大鼠中枢神经系统衰老的形态学研究—大鼠舌下神经逆行轴浆运输的年龄性变化

MORPHOLOGICAL STUDIES ON THE AGING CHANGES IN CENTRAL NERVOUS SYSTEM OF RAT---THE EFFECT OF AGING ON RETROGRADE AXONAL TRANSPORT IN HYPOGLOSSAL NERVE OF RATS

本文用HRP作为神经元标记的示踪剂,研究了不同年龄组大鼠舌下神经逆行轴浆运输的速度以及相同时间内不同年龄组大鼠舌下神经元中HRP的消逝程度。结果表明:随着大鼠的增龄,舌下神经中HRP逆行轴浆运输速度下降,在成年组为122.32mm/日,而老年组仅为73.34mm/日;同时,舌下神经元对HRP的清除能力也下降,在HRP标记细胞数达到最高峰后的60小时,幼年组舌下神经元对HRP的清除率为90%。成年组为87%,而老年组则降为68%。对上述发现所产生的衰老学方面的意义进行了探讨。

In 72 Wistar rats of the three age groups,Horseradish peroxidas(HRP)was injected unilaterally into the tongue to investigated the aging change of retrograde axonal transport in the hypoglossal nerve.After 3 to 72 hours,the animal were sacrificed by fixatives.Labelled neurons were observed and counted.The length of hypoglossal nerve in each rat was measured concomitantly to asses the velocity of retrograde axonal transport.As a result,we found that the velocity of retrograde axonal transport in hypoglossal nerve and the fade-rate of HRP in neuron decreased with age.The velocity in the adult group was 122.32mm/day but in the old group only 73.32mm/day.On the other hand,the fade of HRP were also changed with age.At 72 hours after injection.The fade-rate of HRP were 90% in the young group,87% in the adult group and only 68% in the old group. The presumptive roles and significance of the findings were discussed.