Neuroanatomy and neurochemistry of sleep

Sleep is regulated by homeostatic and circadian factors, and the regulation of sleep of mammals shares many molecular properties with the rest state of submammalian species. Several brain structures take part in waking: the basal forebrain, posterior and lateral hypothalamus, and nuclei in the tegmentum and pons. Active sleep mechanisms are located to the preoptic/anterior hypothalamic area. In addition to acetylcholine and monoamines, glutamate and hypocretin/orexin are important waking factors. Gamma-aminobutyric acid and several peptide factors, including cytokines, growth hormone-releasing hormone and prolactin, are related to sleep promotion. Adenosine is an important homeostatic sleep factor acting in basal forebrain and preoptic areas through A1 and A2A receptors. Prolonged waking activates inducible nitric oxide synthase in the basal forebrain, which through energy depletion causes adenosine release and recovery sleep. Numerous genes have been found differentially displayed in waking compared with sleep, and they relate to neural transmission, synaptic plasticity, energy metabolism and stress protection. The genetic background of a few sleep disorders has been solved.     

cAMP的构象及其异构化反应的理论研究

用量子化学密度泛函方法,在B3LYP/6-31G**水平下研究了3’,5’-环核苷单磷酸(cAMP)的构象及构象间的转化反应机理.结果表明:3’,5’-环核苷单磷酸分子具有3种异构体,6种稳定构象,主要键参数的理论计算值与实验值一致;势能面研究表明,顺式、反式构象间的旋转异构化反应容易发生.     

十二时辰中大鼠环核苷酸和白细胞计数的变化

本实验分别在子、丑、寅、卯、辰、巳、午、未、申、酉、戍、亥十二个时辰中,系统地观察了血浆cAMP和cGMP含量以及血液淋巴细胞、嗜中性粒细胞、嗜酸性粒细胞和单核细胞的计数变化,结果表明,它们在十二个时辰中,均反映出阴阳对立和消长的变化规律,在探索“阴阳学说”物质基础的理论和临床上均具有重要意义。     

腺苷生产菌株的回复突变和性质检验

腺苷具有重要的医学价值,由RNA降解获取腺苷成本极高,用微生物发酵法生产腺苷具有重大的经济意义.作为腺苷的生产菌株,黄嘌呤缺陷型的枯草芽孢杆菌如果在生产过程中发生回复突变将会降低腺苷产量.本实验研究了枯草杆菌的黄嘌呤缺陷性菌株是否会回复突变、以及突变菌株的各种性质,进行了V.P.,硝酸盐,高盐浓度,淀粉水解检验,以及进一步的IMP脱氢酶、黄嘌呤氧化酶、腺苷脱氨酶的活性分析,发现大量菌株发生回复突变,该缺陷型菌株遗传非常不稳定,这些突变菌株与生产菌株相比,IMP脱氢酶活发生显著变化,黄嘌呤氧化酶与腺苷脱氨酶的活力没有明显变化.     

乙醇对雄性大鼠睾丸、附睾、血清睾酮和血浆cAMP水平的影响

利用含15％和35％乙醇的水溶液作为雄性大鼠的饮用水,观察了乙醇对雄性性器官及血清睾酮和血浆c AMP水平的影响。结果表明,乙醇对附睾重及血清睾酮水平均具有较强的抑制作用,对血清睾酮水平的抑制作用存在剂量依赖关系。同时,血浆cAMP水平也受到抑制,但不存在剂量依赖关系。实验结果提示,乙醇可能是通过降低血清睾酮水平而实现对附睾的抑制作用,而乙醇通过抑制cAMP可能是导致血清睾酮水平下降的机理之一。     

TNF-α upregulates adenosine 2b (A2b) receptor expression and signaling in intestinal epithelial cells: a basis for A2bR overexpression in colitis

Adenosine is an endogenous signaling molecule upregulated during inflammatory conditions. Acting through the A2b receptor (A2bR), the predominant adenosine receptor in human colonic epithelia, adenosine has been directly implicated in immune and inflammatory responses in the intestine. Little is known about expression and regulation of A2bR during inflammation. Tumor necrosis factor alpha (TNF-α) is highly upregulated during chronic and acute inflammatory diseases. This study examined the expression of A2bR during colitis and studied effects of TNF-α on A2bR expression, signaling and function. Results demonstrated that A2bR expression increases during active colitis. TNF-α pretreatment of intestinal epithelial cells increased A2bR messenger RNA and protein expression. TNF-α significantly increased adenosine-induced membrane recruitment of A2bR and cyclic adenosine monophosphate downstream signaling. Further, TNF-α potentiated adenosine-induced shortcircuit current and fibronectin secretion. In conclusion, we demonstrated that TNF-α is an important regulator of A2bR, and during inflammation, upregulation of TNF-α may potentiate adenosine-mediated responses. Received 21 July 2005; received after revision 22 August 2005; accepted 19 September 2005 †These authors contributed equally to this work.     

RP-HPLC法测定肤痒胶囊中腺苷的含量

采用反相高效液相色谱(RP-HPLC)法,Kromasil ODS-1柱,乙腈-水为流动相,流速1.0 mL/min,柱温25℃,检测波长260 nm,建立了肤痒胶囊中腺苷的含量测定方法.结果显示,腺苷的检测线性范围是0.021~0.525 mg/mL,回归方程为A=331.9×105ρ 2.78×105,相关系数r为0.999 5,回收率为99.55%,相对标准偏差为0.64%.因此,用HPLC法测定腺苷的含量,简便、快速、准确、可靠,可用于肤痒胶囊的质量控制.     

从香菇发酵醪液中分离鸟苷酸技术的研究

香菇发酵醪处理液经７３２阳树脂在ｐＨ２．５￣３．０时得５＇－ＧＭＰ和５＇－ＣＭＰ混合液，再调至ｐＨ４．０￣４．５上７１７阴离子树脂柱，５＇－ＧＭＰ被吸附，用ψ＝３％ＮａＣｌ溶液解吸，即分离得５＇－ＧＭＰ。醪液经０．２μｍ胶体磨破壁后分别作了自溶，酶解（５＇－磷酸二脂酶）和自溶加酶解三种处理，结果５＇－ＧＭＰ得率分别为９４．０％，９５．１％和９５．０％，未见显著差异。     

Role of adenosine A1 and A2 receptors in the regulation of aldosterone production in rat adrenal glands

Summary To investigate the roles of adenosine A₁ and A₂ receptors in the regulation of aldosterone production, we examined the effects of adenosine and adenosine agonists (N⁶-cyclohexyl adenosine; selective adenosine A₁ receptor agonist and 5-N-ethylcarboxamine adenosine; selective adenosine A₂ receptor agonist) on aldosterone and cyclic AMP production in rat adrenal capsular cells. Neither adenosine nor 5-N-ethylcarboxamine adenosine caused significant effects on basal aldosterone or cyclic AMP production. Also, adenosine (10^–3M) showed no consistent effects on aldosterone and cyclic AMP production induced by ACTH. On the other hand, N⁶-cyclohexyl adenosine exhibited a significant inhibition of basal aldosterone and cyclic AMP production at doses of 10^–4 M and 10^–3 M; furthermore, 10^–3 M N⁶-cyclohexyl adenosine inhibited aldosterone and cyclic AMP production stimulated by ACTH. These results suggest that adenosine A₁ receptors are coupled to and inhibit adenylate cyclase and may be involved in the inhibition of aldosterone production.