Objective-Asymmetric dimethylarginine (ADMA) is widely believed to be an endogenous nitric oxide synthase (eNOS) inhibitor. However, in this study, we examined our hypothesis that the long-term vascular effects of ADMA are not mediated by inhibition of endothelial NO synthesis. Methods and Results-ADMA was infused in wild-type and eNOS-knockout (KO) mice by osmotic minipump for 4 weeks. In wild-type mice, long-term treatment with ADMA caused significant coronary microvascular lesions. Importantly, in eNOS-KO mice, treatment with ADMA also caused an extent of coronary microvascular lesions that was comparable to that in wild-type mice. These vascular effects of ADMA were not prevented by supplementation of L-arginine, and vascular NO production was not reduced by ADMA treatment. Treatment with ADMA caused upregulation of angiotensin-converting enzyme (ACE) and an increase in superoxide production that were comparable in both strains and that were abolished by simultaneous treatment with temocapril (ACE inhibitor) or olmesartan (AT 1 receptor antagonist), which simultaneously suppressed vascular lesion formation. Key Words: asymmetric dimethylarginine Ⅲ arteriosclerosis Ⅲ nitric oxide Ⅲ endothelial nitric oxide synthase Ⅲ mice E ndothelium-derived nitric oxide (NO), synthesized from L-arginine by endothelial NO synthase (eNOS), has several important antiatherogenic actions. 1-5 Indeed, reduction of endothelial NO synthesis (endothelial dysfunction) predisposes the blood vessel to arteriosclerosis, 1-5 and the eNOS-deficient (eNOS-KO) mice exhibit accelerated vascular lesion formation. 6,7 As pharmacological tools to inhibit endothelial NO synthesis, synthetic L-arginine analogues have been used in vitro and in vivo. Among them, N -nitro-L-arginine methyl ester (L-NAME) is the most frequently used agent. [1][2][3][4][5] Long-term treatment with L-NAME is known to cause arteriosclerotic coronary lesions, especially at microvascular levels, in experimental animals. 8,9 This model with L-NAME is regarded as a useful animal model for examining the protective roles of endothelium-derived NO in the pathogenesis of arteriosclerosis. 8,9 See cover However, it is controversial whether these vascular effects of L-NAME are caused primarily by the inhibition of endothelial NO synthesis for the following reasons: first, the importance of endothelium-derived NO decreases as the vessel size becomes smaller, 10 whereas L-NAME-induced vascular lesions are prominent at microvascular levels; 8 second, long-term treatment with L-NAME does not reduce eNOS activity; 11 third, multiple actions of L-NAME other than simple inhibition of NO synthesis have been reported. 12,13 The most appropriate way to address this issue is to use mice that are deficient in the eNOS gene and to examine whether long-term treatment with L-NAME causes coronary vascular lesions in those mice. We have recently shown that treatment with L-NAME causes a comparable extent of Conclusions-These

Green nanocomposites based on renewable plant oils have been developed. Curing of epoxidized plant oils in the presence of organophilic montmorillonite produced triglyceride−clay nanocomposites showing flexible property. A nanocomposite with homogeneous structure was obtained, in which silicate layers of the clay were intercalated and randomly distributed in the polymer matrix.

Structural analysis of the BRM2 gene involved in melanin biosynthesis of the Japanese pear pathotype of Alternaria alternata suggested that this gene encodes 1,3,8-trihydroxynaphthalene reductase. Targeted disruption of the BRM2 gene did not affect pathogenicity, vegetative growth, or the number of conidia produced. Targeted disruption, however, did reduce conidial size and septal number, suggesting that melanin is associated with conidial development. The conidia of brm2 mutant transformants were more sensitive to UV light than those of the wild type, demonstrating that melanin confers UV tolerance.

Mesoporous polyacrylonitrile (PAN) monolith has been fabricated by a template-free approach using the unique affinity of PAN towards a water/dimethyl sulfoxide (DMSO) mixture. A newly developed Thermally Induced Phase Separation Technique (TIPS) has been used to obtain the polymer monoliths and their microstructures have been controlled by optimizing the concentration and cooling temperature.