The grelin blood level was measured on 54 patients, of whom 18 were healthy volunteers; 20 patients with cholecystolithiasis had been measured perioperatively during the cholecystectomy; and the rest 16 patients of the study group had had cholecystectomy 2-15 years ago. All patients demonstrated perioperative hypergrelinemy with the normalization of the grelin level during the long-term follow-up. Grelin is considered to have certain immunomodulating and anti-inflammatory effects, thus improving the postoperative regeneration. Therefore, the increase of grelin blood level during the perioperative period is considered to be a defense reaction.