Association between angiotensin-converting enzyme gene polymorphism and coronary artery disease

An insertion/deletion (I/D) polymorphism in the gene for angiotensin-converting enzyme (ACE) is associated with myocardial infarction and other cardiac pathology. There is evidence for a role of the renin-angiotensin system in cell growth and in the repair of damaged arterial walls, so the ACE gene is postulated to be a candidate gene affecting the important clinical problem of coronary artery disease (CAD), In view of the clinical importance of the ACE as a major marker of cardiovascular diseases, we investigated the I/D polymorphism of the ACE gene in Turkish CAD patients in comparison with control subjects to evaluate a possible association between CAD and the gene encoding ACE. Polymerase chain reaction, restriction fragment length polymorphism, and agarose gel electrophoresis techniques were used to determine the ACE genotype in 58 subjects. The frequencies of ACE D and ACE I allele among the patients with CAD were 62.26% and 37.73 % and in the control subjects were 49.3 % and 50.76 %, respectively. The greater frequency of deletion allele (D) was in the CAD group than in the control subjects was significant (P < 0.01)

The effect of captopril on membrane bound enzymes in ischemia-reperfusion injury

There is substantial evidence that Na+K+/Mg2+ ATPase and Ca2+/Mg2+ ATPase enzymes would effect the membrane integrity. Forty guinea pig (n = 10 in each group) hearts were studied in an isolated Krebs-Henseleit solution perfused Langendorff cardiac model. The first group was utilized as the control group. Group 2 hearts were arrested with captopril (200 mu mol/l) added St Thomas Hospital Cardioplegic Solution (STHCS). Group 3 animals were pretreated with oral captopril (0.3 mg/kg/twice a day) for 10 days and then arrested with STHCS. Group 4 hearts were again pretreated with oral captopril (0.3 mg/kg/twice a day for 10 days) arrested with STHCS and reperfused with captopril added Krebs-Henseleit solution (200 mu mol/l). Hearts were subjected to normothermic global ischemia for 90 min and than were reperfused at 37 degrees C. When the treated groups were compared with control, best results were achived by group 4. The Na+K+ and Ca2+/Mg2+ ATPase levels increased from 466.38 +/- 5.99 to 564.13 +/- 7.77 and 884.69 +/- 9.13 to 1254.29 +/- 5.75 nmol Pi/mg/prot/h respectively (P < 0.05). These results suggest that captopril protects the membrane integrity and thus played a role at the recovery of depressed membrane bound Na+K+/Mg2+ ATPase and Ca-2 (+)/Mg2+ ATPase activity and also in ischemia-reperfusion injury. (C) 2000 The International Society for Cardiovascular Surgery. Published by Elsevier Science Ltd. All rights reserved

Trace element alterations before and after cardiopulmonary bypass in patients undergoing coronary artery bypass grafting

Trace elements (TE) are known to play a key role in myocardial metabolism. In this study, the serum levels of zinc (Zn) and copper (Cu) were determined in 15 consecutive patients with coronary artery disease admitted for coronary artery bypass grafting. To analyze the trace elements, blood samples were drawn into metal-free tubes just prior to the start of cardiopulmonary bypass; within the first 30 min of cardiopulmonary bypass; 30 min following cardiopulmonary bypass; first postoperative day; 2nd postoperative day and 3rd postoperative day. Trace element analyses were performed using atomic absorption spectrophotometry. Mean age was 53.1 +/- 8.7 years and 87% were men. Mean cardiopulmonary bypass time was 80.8 +/- 18.1 min. The preoperative serum concentrations of zinc were normal. There were remarkable decreases in serum levels of Cu and Zn on the second postoperative day in all patients compared to the preoperative levels of Cu and Zn. On the first postoperative day, mean levels of zinc were decreased and a gradual rise followed on the third day. All patients had serum zinc above the lower limit of normal range. These data indicate that severe loss of various trace elements might occur in patients undergoing cardio pulmonary bypass