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We examined whether an additive treatment with an angiotensin receptor blocker, olmesartan, reduces the mortality and morbidity in hypertensive patients with chronic heart failure (CHF) treated with angiotensin-converting enzyme (ACE) inhibitors, β-blockers, or both. In this prospective, randomized, open-label, blinded endpoint study, a total of 1147 hypertensive patients with symptomatic CHF (mean age 66 years, 75% male) were randomized to the addition of olmesartan (n = 578) to baseline therapy vs. control (n = 569). The primary endpoint was a composite of all-cause death, non-fatal acute myocardial infarction, non-fatal stroke, and hospitalization for worsening heart failure. During a median follow-up of 4.4 years, the primary endpoint occurred in 192 patients (33.2%) in the olmesartan group and in 166 patients (29.2%) in the control group [hazard ratio (HR) 1.18; 95% confidence interval (CI), 0.96–1.46, P = 0.112], while renal dysfunction developed more frequently in the olmesartan group (16.8 vs. 10.7%, HR 1.64; 95% CI 1.19–2.26, P = 0.003). Subgroup analysis revealed that addition of olmesartan to combination of ACE inhibitors and β-blockers was associated with increased incidence of the primary endpoint (38.1 vs. 28.2%, HR 1.47; 95% CI 1.11–1.95, P = 0.006), all-cause death (19.4 vs. 13.5%, HR 1.50; 95% CI 1.01–2.23, P = 0.046), and renal dysfunction (21.1 vs. 12.5%, HR 1.85; 95% CI 1.24–2.76, P = 0.003). Additive use of olmesartan did not improve clinical outcomes but worsened renal function in hypertensive CHF patients treated with evidence-based medications. Particularly, the triple combination therapy with olmesartan, ACE inhibitors and β-blockers was associated with increased adverse cardiac events. This study is registered at clinicaltrials.gov-NCT00417222.

NADPH-cytochrome c reductase [NADPH: ferricytochrome oxidoreductase, EC 1.6.2.4] was highly purified from the membrane fraction of porcine polymorphonuclear leukocytes by column chromatographies on DEAE cellulose DE-52, 2',5'-ADP-agarose, Sephacryl S-300, and Bio-gel HTP. Upon sodium dodecyl sulfate polyacrylamide gel electrophoresis, the purified preparation gave a main band with a molecular weight of 80,000. The enzyme contained 0.79 mol of FAD and 0.88 mol of FMN per mol, and was capable of exhibiting a benzphetamine N-demethylation activity in the presence of cytochrome P-450 purified from rabbit liver microsomes and dilauroylphosphatidylcholine, as is the case with liver NADPH-cytochrome P-450 reductase. The cytochrome c reductase activity of the polymorphonuclear leukocytes (PMN) enzyme was precipitated with rabbit anti-guinea pig liver NADPH-cytochrome P-450 reductase IgG followed by addition of guinea pig anti-rabbit IgG antibody. The biochemical and immunological properties of the PMN enzyme so far examined were similar to those of the liver enzyme, although its function in leukocytes has not yet been determined.

Pyridine nucleotide-oxidizing enzymes in guinea pig polymorphonuclear leukocytes were separated by Sephacryl S-300 gel filtration of the sonicated cells in the presence of 0.2% Triton X-100. Two peaks of NADPH-dependent cytochrome c reductase activities with apparent molecular weights of 400,000 and 120,000 were detected. The replacement of NADPH by NADH, on the other hand, revealed two NADH-dependent cytochrome c reductases with apparent molecular weights of 300,000 and 120,000. The addition of 40 microM menadione to assay mixtures considerably enhanced all the cytochrome c-reducing activities, and the enhancement was accompanied by the formation of superoxide anion (O2-). Analysis of the subcellular localizations of these enzymes by fractional centrifugation demonstrated that the NADPH-dependent enzyme (400,000 daltons) was membrane-bound in nature, and that the NADH-dependent enzyme (300,000 daltons) and the NADPH- and NADH-dependent enzyme (120,000 daltons) existed in the cytosol of leukocytes. Thus, the leukocytes contained at least three types of menadione-dependent, O2--forming enzymes: a membrane-bound NADPH-oxidizing enzyme, and soluble NADH-oxidizing and NAD(P)H-oxidizing enzymes.

The membrane fraction of guinea pig polymorphonuclear leukocytes stimulated with phorbol myristate acetate exhibits the respiratory burst NADPH oxidase activity. This activity is markedly unstable at 37 degrees C, disappearing with a half-life of 11.0 min. When the membrane fraction was pretreated with 0.1% glutaraldehyde, the NADPH oxidase was found to become more stable; its half-life increased about sixfold without any enhancement of the initial activity. The glutaraldehyde treatment of the membrane fraction also protected the NADPH oxidase against inactivation with 0.1-0.2% Triton X-100. These stabilizing effects of glutaraldehyde on the NADPH oxidase seem to be due to its protein cross-linking ability, since its monovalent analogue, butyraldehyde, did not show any effect on the NADPH oxidase activity. In fact, sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that glutaraldehyde cross-linked many proteins constituting the membrane.