TDK conference 2017

Equine gastric ulcer syndrome is a common clinical entity and proton-pump inhibitors (omeprazol) are considered as the choice of treatment. Omeprazol, by inhibiting gastric parietal cell H+/K+ ATPase, leads to achlorhydria and secondary decreased intestinal calcium absorption; and long-term use is associated with an increased risk of osteoporosis in men.

We hypothesized that the 28-day long enteric coated omeprazol treatment decreases the serum calcium, phosphate, calcitonin and increases the serum PTH and D-hormone concentration while decreases the fractional clearance of calcium.

Horses underwent physical examination, gastroscopy, routine hematology and serum biochemistry prior to enrollment of the study. Twelve healthy horses were randomly assigned to either treatment or placebo group. Blood and urine were collected at day 0, 14 and 28 of the study. Variables of interest included serum Ca, K, Na, P, Mg, calcitonin, D-hormone and PTH; urine Ca, K, Mg, Na, P concentration and their fractional clearance. Data was analyzed by two-way repeated measures ANOVA with the Bonferroni post-hoc test. P< 0.05 was considered significant.

We found that the serum electrolytes, calcitonin, D-hormone and PTH did not change significantly between the groups during the study (P>0.05). The concentration of urine Ca and P decreased compared to the placebo group (P=0.001 and P<0.02, respectively). The fractional clearance of potassium increased (P=0.02), while calcium’s (P=0.008) decreased compared to the placebo group.

Enteric coated omeprazol administered in the standard therapeutic dose for 28 days altered the electrolyte homeostasis, however the magnitude of the changes on the serum electrolytes and hormones were not significant.