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51.
Genetic and environmental influences on behavioral and neurochemical aspects of emotionality in rats
Summary Three pairings of rats (two derived from divergent, selective breeding and one from divergent environmental conditions) were compared with regard to behavioral and hormonal parameters. Striking differences were observed: results obtained in our own laboratory as well as those found in a review of the literature pointed to higher emotionality (e.g., increased defecation and corticosterone secretion, etc.) in Roman low-avoidance, Wistar-Kyoto and group-housed rats, as compared to their respective counterparts, Roman high-avoidance, spontaneously hypertensive, and individually housed Wistar rats. Concomitant receptor binding studies reviewed here (3H-diazepam- and3H-imipramine-binding sites) have revelaed, however, less consistent intrapair differences. 相似文献
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The venoms of predatory cone snails harbor a rich repertoire of peptide toxins that are valuable research tools, but recently
have also proven to be useful drugs. Among the conotoxins with several disulfide bridges, the O-superfamily toxins are characterized
by a conserved cysteine knot pattern: C-C-CC-C-C. While ω-conotoxins and κ-conotoxins block Ca2+ and K+ channels, respectively, the closely related δ- and μO-conotoxins affect voltage-gated Na+ channels (Nav channels). δ-conotoxins mainly remove the fast inactivation of Nav channels and, thus, functionally resemble long-chain scorpion α-toxins. μO-conotoxins are functionally similar to μ-conotoxins,
since they inhibit the ion flow through Nav channels. Recent results from functional and structural assays have gained insight into the underlying molecular mechanisms.
Both types of toxins are voltage-sensor toxins interfering with the voltage-sensor elements of Nav channels.
Received 27 December 2006; received after revision 30 January 2007; accepted 19 February 2007 相似文献
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Bitter peptides and bitter taste receptors 总被引:1,自引:0,他引:1
Bitter peptides are a structurally diverse group of oligopeptides often generated in fermented, aged, and hydrolyzed food
products that make them unfavorable for consumption. Humans perceive bitterness by a repertoire of 25 human bitter receptors,
termed T2Rs. Knowledge of the structural features of bitter receptors and of the factors that stimulate bitter receptors will
aid in understanding the mechanism responsible for bitter taste perception. This article reviews the current knowledge regarding
structural features of bitter peptides and bitter taste receptors.
Received 24 November 2008; received after revision 11 December 2008; accepted 16 December 2008 相似文献
58.
J. Kim D. C. Han J. M. Kim S. Y. Lee S. J. Kim J. R. Woo J. W. Lee S.-K. Jung K. S. Yoon H. G. Cheon S. S. Kim S. H. Hong B.-M. Kwon 《Cellular and molecular life sciences : CMLS》2009,66(10):1766-1781
Indenone KR-62776 acts as an agonist of PPARγ without inducing obesity in animal models and cells. X-ray crystallography reveals
that the indenone occupies the binding pocket in a different manner than rosiglitazone. 2-Dimensional gel-electrophoresis
showed that the expression of 42 proteins was altered more than 2.0-fold between KR-62776- or rosiglitazone-treated adipocyte
cells and control cells. Rosiglitazone down-regulated the expression of ERK1/2 and suppressed the phosphorylation of ERK1/2
in these cells. However, the expression of ERK1/2 was up-regulated in KR-62776-treated cells. Phosphorylated ERK1/2, activated
by indenone, affects the localization of PPARγ, suggesting a mechanism for indenone-inhibition of adipogenesis in 3T3-L1 preadipocyte
cells. The preadipocyte cells are treated with ERK1/2 inhibitor PD98059, a large amount of the cells are converted to adipocyte
cells. These results support the conclusion that the localization of PPARγ is one of the key factors explaining the biological
responses of the ligands.
Received 04 March 2009; received after revision 13 March 2009; accepted 17 March 2009 相似文献
59.
药物分子对接所涉及的搜索空间非常巨大,需要耗费大量的时间,并且对计算环境也有较高的要求.将网格技术应用于药物分子对接中,能有效解决上述问题.通过应用改进的遗传算法多种群竞争机制的对接演化模型GADock,以信息熵控制设计空间的收缩,增强了进化的有效性,显著地提高了对接效率、利用网格数据传输和网格任务调度等网格技术对分子对接过程进行了优化,有效利用了网格节点资源,并降低了药物分子的对接时间.实例测试表明了药物分子对接与网格技术相结合的合理性及有效性. 相似文献
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