The implication of gastrin as a trophic agent for colonic mucosa (CM) in arising and development of neoplasm in colon is undoubted. But its role in maintenance of the colonic epithelial transport function is almost not studied. The aim of the study was to examine the effect of omeprazole-induced (OM) hypergastrinemia (HG) of different terms on the colonic morphofunctional indices. Methods: Adult male Wistar rats were used under urethane anaesthesia according to a method of isolated colonic loop perfusing technique in vivo for determining of net water and electrolyte (Na⁺, K⁺, Cl^-) movements (Jnet). The 1^st studied group included animals (n = 20) receiving a vehicle (i.p.) for 1, 2, 3 and 4 weeks – baseline group (BG); the 2-5 groups (n = 27) – animals receiving OM (Dr.Reddy's, India) (14 mg/kg; i.p.) injections for 1-4 weeks respectively to induce HG. Plasma gastrin level (GL) was determined by radioimmunoassay. Mucosa thickness (MT), crypt depth (CD) and nuclear profound area of epitheliocytes (NPA) indices were measured. Results: Administration of OM for 1 week increased GL by 207.05% and decreased Jnet NaCl compared to BG. After 2 weeks of OM administration no significant changes of studied MFI were observed. Prolongation of OM influence up to 3 weeks entailed significant increase of GL by 131.10%, JnetCl^-, CD and MT and decrease of JnetNa⁺. HG for 4 weeks (GL increased by 189.27%) Jnet water, Na⁺ and NPA decreased and JnetCl^-, CD, MT increased significantly. Conclusions: The short-term OM-induced HG alters NaCl absorption. Prolongation of HG up to 3 weeks displays the trophic effect of gastrin on CM along with altered electrogenic JnetNa⁺ absorption. OM-induced HG for 4 weeks causes appearance of hyperplastic features and provokes decreasing of Jnet water and NaCl absorption.