Samorajski T
J Am Geriatr Soc. 1976 Jan;24(1):4-11. doi: 10.1111/j.1532-5415.1976.tb03246.x.
The characteristic morphologic changes frequently observed in the brain of an old adult include a decrease in weight and volume, a change in the pattern of cerebral cortical convolutions, and an increase in ventricular size. Cell loss varies from region to region in the brain, and may be intensified in Alzheimer's disease and other disorders associated with senile dementia. Among the neuroglial cells, the microglia undergo the most significant changes with age. Although senile brain disease previously has been regarded as secondary to atherosclerosis, recent neuropathologic studies indicate that only 30 to 40 percent of senile brain disease arises from cerebrovascular pathologic lesions. The dilemma remains, however, of how much of the deterioration observed in the aged is related to disease and how much to senescence. The interaction between gene expression and environmental conditions in aging is another important question for the geriatrician. Progress in the control and treatment of disorders associated with old age depends upon further research into the mechanisms that underlie the process of aging in the brain.
在老年人脑中经常观察到的特征性形态学变化包括重量和体积减小、大脑皮质褶皱模式改变以及脑室大小增加。脑内不同区域的细胞损失情况各不相同，在阿尔茨海默病和其他与老年痴呆相关的疾病中可能会加剧。在神经胶质细胞中，小胶质细胞随年龄增长发生的变化最为显著。尽管老年脑疾病以前被认为是动脉粥样硬化的继发疾病，但最近的神经病理学研究表明，只有30%至40%的老年脑疾病源自脑血管病理病变。然而，一个难题仍然存在，即观察到的老年人脑功能衰退有多少与疾病有关，又有多少与衰老有关。基因表达与衰老过程中的环境条件之间的相互作用是老年医学专家面临的另一个重要问题。与老年相关疾病的控制和治疗进展取决于对大脑衰老过程潜在机制的进一步研究。
