[Chronobiological characteristics of the cytological indicators of the islands of Langerhans in mice]. / Khronobiologicheskaia kharakteristika tsitologicheskikh pokazatelei insuliarnogo apparata podzheludochnoi zhelezy u myshei.

This experimental work was conducted on 40 sexually mature albino mice; with the aid of cytometry and cytochemistry the 24-hour rhythm of functional activity of beta-cells of the pancreas was shown. An enlargement of the nuclei and nucleoli of beta-cells, an accumulation of specific fuchsinophilic and zinc-containing granules was noted at night (10 p.m.--6 a.m.); this pointed to the high functional activity of the insular cells at this time. During the day (10 a.m.--6 p.m.) the volume of the nuclei and nucleoli proved to decrease, and the specific granularity of beta-cells became less pronounced. Circadian rhythmicity of the insulin production by beta-cells was also indicated by the changed count of the insulin-containing blood erythrocytes.