Bertoni-Freddari C, ZS-Nagy V, ZS-Nagy I, Pieri C
Aktuelle Gerontol. 1977 Jan;7(1):17-8.
Current hypotheses ascribe the role of pre-RNA storage or transport structures to the perichromatin granules. Their numerical density is directly related to the transcription activity of the nucleus. The perichromatin granules (P.K.) can be demonstrated in ultrathin sections with the stain used by Bernhard (1969) for ribonucleo-proteins. We have established the numerical density per unit of area in nuclear cross-sections of cells in young rats (1-2 months), old rats (26-29 months) and in relation to various cell function types. Cell aging causes a reduction in the numerical density of perichomatin granules in the big neurons of the cerebral cortex, the cerebellar granulocytes, the hepatocytes and the parotid cells. No age-related changes were found in the myocardial cells and erythroblasts of the same maturity. However, at the end of maturation, the number of perichromatin granules both in young and old erythroblasts was nil. (1) There is a quantitative reduction of perichromatin granules primarily in postmitotic and relatively postmitotic cells; (2) cell types showing no age-related reduction in perichromatin granules maintain high synthetic activity throughout their life; (3) the results confirm that relationships exist between numerical density of the perichromatin granules and cell activity; (4) the big fluctuations in the numbers of perichromatin granules in various cell types are probably connected with cell function.
目前的假说认为，染色质旁颗粒具有前体RNA储存或运输结构的作用。它们的数量密度与细胞核的转录活性直接相关。染色质旁颗粒（P.K.）可以在超薄切片中用伯恩哈德（1969年）用于核糖核蛋白的染色剂显示出来。我们已经确定了幼鼠（1 - 2个月）、老年大鼠（26 - 29个月）以及与各种细胞功能类型相关的细胞核横切面中每单位面积的数量密度。细胞衰老会导致大脑皮质大神经元、小脑粒细胞、肝细胞和腮腺细胞中染色质旁颗粒的数量密度降低。在相同成熟度的心肌细胞和红细胞母细胞中未发现与年龄相关的变化。然而，在成熟末期，年轻和老年红细胞母细胞中的染色质旁颗粒数量均为零。（1）染色质旁颗粒主要在有丝分裂后和相对有丝分裂后的细胞中出现数量减少；（2）染色质旁颗粒数量未显示出与年龄相关减少的细胞类型在其整个生命过程中保持高合成活性；（3）结果证实染色质旁颗粒的数量密度与细胞活性之间存在关联；（4）各种细胞类型中染色质旁颗粒数量的大幅波动可能与细胞功能有关。
