Effects of omapatrilat on blood pressure and insulin sensitivity in an animal model of insulin resistance.

OBJECTIVE: To assess the effects of omapatrilat, fosinopril and placebo on blood pressure, plasma insulin, glucose and triglycerides concentrations in Zucker rats, a model for insulin resistance. DESIGN: Double blind, parallel, prospective trial. METHODS: Forty-two male obese Zucker (falfa) rats (aged 13-18 week) initially weighing 400-600 g were used for the experiments. Omapatrilat (n = 14), placebo (n = 14) or fosinopril (n = 14) were administrated once daily at 10 micromol/kg oral for 15 days. At baseline and at the end of the study, a tail-cuff blood pressure measurement was performed; an oral glucose tolerance test was done at the end of the study. RESULTS: Omapatrilat and fosinopril resulted in significant lower systolic blood pressure compared to the placebo group (p < 0.001). This parameter was significantly lower in the omapatrilat group compared with fosinopril-treated rats (116+/-9 vs 125+/-4 mmHg, p < 0.05). After an overnight fast, there was no difference in the fasting glucose concentrations among treatment groups. The basal and post-glucose challenge insulin concentrations were lower in the omapatrilat group compared to the placebo group. No difference was observed in the fasting triglycerides concentrations between the treatment groups. CONCLUSIONS: Compared to placebo and fosinopril treatment, omapatrilat results in lower arterial blood pressure in an animal model of insulin resistance. The results suggest that omapatrilat may have a positive effect on insulin sensitivity.

Lack of agreement between the World Health Organization Category of impaired glucose tolerance and the American Diabetes Association category of impaired fasting glucose.

OBJECTIVE: To study the concordance between the 1997 American Diabetes Association (ADA) impaired fasting glucose (IFG) category with the World Health Organization (WHO) impaired glucose tolerance (IGT) status in a population with a high prevalence of diabetes. RESEARCH DESIGN AND METHODS: We analyzed the oral glucose tolerance tests (OGTTs) carried out at the Instituto Nacional de la Nutrición Salvador Zubiran (INNSZ) central laboratory from June to December 1997. We included patients with fasting plasma glucose (FPG) between 60 and 160 mg/dl. The results from the glucose tolerance test were selected as the gold standard. RESULTS: Among the 1,802 glucose tolerance test results available for analysis, 1,706 fulfilled the requirements to be included. Diabetes and IGT were remarkably more frequently diagnosed when the WHO criteria were applied. The new ADA criteria failed to diagnose 69% of WHO diabetic patients and the vast majority of WHO glucose-intolerant subjects. Using the new criteria, 82% were considered normal. Of the IFG subjects, 39% were classified as diabetic and 23% were normal according to the 2-h postchallenge glucose values. Only 37% of the IFG patients were, in fact, glucose intolerant according to the WHO criteria. CONCLUSIONS: Our results clearly show that the 1997 ADA criteria are less sensitive for diagnosing diabetes than OGTT-based WHO criteria. Even more important, there is poor agreement between the WHO category of IGT and the ADA category of IFG.