[Changes in the human amygdaloid complex due to age].

The normal aging process of the amygdala was studied in 35 human (male) brains. They were selected according the following criteria: 1) neither the clinical history nor the macro and microexamination of the brains should point out alterations of the CNS non age-dependent; 2) time elapsed between decease and brain fixation should be inferior to 16 hours (the mean was 6 hours); 3) age of patients should be uniformly distributed between 14 and 86 years (at least 4 brains per decade). The brains were fixed in buffered formalin (10%) and processed for paraffin embedding. The blocks containing the amygdaloid complex were coronal and serially sectioned (7 microns) and stained alternatively by Nissl, PAS or hemltoxylin-eosin. The changes studied in the amygdaloid complex were: number of neurons and karyometry. The numerical values obtained in this study were statistically analyzed. The neuronal loss ranged between 36 and 47% (p less than 0.001) according the nuclei. The nuclear size followed 3 periods: first (till the age of 45 years) atrophy (between 19 and 39%, p less than 0.01); second phase from 45 to 75 years, hypertrophy (between 13 and 28%, p less than 0.01); and a third phase that showed a slight size reduction of the nuclei.