[Dynamics of leptin plasma levels after abdominal surgical procedures]

In addition to its basic role as regulator of the amount of body fat and food intake leptin plays a part also as an acute phase reactant. A rise of the leptin level during this period may be associated with anorexia and cachexia in relation to general inflammatory manifestations. The objective of the present study was to characterize the dynamics of the leptin concentration in patients after intraabdominal surgery.

The prospective study was implemented in a group of 16 men subjected to planned surgery--resection of colorectal carcinoma. The plasma leptin concentration (RIA), TNF alpha, IL-beta. IL-6, sIL-2R (ELISA), CRP, alpha-1-antitrypsin, alpha-1-acid glycoprotein and ceruloplasmin (nephelometry) were assessed before surgery and then +24, +48 and +72 hours after the beginning of the operation and compared with concentrations in healthy subjects.

Plasma leptin concentrations culminate +24 hours after surgery and in this stage they do not correlate with the BMI. Within 48 hours the concentration reaches rapidly normal levels. TNF alpha, IL-6 and sIL-2R reach maximal levels 24-48 hours after the onset of surgery with a subsequent slow decline. All acute phase proteins (APP) have prolonged dynamics with an elevation within +72 hours. A significant correlation was proved between the leptin concentration and TNF alpha 24 hours after surgery (r = 0.43, p < 0.05) and between leptin and IL-6 24 hours after surgery (r = 0.32, p < 0.05).

The dynamics of the plasma leptin concentration during the postoperative period differ from the typical development of early indicators of the systemic inflammatory response--cytokines as well as from the dynamics of APP. Leptin elevation during this period may contribute to anorexia of patients after major surgery. However, rapid normalization of the level within 48 hours after surgery indicates however that leptin is involved also in other, so far unspecified factors with an anorectic action.