The investigation of changes in ghrelin, obestatin and heat shock protein?70 in coronary artery bypass greft (CABG) surgery with cardio-pulmonary bypass (CPB)

Cardiopulmonary bypass (CBP) is non-physiological event maintaining the circulation outside the body. This process is a unique stress factor for organism, all organs are affected from the changes and developing systemic inflammatory response in their circulations. Also the anesthesia applied during CBP, surgical stress, hypothermia, and hemodilution give contribution to the metabolic changes. The secretions of endocrine organs such as adrenal glands, throid, pancreas, and pituitary change during CBP.In this study, we aimed to investigate changes of ?ghrelin? newly discovered, and known as releasing growth hormone, ?obestatin? which acts against ghrelin and ?heat shock protein 70 (HSP-70)? which is the most induced heat shock protein during stress situations in patients underwent coronary artery bypass greft with cardio-pulmonary bypass. In addition, these changes related with each other are among the objectives of the study.In our study, levels of serum ghrelin, obestatin and HSP 70 assessed at total 7 stages in volunteers underwent CABG with CBP. These biochemical evaluations were made and statistically studied at these stages as T1: pre-anesthesia induction, T2: pre CBP, T3: 5 minutes before cross clamp was removed, T4: 5 minutes after cross clamp was removed, T6: postoperative 24th hours, T7: postoperative 48th hour.Total 25 volunteer patients were included in the study. All patients underwent CABG with CBP. Whole venous blood samples were taken from central venous catheter.As a result, it was showed that a gradual decrease in serum ghrelin levels related to biochemical data measured at stated times in patients underwent CABG with CBP. When the patient?s temperature was 30 degrees, the lowest values were detected. After that, the first values were reached with increment. They were reached over basal values at postoperative 24th and 48th hours. When women compared with men, women?s acyl ghrelin levels were detected significantly high at postoperative 48th hour (p<0,05). Serum ghrelin levels were gradually decreased and when patients?s temperature were 30 degree, these levels reached the lowest levels. After that temperature, these levels increased again and reached near the preoperative level at postoperative 48th hour. When women compared with men, there was no difference between them. Serum HSP 70 levels were detected increased before CBP. Peak values were detected at 5 minutes after removing cross clamp. A gradual decrease was detected untill 48th hour. Serum HSP 70 levels were detected significantly higher at 5 minutes before removing cross clamp in women when compared with men (p<0,05).We think that the cause of these changes is the changes in body temperature and developing antienflamatuar response related to CBP.Keywords: Cardiopulmonary bypass, coronary artery bypass greft surgery, ghrelin, obestatin, heat shock protein-70