小檗碱的结构改造及其药理活性的研究进展

小檗碱是从中草药黄连等植物中提取并分离得到的一类异喹啉类生物碱。近年来合成了大量小檗碱衍生物,并且发现了广泛的生理功能,其潜在的结构改造和开发应用价值很大。笔者对这些文献进行了较为系统的分析和整理,通过小檗碱不同位点的衍生物所展现的丰富的药理活性,为以小檗碱作为先导物进行的结构改造及创新药物提供了比较系统的信息。     

两种二氢吡啶衍生物的合成和降压活性

两种二氢吡啶衍生物的合成和降压活性张三奇１）（第四军医大学西京医院药剂科，西安７１００３２）招明高冯锐２）梅其炳赵德化（第四军医大学药理学教研室，西安７１００３２）关键词二氢吡啶衍生物；合成；降压活性１，４二氢３，５吡啶二羧酸酯类化合物是一类重要...     

Side reactions in the pyroglutamic acid-7-amino-4-methylcoumarin synthesis

N-Formylpyroglutamic acid-7-amido-4-methylcoumarine and pyroglutamyl-pyroglutamic acid-7-amido-4-methylcoumarin are the major products in the synthesis of pyroglutamic acid-7-amido-4-methylcoumarin by phosphorus pentachloride in dimethylformamide and dicyclohexylcarbodiimide under pyridine activation. © Munksgaard 1996.     

The Preparation and Acute Antihypertensive Effects of a Nanocapsular Form of Darodipine,a Dihydropyridine Calcium Entry Blocker

We have addressed two problems associated with the use of dihydropyridine calcium entry blockers in antihypertensive therapy, namely, potent vasodilation and short half-lives, by incorporating the representative blocker, darodipine, into a nanocapsular vehicle. In awake, renovascular hypertensive rats, darodipine nanocapsules lowered blood pressure when given orally or intramuscularly, and the initial fall in blood pressure was less marked than that observed with the same dose of darodipine dissolved in polyethylene glycol 400 (PEG). Intramuscular administration of the nanocapsular form of darodipine had an antihypertensive effect which lasted for at least 24 hr.     

Flutamide inhibits nifedipine‐ and interleukin‐1β‐induced collagen overproduction in gingival fibroblasts

Lu H‐K, Tseng C‐C, Lee Y‐H, Li C‐L, Wang L‐F. Flutamide inhibits nifedipine‐ and interleukin‐1β‐induced collagen overproduction in gingival fibroblasts. J Periodont Res 2010; 45: 451–457. © 2010 John Wiley & Sons A/S Background and Objective: To understand the role of the androgen receptor in gingival overgrowth, the effects of flutamide on interleukin‐1β‐ and nifedipine‐induced gene expression of connective tissue growth factor (CTGF/CCN2) and collagen production in gingival fibroblasts were examined. Material and Methods: Gingival fibroblasts from healthy subjects and patients with dihydropyridine‐induced gingival overgrowth (DIGO) were used. Confluent cells were treated with nifedipine, interleukin‐1β or both. The mRNA expression was examined using real‐time polymerase chain reaction, and the concentration of total soluble collagen in conditioned media was analysed by Sircol Collagen Assay. In addition, the protein expressions of androgen receptor, CTGF/CCN2 and type I collagen in gingival tissue were determined by western blot. Results: Interleukin‐1β was more potent than nifedipine in stimulating CTGF/CCN2 and procollagen α1(I) mRNA expression, and there was an additive effect of the two drugs. Healthy cells exhibited an equal or stronger response of procollagen α1(I) than those with DIGO, but DIGO cells displayed a stronger response in the secretion of soluble collagen in the same conditions. Flutamide, an androgen receptor antagonist, inhibited stimulation by nifedipine or interleukin‐1β. Additionally, the protein expressions of androgen receptor and type I collagen were higher in DIGO gingival tissue than those in healthy gingival tissue. Conclusion: The data suggest that both nifedipine and interleukin‐1β play an important role in DIGO via androgen receptor upregulation and that gingival overgrowth is mainly due to collagen accumulation. Flutamide decreases the gene expression and protein production of collagen from dihydropyridine‐induced overgrowth cells.     

Effect of the digitoxigenin derivative, INCICH-D7, on Na+, K+-ATPase

Compound 14beta,17beta-cycloketoester-3beta-OH androstane (INCICH-D7) is a semisynthetic product of a structural modification of the digitoxigenin molecule. INCICH-D7 has a heterocyclic ketoester type fusion between positions C14 and C17 of the steroid nucleus, which confers this molecule stronger electronegativity than that of digitoxigenin. INCICH-D7 retained positive inotropic effect, with a greater safety margin, when compared to digitoxigenin and ouabain. In this study we have examinated the INCICH-D7 effect on Na+, K+-dependent adenosinetriphosphatase (Na+, K+-ATPase) and compared these results with the ones observed with digitoxigenin and ouabain. The inhibitory effect of INCICH-D7 on Na+, K+-ATPase was five times lower (IC50=4 microM) than that of ouabain (IC50=0.8 microM) and 70 times lower than that of digitoxigenin (IC50=0.06 microM). The inhibitory effect of INCICH-D7 and ouabain on the enzyme was irreversible while digitoxigenin's one was reversible in up to an 80%. Our results indicate that inclusion of the heterocycle between positions C14 and C17 in the digitoxigenin molecule lowers significantly the inhibitory effect on Na+, K+-ATPase and renders the interaction between INCICH-D7 and enzyme irreversible under the studied reaction conditions.     

New antithrombotics with an indazole structure

Fifteen new indazole derivatives have been synthesized. In the Born test, compounds (4f) and (4g) were most active. They inhibited the blood platelet aggregation induced by collagen with an IC(50) = 85 or 90 microM, respectively. After oral administration to rats (60 mg/kg) three of the compounds significantly inhibited the formation of thrombi in arterioles and venules. The strongest effect was observed with (4j) which showed an inhibition of 15% in arterioles and 7% in venules. Further experiments showed that compound (4j) does not mediate these effects by activating soluble guanylate cyclase, but likely by inhibiting phosphodiesterase isoform PDE 5.     

二氢吡啶类钙拮抗剂对多柔比星肾毒性的影响

目的观察二氢吡啶类钙拮抗剂对多柔比星(Dox)肾毒性的影响。方法Dox单次6.5 m.gkg-1尾静脉注射诱导大鼠肾损伤,造模后次日大鼠分别ig硝苯地平15 m.gkg-1.d-1,尼群地平10 m.gkg-1.d-1,氨氯地平5 m.gkg-1.d-1,连续30 d,于给药后d 10,20和30收集各组大鼠24 h尿液测尿蛋白含量,于末次给药4 h后处死大鼠,测血清尿素氮和肌酐含量,测肾皮质还原型谷胱甘肽(GSH),丙二醛(MDA),一氧化氮(NO)含量及谷胱甘肽-S-转移酶(GST),过氧化物歧化酶(SOD),一氧化氮合酶(NOS)活性。结果硝苯地平组大鼠于给药d 10和d 20对Dox肾毒性的尿蛋白有增加作用,给药d 30时,对尿蛋白,血清尿素氮和肌酐均无明显影响,对肾组织GSH,MDA,NO含量及GST,SOD,NOS活性也无明显改变;尼群地平组大鼠于给药d 10,20和30时,对Dox肾毒性的尿蛋白及血清尿素氮和肌酐含量均有升高作用,并明显增加肾组织MDA,NO含量及NOS活性,显著降低GSH含量及GST,SOD活性;氨氯地平对Dox所致的尿蛋白,血清尿素氮和肌酐含量的升高具有降低作用,并明显降低肾组织MDA,NO含量及NOS活性,显著增加GSH含量及GST,SOD活性。结论硝苯地平对Dox肾毒性无明显影响,尼群地平则有加重作用,氨氯地平对Dox肾毒性具有保护作用。     

Development of L-type calcium channels and a nifedipine-sensitive motor activity in the postnatal mouse spinal cord

Intrinsic membrane properties are important in the regulation of motoneuronal output during such behaviours as locomotion. A conductance through L-type calcium channels has been implicated as an essential component in the transduction of motoneuronal input to output during locomotion. Given the developmental changes in calcium currents occurring postnatally in some neurons, and the increasing interest in the study of spinal locomotor output in neonatal preparations, experiments were conducted to investigate the postnatal development of L-type calcium channels in mouse motoneurons. This was assessed both physiologically, using a chemically induced rhythmic motor output, and anatomically, using immunohistochemical methods. The electrophysiological data were obtained during rhythmic bursting produced by application of N-methyl-D-aspartate (NMDA) and strychnine to the isolated spinal cord at various postnatal ages. The L-type calcium channel blocker nifedipine has no effect on this ventral root bursting in postnatal day (P) P2-P5 animals, but reversibly reduced the amplitude and/or burst duration of this activity in animals greater than P7. The immunohistochemical evidence demonstrates a dramatic change in the cellular profile of both the alpha1C and alpha1D subunits of L-type calcium channels during postnatal development; the labelling of both subunits increases with age, approximating the adult pattern by P18. These results demonstrate that in the spinal cord, the L-type calcium channel profile develops both physiologically and anatomically in the early postnatal period. This development parallels the development of the mature functional behaviours of weight bearing and walking, and may be necessary for the production of complex motor behaviour in the mature mammal.