Morphological peculiarities of the pancreas of male rats after prolonged administration of monosodium glutamate during the recovery period

Abstract

The aim: To study changes in the exocrine and endocrine parts of the pancreas of rats after abolition of monosodium glutamate (MSG) administered in the diet. Materials and methods: White male laboratory rats with a baseline weight of 120 ± 5 g were randomized into 3 groups: 1 – control, 2 – animals with daily feeding of 70 mg/ kg MSG for 8 weeks, 3 – abolition of MSG with transfer of animals to a standard diet and pancreatic examination after 8 weeks. We used histological studies with morphometric analysis and statistical processing of acini and acinar cell areas, Langerhans islets, connective tissue (according to Stolte M.) and adipose tissue. Preparations of pancreas were stained with hematoxylin and eosin and azan. Results: The animals of groups 2 and 3 showed atrophic, degenerative and inflammatory disturbances in the exocrine and endocrine parts of the pancreas, which worsened after 8 weeks of MSG withdrawal (3 rd group). In the preparations, the Langerhans islets were of different shapes and sizes. Small islets predominated, as well as islets with low density of α- and β-cells, different capillary filling with blood and overgrowth of connective tissue in the capillary areas. The acinar cells and acini were reduced, and degenerative abnormalities were detected in the structures. Conclusions: After daily administration of 70 mg/kg MSG for 8 weeks, atrophic and degenerative changes in the exocrine and endocrine parts of the pancreas were revealed. No recovery of pancreatic structures was observed 8 weeks after MSG withdrawal.