Effect of the tripeptide Leu-Ile-Lys on the gastric mucosa in an experiment

Introduction. The high prevalence of gastric ulcer, as well as its multiple etiologies substantiate the urgency of developing new drugs effective in this condition. Previously, the antiulcer effect of the tripeptide Leu-Ile-Lys (LK-3) was revealed under experimental conditions in gastropathies of various origins. To clarify the mechanism of action of this compound, an in-depth experimental study of its effects on the gastric mucosa (GM) is necessary.

Aim. To study the effect of the tripeptide LK-3 on GM under experimental conditions.

Materials and methods . The experiment was performed on 16 Wistar rats. All animals were divided into two groups: the intact group and the group with intragastric administration of the tripeptide LK-3 (for 7 days, 11,5 mg/kg). Pathomorphological examination of the stomachs of experimental rats was performed. A histological picture of the GM was examined, and its thickness was measured. In addition, the density and composition of the inflammatory infiltrate, as well as the DNA replication index in the nuclei of cervical GM cells were determined.

Results . During gross and microscopic examination, no pathological changes in the GM were revealed in either experimental group. The tripeptide LK-3 administration caused a statistically significant increase in GM thickness, by 1,4 times, compared to the intact group. In addition, the DNA replication ratio in cervical GM cells in rats treated with LK-3 was 1,2 times higher than in intact animals. At the same time, 100% of the cells studied were in the S-phase of the cell cycle after administration of LK-3, compared to 75% in the intact group.

Conclusion. A 7-day intragastric administration of the tripeptide LK-3 (11,5 mg/kg) to rats caused an increase in GM thickness and in the proportion of cells in the S-phase of the cell cycle.

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