[Comparison of insulin secretion and resistance in patients with acute coronary syndrome]

Bulk of increasing evidences indicates that the postprandial hyperglycemia is considered as a risk factor for atherosclerosis and coronary artery disease. Several different pathophysiologic mechanisms contribute to disturbances in glucose homeostasis. To evaluate the frequency of post-challenge hyperglycemia in acute coronary syndrome [ACS] patients with previously undiagnosed diabetes and fasting glucose concentrations of less than 126 mg/dl in Qazvin and also to determine the main cause of glucose intolerance. This analytic study was accomplished at Qazvin Metabolic Diseases Research Center in 2007. A total of 120 patients with acute coronary syndrome who met the recommended inclusion criteria were studied. An oral glucose tolerance test with sampling at minutes 0, 30 and 120 was performed for each patient. The data were statistically investigated by analysis of variance, Pearson correlation and chi-square test. Normal glucose tolerance [NGT], impaired glucose tolerance [IGT], and diabetes mellitus [DM] were found in 40, 48, and 32 cases of patients, respectively. The homeostasis model assessment for insulin resistance [HOMA-IR] showed no substantial difference among three groups however, the insulinogenic index in IGT and DM patients was lower than those of NGT group with two-hour plasma insulin level higher in the former groups compared to the latter. Post-challenge hyperglycemia, caused primarily by impaired insulin initial secretion and muscle insulin resistance, is common among the ACS patients with previously undiagnosed diabetes in Qazvin. Hyperinsulinemia is a good indicator of insulin resistance in postprandial hyperglycemia. Assessing the oral glucose tolerance test of post-challenge hyperglycemia is essential in ACS patients with previously undiagnosed diabetes

[Study of angiotensin converting enzyme [ACE] inhibitory effects of main Papaver spp. alkaloids]

Angiotensin converting enzyme [ACE] converts the inactive angiotensin I to [a potent vasoconstrictor and aldosterone releaser] angiotensin II. Inhibitors of ACE are valuable drugs in the treatment of hypertension, and heart failure. These inhibitors have a natural origin and non-peptide drugs were synthesized from the natural lead compounds. However, because of some side effects such as dry cough, many investigators are searching in natural products to find better and more selective lead compounds. There are reports on the interaction between rennin-angiotensin system and endogenous opioid system. Morphine and endogenous opioids have reported to inhibit ACE. In this research we examined the possible inhibitory effects of purified papaver's main alkaloids on the activity of purified rabbit lung ACE. We found that only papaverin at 1 mM inhibited the enzyme by 40%. The Km value of ACE increased while Vmax decreased in papaverin treated samples. We conclude that part of hypotensive effects of papaverin may be related to ACE inhibition, and this compound will be a suitable lead compound for further investigation