PATHOGENETIC MECHANISMS OF VARIOUS SUBTYPES OF GESTATIONAL DIABETES MELLITUS IN PREGNANT RATS

The aim of the research. To determine the biochemical and morphological features of various GDM subtypes in pregnant rats.
Materials and methods. A prospective study was conducted on white nonlinear rats: 50 females and 15 males. After confirmation, female rats were divided into 3 groups: group I – 15 pregnant rats (control), group II – 12 pregnant rats (subtype model with pancreatic β-cell dysfunction); group III – 12 pregnant rats (subtype model with IR). All rats underwent determination of glucose, insulin, adiponectin, leptin, omentin, interleukin-6, C-peptide and C-reactive protein levels in venous blood, as well as histomorphological studies of pancreatic tissue.
Results. According to the data obtained, the subjects in group III were characterized by lower levels of adiponectin [245 (225; 290) ng/ml; p < 0,001], higher levels of leptin [8,45 (6,1; 12) ng/ml; p < 0,001] and C-reactive protein [1678 (1550; 1818 ng/ml; p < 0,001], and a high level of C-peptide was also detected [5448 (3852; 6861) pg/ml; p<0.001]. Histological examination of the endocrine part showed signs of fullness and expansion of the capillary walls, dystrophy of alpha cells, as well as swelling and detachment of cell groups from the capsule. For those studied in group II, a lower level of C-peptide was detected [1907 (1560; 2082) pg/ml; p = 0,01], which is typical for patients with pancreatic β-cell dysfunction. Histological examination revealed signs of deformation of the pancreatic lobules and necrobiotic changes both in the exocrine part of the organ and in the islets of Langerhans.
Conclusion. We characterized the biochemical and morphological features of various GDM subtypes in pregnant rats, which allowed us to form prospective pathogenetic models of these subtypes. The presented models can be used in scientific and then clinical practice to verify the pathogenetic subtype of GDM.

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