Judged attractiveness in relation to respondent's sex, age, and perceived disability of targets

The purpose of this study was to investigate the effects of a target's age, sex and perceived disability and a respondent's sex on judgements of attractiveness. The procedure involved the video-tape presentation of four physically handicapped individuals (targets) to a sample of 240 non-handicapped individuals (respondents). The target persons, two male and two females who normally wear lower extremity orthotic equipment, were subclassified into groups of young and old and each was viewed by an independent group of 20 respondents (one-half males) in the following three conditions: I - without a brace, II - with a conventional style brace, and III - with a cosmetic-functional brace. It was hypothesized that all targets, regardless of the condition in which they appeared, would be judged as physically handicapped, but that differences in judged attractiveness would be found and these differences would be related to the sex of a respondent and the age and sex of the target. It was expected that female respondents would give more favorable ratings than male respondents, regardless of the degree of target disability, and that female targets would receive more favorable ratings than would male targets. Also, younger targets were expected to be judged more attractive than older targets. With reference to the three target conditions, it was predicted that targets in Condition III (cosmetic-functional brace) would receive more favorable ratings than when they appeared in Condition I (without a brace) and Condition II (wearing the conventional style brace)...Psychology, Department o

Mitochondrial arginase II modulates nitric-oxide synthesis through nonfreely exchangeable L-arginine pools in human endothelial cells

Reduced synthesis of nitric oxide ( NO) contributes to the endothelial dysfunction and may be related to limited availability of L-arginine, the common substrate of constitutive nitric-oxide synthase ( NOS) and cytosolic arginase I and mitochondrial arginase II. To determine whether arginases modulate the endothelial NO synthesis, we investigated the effects of the competitive arginase inhibitor N omega-hydroxy-nor-L-arginine (NorNOHA) on the activity of NOS, arginases, and L-arginine transporter and on NO release at surface of human umbilical vein endothelial cells (HUVECs). In unstimulated cells, Nor-NOHA dose-dependently reduced the arginase activity with maximal inhibition at 20 mu M. When HUVECs were stimulated by thrombin without extracellular L-arginine, Nor-NOHA dose-dependently increased the NOS activity and the NO release with maximal effects at 20 mu M. Extracellular L-arginine also dose-dependently increased NO release and arginase activity. When HUVECs were stimulated by thrombin in the presence of 100 mu M L- arginine, NOS activity and NO release were similar in untreated and Nor-NOHA-treated cells. However, despite activation of L- arginine uptake, the inhibition of arginase activity by Nor-NOHA was still significant. The depletion of freely exchangeable L- arginine pools with extracellular L- lysine did not prevent Nor-NOHA from increasing the NO release. This indicates the presence of pools, which are accessible to NOS and arginase, but not exchangeable. Interestingly, the mitochondrial arginase II was constitutively expressed, whereas the cytosolic arginase I was barely detectable in HUVECs. These data suggest that endothelial NO synthesis depends on the activity of arginase II in mitochondria and L-arginine carriers in cell membrane

Endothelial thrombomodulin induces Ca2+ signals and nitric oxide synthesis through epidermal growth factor receptor kinase and calmodulin kinase II

Endothelial membrane-bound thrombomodulin is a high affinity receptor for thrombin to inhibit coagulation. We previously demonstrated that the thrombin-thrombomodulin complex restrains cell proliferation mediated through protease-activated receptor (PAR)-1. We have now tested the hypothesis that thrombomodulin transduces a signal to activate the endothelial nitric-oxide synthase (NOS3) and to modulate G protein-coupled receptor signaling. Cultured human umbilical vein endothelial cells were stimulated with thrombin or a mutant of thrombin that binds to thrombomodulin and has no catalytic activity on PAR-1. Thrombin and its mutant dose dependently activated NO release at cell surface. Pretreatment with anti-thrombomodulin antibody suppressed NO response to the mutant and to low thrombin concentration and reduced by half response to high concentration. Thrombin receptor-activating peptide that only activates PAR-1 and high thrombin concentration induced marked biphasic Ca2+ signals with rapid phosphorylation of PLC beta 3 and NOS3 at both serine 1177 and threonine 495. The mutant thrombin evoked a Ca2+ spark and progressive phosphorylation of Src family kinases at tyrosine 416 and NOS3 only at threonine 495. It activated rapid phosphatidylinositol-3 kinase-dependent NO synthesis and phosphorylation of epidermal growth factor receptor and calmodulin kinase II. Complete epidermal growth factor receptor inhibition only partly reduced the activation of phospholipase C gamma(1) and NOS3. Prestimulation of thrombomodulin did not affect NO release but reduced Ca2+ responses to thrombin and histamine, suggesting cross-talks between thrombomodulin and G protein-coupled receptors. This is the first demonstration of an outside-in signal mediated by the cell surface thrombomodulin receptor to activate NOS3 through tyrosine kinase-dependent pathway. This signaling may contribute to thrombomodulin function in thrombosis, inflammation, and atherosclerosis