肾小球，球长度增加42%之间的年龄2和13周，和P2肾小球的位置转移与球的生长。在大多数情况下，靶向肾小球完全或部分充满P2轴突。在某些情况下，靶向是弥漫性的，肾小球仅接收少数杂散的P2标记的轴突。在3-6月龄的成年小鼠中，弥漫性靶向的频率很少（< 4%）。然而，在老年小鼠中观察到弥散靶向的显著增加，在1岁时达到10%，在2岁时达到22%。这些发现表明，气味受体映射在老年时变得更加混乱，并可能导致老年人嗅觉功能受损。
The ability to identify odors is dependent on the spatial mapping of odorant receptors onto fixed positions within the olfactory bulb. In elderly adults, odor identification and discrimination is often impaired. The objective of this study was to determine if there are age-related changes in odorant receptor mapping. We studied 8 groups of mice ranging in age from 2 weeks to 2.5 years and mapped the projection of P2 odorant receptors onto targeted glomeruli within medial and lateral domains of the olfactory bulb. A total of 60 mice were used to measure the number of P2 glomeruli, bulb length, the position of each glomerulus, and the amount of P2 axons targeting each glomerulus. We found that over 70% of olfactory bulbs contained multiple P2 glomeruli, bulb length increased 42% between the ages of 2 and 13 weeks, and the position of P2 glomeruli shifted with bulb growth. In most cases, targeted glomeruli were either completely or partially filled with P2 axons. In some cases, targeting was diffuse, with glomeruli receiving only a few stray P2-labeled axons. The frequency of diffuse targeting was rare (< 4%) in adult mice 3-6 months in age. However, significant increases in diffuse targeting were observed in older mice, reaching 10% at 1 year and 22% at 2 years of age. These findings suggest that odorant receptor mapping becomes more disrupted in old age and could account for impaired olfactory function in elderly adults.