title: [Effect of long-term thyroxine administration on the endocrine epithelium of rat pancreas].
abstract: The effect of prolonged thyroxine administration (0.001 mg/g BW) on pancreatic islets has been studied on 64 Wistar male rats by means of radioautographic, morphometric and electron microscopic methods. The phase response in the amount of the DNA-synthesising cells of the middle class islets has been revealed: the initial increase (5 days) is followed by a decrease (30 days) and then by a return to the control levels (60 days). The level of metabolism in sulphur-containing proteins has decreased in both A- and B-cells. After 30 days of the experiment, B/A cell volume ratio has been shown to increase. Electron microscopic studies have revealed ultrastructural reorganization of B-cells from "resting" B-cells into "dark" B-cells at increased excretion of secretory material.
mesh_terms: D000818:Animals; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D004848:Epithelium / Q000648:ultrastructure; D007515:Islets of Langerhans / Q000166:cytology / Q000187:drug effects* / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D051381:Rats; D013974:Thyroxine / Q000494:pharmacology*
chemical_list: D013974:Thyroxine
vernacular_title: Vliianie dlitel'nogo vvedeniia tiroksina na éndokrinnyĭ épitelii podzheludochnoĭ zhelezy krys.