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Adopting self-determination theory and the perceived characteristics of innovation as the theoretical background, this study investigates the school teachers' willingness to adopt and reuse an e-learning system. Three hundred and eighty-eight valid questionnaires were collected for analysis using structural equation modelling. The results demonstrated that perceived autonomy and competence have positive influences on intrinsic motivation, while subjective norm and organisational policy have positive influences on extrinsic motivation in both the reuse and the adoption models. Further, an improvement with regard to perceived characteristics of innovation in the e-learning system can facilitate teachers' intrinsic motivation to continue to use the system usage. Both intrinsic and extrinsic motivations affected the willingness to reuse or adopt the e-learning system differently. Finally, the theoretical and practical implications of this work are also discussed.

Purpose: In this paper, Yale model was adopted to understand how the characteristics of a green message (goal framing, argument volume and argument consistency), its source (source credibility) and its receivers (environmental consciousness) influence the communication process regarding the receivers' perceptions and attitudes (information value, persuasiveness and communication effectiveness) and their intention to spread the green message. Design/methodology/approach: Eight scenarios of factorial design were developed to test the effects of a message on receivers' perceptions and attitudes. 1,157 valid questionnaires were used to conduct AMOS-SEM and ANOVA analyses. Findings: The analytical results showed significant differences between the persuasive effects of Scenarios 1 and 8. A high level of environmental consciousness significantly affected the relationships between the message characteristics, source credibility and information value, leading to a higher intention to share the green messages. Research limitations/implications: The Yale model was applied to online persuasion to examine the receivers' perceptions of and attitudes toward a green message and their intention to share it on social networking sites (SNSs). Being environmentally conscious can strengthen the perception that the receivers of an online green message have of the source credibility and information value. The Yale model proved to represent the online green message-sharing context and explain how to persuade online users more effectively. Practical implications: This study suggests that green message providers should present content emphasizing the losses associated with inaction, thus increasing the receivers' acceptance of the message's persuasiveness. Additionally, with the assistance of supportive measures, such as national education programs, government policies and actions showing corporate social responsibility, the environmental awareness of individuals can encourage them to share green message posts on SNSs and engage in green practices. Social implications: A significant effect of the message characteristics (goal framing × argument volume × argument consistency) was observed on SNS users' perceived source credibility and information value. Therefore, key opinion leaders, governments, and organizations who want to promote green ideas and attract public attention are encouraged to provide messages emphasizing the costs of inaction and contain arguments with a sufficient number of responses strongly supporting the original message. This could arouse the concern for green issues among online communities. Originality/value: A Yale model research framework was developed to investigate the effect of message characteristics on the intention to share green messages online. Receivers' environmental consciousness played a vital role in this message-sharing process. [ABSTRACT FROM AUTHOR]

The early stage of diabetic nephropathy (DN) is linked to proteinuria. Transforming growth factor (TGF)-[beta]1 increases glomerular permeability to albumin ([P.sub.alb]), whereas 20-HETE and EETs reduce [P.sub.alb]. To investigate the impact of hyperglycemia and hyperlipidemia on 20-HETE, EETs, and TGF-[beta]1 in the glomeruli, rats were divided into four groups: ND rats were fed a normal diet, HF rats were fed a high-fat diet, STZ rats were treated with 35 mg/kg of streptozotocin, and HF/STZ rats were fed a HF diet and treated with STZ. After 10 wk on these regimens, blood glucose, urinary albumin, serum cholesterol, serum triglyceride levels, and the kidney-to-body weight ratio were significantly elevated in STZ and HF/STZ rats compared with HF and ND rats. STZ and HF/STZ rats had histopathologic changes and abnormal renal hemodynamics. Expression of glomerular CYP4A, enzymes for 20-HETE production, was significantly decreased in STZ rats, whereas expression of glomerular CYP2C and CYP2J, enzymes for EETs production, was significantly decreased in both STZ and HF/STZ rats. Moreover, glomerular TGF-[beta]1 levels were significantly greater in STZ and HF/STZ rats than in HF and ND rats. Five-week treatment of STZ rats with clofibrate induced glomerular CYP4A expression and 20-HETE production, but reduced glomerular TGF-[beta]1 and urinary protein excretion. These results demonstrate that hyperglycemia increases TGF-[beta]1 but decreases 20-HETE and EETs production in the glomeruli, changes that may be important in causing glomerular damage in the early stage of DN. CYP-derived eicosanoids; streptozotocin; kidney

We previously reported that inhibition of nitric oxide (NO) synthesis by N-nitro-L-arginine methyl ester (L-NAME) during late pregnancy leads to increased production of renal vascular 20-hydroxyeicosatetraenoic acid (20-HETE), a cytochrome P-450 (CYP) 4A-derived vasoconstrictor, in pregnant rats. However, the effect of upregulation of vascular 20-HETE production on renal function after NO inhibition is not known. To test the hypothesis that increased gestational vascular 20-HETE synthesis after NO inhibition is involved in mediating blood pressure and renal functional changes, we first determined the I[C.sub.50] value of the effect of nitroprusside (SNP), a NO donor, on renal 20-HETE production in cortical microsomes. We then divided pregnant rats and age-matched virgin rats into a vehicle control group, an L-NAME treatment group (0.25 mg/ml in drinking water), and a group treated with L-NAME plus N-methylsulfonyl- 12,12-dibromododec-11-enamide (DDMS; CYP4A-selective inhibitor, l0 mg x [kg.sup.-1] x [day.sup.-1] iv). After 4 days of treatment, we measured blood pressure, renal blood flow (RBF), renal vascular resistance (RVR), and glomerular filtration rate (GFR) in each group. The addition of SNP (I[C.sub.50] = 22 [micro]M) decreased renal cortical 20-HETE production. In pregnant rats, L-NAME treatment led to significantly higher mean arterial pressure (MAP) and RVR, and lower RBF and GFR. Combined treatment with DDMS and L-NAME significantly attenuated the increases in MAP and RVR and the decrease in GFR, but not the reduction in RBF induced by L-NAME treatment. L-NAME and L-NAME plus DDMS had no significant impact on renal hemodynamics in virgin rats. In addition, chronic treatment with DDMS selectively inhibited cortical 20-HETE production without a significant effect on CYP4A expression in L-NAME-treated pregnant rats. In conclusion, NO effectively inhibits renal cortical microsomal 20-HETE production in female rats. In pregnant rats, the augmentation of renal 20-HETE production after NO inhibition is associated with increased MAP and RVR, whereas decreased GFR is negated by treatment of a selective and competitive CYP4A inhibitor. These results demonstrate that the interaction between renal 20-HETE and NO is important in the regulation of renal function and blood pressure in pregnant rats. pregnancy; cytochrome P-450; arachidonic acid; eicosanoid; kidney; nitric oxide; hypertension

Epoxyeicosatrienoic acids (EETs), which belong to cytochrome P-450 (CYP)-derived eicosanoids, have been implicated to vasodilate renal arterioles, inhibit sodium transport in the nephron, and regulate blood pressure in several animal models. Because pregnancy is associated with changes of blood pressure, the aim of this study was to examine whether renal EET synthesis is altered and whether EETs are involved in blood pressure regulation during pregnancy in rats. Renal microsomal epoxygenase activity increased by 47, 97, and 63% on days 6, 12, and 19 of gestation, respectively. The elevation of epoxygenase activity during pregnancy was associated with an increase in CYP2C11, CYP2C23, and CYP2J2 protein expression on days 6, 12, and 19 of gestation. Moreover, immunohistochemical analysis showed that renal tubular CYP2C11, CYP2C23, and CYP2J2 expression was significantly increased in pregnant rats on days 6, 12, and 19 of gestation. Administration of 6-(2-propargyloxyphenyl)hexanoic acid (PPOH), a selective epoxygenase inhibitor, caused a dose-dependent inhibition of microsomal expoxygenase activity without a significant effect on [omega]-hydroxylase activity in female rats. Interestingly, administration of PPOH (20 mg x [kg.sup.-1] x [day.sup.-1] for 4 days starting on day 15 of pregnancy) increased blood pressure by 21 mmHg and caused a significant decrease in the body weight of fetal pups (1.3 [+ or -] 0.08 g in control vs. 1.1 [+ or -] 0.06 g in PPOH). Moreover, PPOH treatment significantly decreased renal microsomal epoxygenase activity and the expression of CYP2C11, CYP2C23, and CYP2J in pregnant rats. This study demonstrates that EET synthesis in the kidney is elevated during pregnancy, and CYP2C11, 2C23, and CYP2J2 are responsible for the change of renal EET synthesis. The inhibition results demonstrate that the downregulation of renal epoxygenase activity by PPOH causes hypertension in pregnant rats. This study suggests that EETs may contribute to the control of blood pressure during pregnancy. blood pressure; cytochrome P-450; epoxyeicosatrienoic acids

20-Hydroxyeicosatetraenoic acid (20-HETE), which promotes renal vasoconstriction, is formed in the rat kidney primarily by cytochrome P-450 (CYP) 4A isoforms (4A1, 4A2, 4A3, 4A8). Nitric oxide (NO) has been shown to bind to the heme moiety of the CYP4A2 protein and to inhibit 20-HETE synthesis in renal arterioles of male rats. However, it is not known whether NO interacts with and affects the activity of CYP4A1 and CYP4A3, the major renal CYP4A isoforms in female rats. Incubation of recombinant CYP4A1 and 4A3 proteins with sodium nitroprusside (SNP) shifted the absorbance at 440 nm, indicating the formation of a ferric-nitrosyl-CYP4A complex. The absorbance for CYP4A3 was about twofold higher than that of CYP4A1. Incubation of SNP or peroxynitrite (PN; 0.01-1 mM) with CYP4A recombinant membranes caused a concentration-dependent inhibition of 20-HETE synthesis, with both chemicals having a greater inhibitory effect on CYP4A3-catalyzed activity. Moreover, incubation of CYP4A1 and 4A3 proteins with PN (1 mM) resulted in nitration of tyrosine residues in both proteins. In addition, PN and SNP inhibited 20-HETE synthesis in renal microvessels from female rats by 65 and 59%, respectively. We previously showed that microvessel CYP4A1/CYP4A3 expression and 20-HETE synthesis are decreased in late pregnancy. Therefore, we investigated whether such a decrease is dependent on NO, the synthesis of which has been shown to increase in late pregnancy. Administration of [N.sup.G]-nitro-L-arginine methyl ester (L-NAME) to pregnant rats for 6 days (days 15-20 of pregnancy) caused a significant increase in systolic blood pressure, which was prevented by concurrent treatment with the CYP4A inhibitor 1-aminobenzotriazole (ABT). Urinary N[O.sub.2]/N[O.sub.3] excretion decreased by 40 and 52% in L-NAME-and L-NAME + ABT-treated groups, respectively. Interestingly, renal microvessel 20-HETE synthesis showed a marked increase following L-NAME treatment, and this increase was diminished with coadministration of ABT. These results demonstrate that NO interacts with CYP4A proteins in a distinct manner and it interferes with renal microvessel 20-HETE synthesis, which may play an important role in the regulation of blood pressure and renal function during pregnancy. cytochrome P-450 4A; [N.sup.G]-nitro-L-arginine methyl ester