老年性记忆减退大鼠内侧隔核-斜角带神经生长因子受体阳性神经元的改变

为探讨神经生长因子受体在老年性记忆减退大鼠记忆相关区域表达的改变，选用雄性ＳＤ 大鼠（青年组２０ 只，老年组４０ 只）进行Ｍｏｒｒｉｓ水迷宫行为学测定，老年组又分为老年记忆减退组（简称老年减退组）和老年记忆正常组（简称老年正常组）。分析内侧隔核－斜角带中神经生长因子受体表达的改变。老年减退鼠内侧隔核、斜角带垂直支和斜角带水平支三个核团神经生长因子受体阳性神经元的数量较老年正常组分别下降了３７．８９％ 、３９．７５％ 和３８．８６％ （Ｐ＜ ０．０１）。受试大鼠逃避潜伏期与内侧隔核－斜角带的神经生长因子受体阳性神经元数量呈负相关（内侧隔核ｒ＝ －０．８２３８，Ｐ＜ ０．０１；斜角带垂直支ｒ＝ －０．９０７６，Ｐ＜ ０．０１；斜角带水平支ｒ＝ －０．８１３８，Ｐ＜ ０．０１）。老年减退组神经生长因子受体阳性神经元灰度值较老年正常组三个核团分别下降３０．９１％ 、２９．６７％ 和３６．７１％ （Ｐ＜ ０．０１），胞体面积较老年正常组减少２９．０５％ 、１７．５２％ 和３７．８７％ （Ｐ＜ ０．０１）。老年减退组神经生长因子受体的丢失可能是引起老年性记忆减退的机制之一。

THE CHANGES OF NGFR IR NEURON IN SEPTUM MEDIALIS DIAGONAL BAND OF SENILE MEMORY DEFICIT RATS

For exploring the expression changes of nerve growth factor receptor(NGFR) in the septum medialis diagonal band(SM DB) of senile memory deficit rat(SMD), 60 male healthy SD rats, 20 young and 40 old, were tested with Morris water maze. The old was divided into SMD and senile memory normal rat(SMN). Qualitative and quantitative analysis of NGFR ir neurons were carried on three standard sections of SM DB. The NGFR ir neuron counts of SM, vDB and hDB in SMD rats were decreased by 37.89%, 39.75% and 38.86% compared with that of SMN (P<0.01). There was a negative correlation between the mean escape latency and the counts of NGFR ir neuron in SM DB of cxamined rats (SM r= 0.8238, P<0.01; vDB r = 0.9076, P<0.01; hDB r= 0.8138, P<0.01). Comparing with that of SMN the gray level of NGFR ir neurons in SMD rats were decreased by 30.91%, 29.67% and 36.71% (P<0.01), and somata area of SMD were reduced by 29.05%, 17.52% and 37.87% (P<0.01) than that of SMN (P<0.01). The results suggested losing of NGFR might be a mechanism of senile memory deficit. (Figures 1～9 on plate 59)