Effects of standardized extracts GK501, from Ginkgo biloba L., G115 from Panax ginseng C. A. Meyer,and their combination,gincosan® (PHL-00701), on the brain levels of biogenic monoamines and on the serum content of prolactin,growth hormone and ACTH

In experiments on old (26 months old) rats, we found that the extracts of Panax ginseng (G115), Ginkgo biloba (GK501) and their combination Gincosan® (PHL-00701) administered orally at two doses for 7 days induced changes in the levels of biogenic monoamines in some brain regions (frontal cerebral cortex, hippocampus, striatum, hypothalamus and pons). The most characteristic change was the increase produced by the two extracts and their combination in the serotonin level in all brain structures except for pons compared with controls. In the hippocampus G115, GK501 and their combination decreased the noradrenaline level. The same doses of G115, GK501 and their combination applied for 7 days to young (3 months old) and old (26 months old) rats caused significant changes in the blood level of prolactin (PRL), growth hormone (GH) and ACTH compared with age-matched controls: both G115 and GK501 decreased the serum level of PRL compared with age-matched controls; the hormone level being high in old controls, in extract-treated rats it became equal to that in young controls; G115 and PHL-00701 greatly increased the serum level of ACTH in both age groups compared with age-matched controls. Under conditions of induced immobilization and cold stress in young rats, the 7-day pretreatment with G115, GK501 and their combination led to significant changes in the blood levels of PRL, GH and ACTH compared with control untreated stressed and unstressed rats.     

Behavioral effects of Ginkgo biloba L., Panax ginseng C.A. Mey. and Gincosan

The behavioral effects of a standardized extract from Panax ginseng roots (G115), of a standardized extract from Ginkgo biloba leaves (GK501) and of their combination (PHL-00701) (Gincosan) were examined in experiments on rats with undisturbed memory and on rats with experimentally-impaired memory (by alcohol or by muscarinic- and dopamine-receptor antagonists), using methods for active avoidance (shuttle-box) and passive avoidance (step-down and step-through). On multiple administration G115, GK501 and PHL-00701 exerted favorable effects on learning and memory. These effects varied with the dose and administration schedules, with the rat strain and with the behavioral method. Based on earlier results, we discuss the role of changes in brain biogenic amines induced by the extracts in their mechanism of action. The present results allow for ranking G115, GK501 and their combination PHL-00701 (Gincosan) among cognition-enhancing (nootropic) drugs.     

Effect of kauranes from Montanoa spp. on rat uterus

The effect of kaurenoic acid (from Montanoa frutescens), grandifloric and kauradienoic acid (from M. tomentosa) and 16α-hydroxy-ent-kauran-19-oic acid and its methyl ester (from M. hibiscifolia) were assayed on the contractions of rat uterus induced by acetylcholine, oxytocin and serotonin. The four kauranes assayed inhibited the contractile activity induced by the three agonists through a mechanism independent of either β₂-adrenergic or H₂-histaminergic receptors present in uterine smooth muscle. Oestrogenized uteri treated with kauradienoic acid underwent histological changes including epithelial flattening and desquamation.© 1997 John Wiley & Sons, Ltd.     

Involvement of the serotonergic system and neuroplasticity in the antidepressant effect of curcumin in ovariectomized rats: Comparison with oestradiol and fluoxetine

Antidepressant drugs are associated with many challenges due to their adverse impacts. Seeking alternatives through medicinal plants could have a great merit in overcoming these deleterious effects. This study was designed to investigate the potential mechanism of curcumin (CUR) in modifying the depression‐like behaviour in ovariectomised (OVX) rats, inference with fluoxetine (FLX) and oestradiol (E₂). The treatments of OVX rats started after 1 month post ovariectomy and proceeded for 1 month. The experimental animals were divided into five groups: sham‐operated, OVX‐, OVX‐FLX (20 mg kg^?1, i.p., daily), OVX‐E₂ (100 μg kg^?1, i.m., every other day), and OVX‐CUR‐ (100 mg kg^?1, p.o., daily) treated groups. The results showed that CUR modulated the depression‐like behaviour using forced swimming test. It improved the serotonin content in many brain regions by upregulating tryptophan hydroxylase‐2 and 5‐hydroxytryptamine_1A,2A receptor messenger RNA (mRNA) and downregulating monoamine oxidase A mRNA in the limbic system. Furthermore, it upregulated aromatase, brain‐derived neurotropic factor mRNA, and extracellular‐regulated kinase 1/2 protein in the limbic system, relative to FLX and E_2, compared with OVX group. In conclusion, CUR appears to be safe and efficient agent as serotonin modulator similar to FLX and neurotrophic agent like E₂, in improving the depression‐like behaviour in OVX rats.     

Antiinflammatory activity and effects on isolated smooth muscle of extracts from different Teucrium species

The present study analyses the antiinflammatory effects and the action on in vitro motility of methanol and dichloromethanol extracts and stems of four Teucrium species (T. flavum, T. cartaginenses, T. buxifolium and T. pumillum). The antiinflammatory activity was tested in the carrageenan-induced paw oedema in rats. T. flavum methanol (200 mg/kg, i.p.) and dichloromethanol (138 mg/kg, i.p.) extracts showed a significant anti-inflammatory effect through the 24 h experimental period and reduced the E_max induced by histamine and serotonin in vitro on guinea-pig ileum and rat uterus respectively. These extracts did not modify the contractile effects induced by acetylcholine on rat duodenum and noradrenaline on rat vas deferens. The methanol extracts of T. pumillum (50 mg/kg, i.p.) and T. buxifolium (26 mg/kg, i.p.) exhibited significant antiinflammatory effects only in the acute phase of the oedema (2 h) without affecting the chronic phase (24 h). In guinea-pig ileum, rat uterus and rat vas deferens, the methanol extract of T. pumillum reduced the maximal effect induced by histamine, serotonin and noradrenaline, respectively, whereas the methanol extract of T. buxifolium lacked any effect on the contractile activity induced by various agonists in vitro. When tested for antiinflammatory activity the methanol (200 mg/kg, i.p.) and dichloromethanol (200 mg/kg, i.p.) extracts of T. cartaginenses did not modify the oedematous response induced by carrageenan administration.     

α1D受体cDNA转染细胞、大鼠主动脉组织及其培养细胞的细胞膜色谱研究

 目的为了增加细胞膜色谱法的选择性和特异性,用细胞膜色谱法分别研究不同浓度药物BMY7378(α_1D-AR亚型高选择性药物)与大鼠主动脉组织、原代培养大鼠主动脉平滑肌细胞和α_1D-AR转染细胞膜色谱柱的生物亲和作用。方法根据大鼠主动脉细胞表达以α_1D-AR占优势,分别构建大鼠主动脉组织匀浆细胞膜色谱柱、培养大鼠主动脉平滑肌细胞膜色谱柱和受体质粒转染所得受体高表达HEK293α_1D细胞膜色谱柱。用细胞膜色谱法研究6种浓度的BMY7378与受体的亲和色谱特性,分别测定其容量因子并进行相关性分析。结果在大鼠主动脉组织制备的细胞膜固定相(cell membranestationary phase,CMSP)上,最小检测到的BMY7378浓度为1.00 mmol·L^-1;在大鼠主动脉平滑肌细胞CMSP上,最小检测到的BMY7378浓度为0.03 mmol·L^-1;在α_1D-AR细胞CMSP上,最小检测到的BMY7378浓度为0.10 mmol·L^-1。结论与组织器官制备的CMSP的传统细胞膜色谱法比较,培养的细胞或细胞株色谱系统具有更高的灵敏度。可扩大细胞膜色谱法的应用范围,试用于受体亚型选择性药物的高效筛选。     

几种表面活性剂对P-gp底物罗丹明123经肠黏膜透过性的影响

 目的观察低浓度表面活性剂聚氧乙烯蓖麻油,Labrasol和聚山梨酯80对肠黏膜P-gp的调控作用。方法使用体外扩散池法评价罗丹明123(R123)经空肠、回肠和结肠黏膜的经时经吸收方向和分泌方向的透过量和透过系数(P_app),并测定不同浓度表面活性剂对R123和荧光素钠(CF)经肠黏膜透过性的影响。R123和CF在接受室中的浓度用荧光分光光度法测定。结果R123经肠道黏膜的透过性存在部位差,即以空肠、回肠和结肠的次序透过性依次减少。另一方面,R123经肠道分泌方向的透过性显著地高于其吸收方向的透过性。低浓度的CEL和Labrasol可显著增强R123经吸收方向的透过性,减少经分泌方向的透过性;而低浓度的聚山梨酯80可显著增强R123经吸收方向的透过性,但对经分泌方向的透过性无显著影响。但实验浓度的表面活性剂对CF的肠道转运没有影响。结论低浓度的聚氧乙烯蓖麻油、Labrasol和聚山梨酯80可通过对P-gp功能的抑制而用于改善受P-gp介导药物的吸收,有望提高此类药物的口服生物利用度。     

Argyreia nervosa (Burm. f.): Receptor profiling of lysergic acid amide and other potential psychedelic LSD-like compounds by computational and binding assay approaches

Ethnopharmacological relevance

The convolvulacea Argyreia nervosa (Burm. f.) is well known as an important medical plant in the traditional Ayurvedic system of medicine and it is used in numerous diseases (e.g. nervousness, bronchitis, tuberculosis, arthritis, and diabetes). Additionally, in the Indian state of Assam and in other regions Argyreia nervosa is part of the traditional tribal medicine (e.g. the Santali people, the Lodhas, and others). In the western hemisphere, Argyreia nervosa has been brought in attention as so called “legal high”. In this context, the seeds are used as source of the psychoactive ergotalkaloid lysergic acid amide (LSA), which is considered as the main active ingredient.

Aim of the study

As the chemical structure of LSA is very similar to that of lysergic acid diethylamide (LSD), the seeds of Argyreia nervosa (Burm. f.) are often considered as natural substitute of LSD. In the present study, LSA and LSD have been compared concerning their potential pharmacological profiles based on the receptor binding affinities since our recent human study with four volunteers on p.o. application of Argyreia nervosa seeds has led to some ambiguous effects.

Material and methods

In an initial step computer-aided in silico prediction models on receptor binding were employed to screen for serotonin, norepinephrine, dopamine, muscarine, and histamine receptor subtypes as potential targets for LSA. In addition, this screening was extended to accompany ergotalkaloids of Argyreia nervosa (Burm. f.). In a verification step, selected LSA screening results were confirmed by in vitro binding assays with some extensions to LSD.

Results

In the in silico model LSA exhibited the highest affinity with a pK_i of about 8.0 at α_1A, and α_1B. Clear affinity with pK_i>7 was predicted for 5-HT_1A, 5-HT_1B, 5-HT_1D, 5-HT₆, 5-HT₇, and D₂. From these receptors the 5-HT_1D subtype exhibited the highest pK_i with 7.98 in the prediction model. From the other ergotalkaloids, agroclavine and festuclavine also seemed to be highly affine to the 5-HT_1D-receptor with pK_i>8. In general, the ergotalkaloids of Argyreia nervosa seem to prefer serotonin and dopamine receptors (pK_i>7). However, with exception of ergometrine/ergometrinine only for 5-HT_3A, and histamine H₂ and H₄ no affinities were predicted.Compared to LSD, LSA exhibited lower binding affinities in the in vitro binding assays for all tested receptor subtypes. However, with a pK_i of 7.99, 7.56, and 7.21 a clear affinity for 5-HT_1A, 5-HT₂, and α₂ could be demonstrated. For DA receptor subtypes and the α₁-receptor the pK_i ranged from 6.05 to 6.85.

Conclusion

Since the psychedelic activity of LSA in the recent human study was weak and although LSA from Argyreia nervosa is often considered as natural exchange for LSD, LSA should not be regarded as LSD-like psychedelic drug. However, vegetative side effects and psychotropic effects may be triggered by serotonin or dopamine receptor subtypes.     

In vitro pharmacological evaluation of the dichloromethanol extract from Schinus molle l.

The pharmacological activity of the dichloromethanol extract of Schinus molle L. (SM-DCM) was analysed in in vitro models. Preincubation of the isolated guinea-pig ileum or rat uterus preparations with the extract (100 μg/mL) abolished the contractile effects of histamine and serotonin respectively. At the same dose, the extract partially reduced the contractile effects of acetylcholine on the isolated rat duodenum. A 10 μg/mL dose showed an inhibitory effect on histamine and serotonin, but not on acetylcholine-induced contractions (NS). No significant effect was found with a 1 μg/mL dose. © 1998 John Wiley & Sons, Ltd.     

地黄饮子对卒中后抑郁大鼠海马5-羟色胺受体的影响

目的:通过观察地黄饮子对卒中后抑郁大鼠5-羟色胺1A受体(5-HT1AR)与5-羟色胺2A受体(5-HT2AR)mRNA水平表达的影响,进一步探讨地黄饮子治疗脑卒中后抑郁的可能作用机制.方法:健康成年SD大鼠60只,雌雄各半,随机分为6组(空白组、模型组、百优解组、地黄饮子高、中、低剂量组)每组10只,除空白对照组每笼饲养5只外(雌雄分开),其余各组均采用单独饲养法,每笼饲养1只.卒中后抑郁模型建立成功后,模型组、氟西汀组和地黄饮子高、中、低剂量组分别以2.0mL蒸馏水、盐酸氟西汀(1.8 mg·kg-1)和地黄饮子(按生药)450,150,75 mg· kg-ig,1次/d,持续用药至行为学检测.在脑卒中后抑郁大鼠模型上,采用实时荧光定量RT-PCR方法,对卒中后抑郁大鼠5-HT1AR与5-HT2AR mRNA水平进行观察.结果:大鼠海马5-HT1AR相对表达水平与空白组(1.12±0.16)比较,模型组(0.23 ±0.13)有显著性差异(P＜0.01);地黄饮子中、高剂量组(0.76 ±0.13,0.75 ±0.11)与模型组比较,有显著性差异(P＜0.05).各组大鼠海马5-HT2AR mRNA表达水平与空白组(1.13 ±0.12)比较,模型组(2.21±0.21)有显著性差异(P＜0.05);地黄饮子高、中剂量组(1.21±0.21,1.25 ±0.26),与模型组比较,有显著性差异(P＜0.05).结论:地黄饮子可能是通过上调5-HT1AR mRNA、下调5-HT2AR mRNA在海马区的表达,达到治疗卒中后抑郁的目的.     

γ-Mangostin increases serotonin 2A/2C, muscarinic, histamine and bradykinin receptor mRNA expression

Aim of the study

γ-Mangostin is a xanthone found in the fruit hulls of Garcinia mangostana L., which have long been used in Southeast Asia as a traditional medicine for the treatment of abdominal pain, dysentery, wound infections, fever and convulsions. Recent studies have revealed that γ-mangostin exhibits a variety of pharmacological activities, including serotonin 2 (5-HT₂) receptor antagonism, anti-inflammatory effects and analgesic effects. To explore the mechanism of γ-mangostin responsible for these pharmacological activities, especially its effects on some related receptors, we investigated the effects of γ-mangostin on 5-HT₂, histamine (H₁) and bradykinin (BK₂) receptor gene expression in neuroblastoma (NG 108-15) cells in vitro. Additionally, to extend the study of the pharmacological properties, we examined the effect of γ-mangostin on the muscarinic (M₄) receptor.

Materials and methods

NG 108-15 cells were cultured in vitro and treated with γ-mangostin or a 5-HT₂ receptor antagonist (either imipramine or ketanserin). Then, the levels of mRNA for 5-HT_2A/2C receptors were evaluated by semi-quantitative RT-PCR. The preventive effect of serotonin on the enhancement effects was also revealed. Additionally, the effects of γ-mangostin on the muscarinic, histamine and bradykinin receptors were determined.

Results

Chronic application of γ-mangostin at a concentration of 0.1 μM induced a significant increase in the level of 5-HT_2A/2C receptor mRNA. These effects were prevented by serotonin. Moreover, γ-mangostin up-regulated the M₄, H₁ and BK₂ receptors.

Conclusion

The ability of γ-mangostin to enhance the expression of 5-HT_2A/2C, muscarinic, histamine and bradykinin receptor mRNA suggests that this compound has antagonistic effects. These pharmacological properties may partly account for the benefits of using mangosteen in the treatment of inflammation, pain and neuropsychiatric symptoms.     

Effect of Ipomoea intrapilosa Methanol Extract on the Serotonergic Response in Rat Uterus

A methanol extract (MEII) obtained from the seeds of Ipomoea intrapilosa and its isolated crude alkaloid fraction (ALKII) were tested as possible blockers of the serotonergic response in the rat uterus in vitro . The results obtained showed an unsurmountable non-selective inhibition of the contractile response induced by serotonin on isolated uterine smooth muscle.     

单向灌流法评价复方龙脉宁汤剂配伍对葛根素肠吸收的影响

建立大鼠在体单向肠灌流模型,采用高效液相色谱法测定灌流液中葛根素的浓度,考察葛根、葛根-穿山龙、葛根-川芎和复方龙脉宁4种汤剂在十二指肠、空肠、回肠和结肠中葛根素的吸收情况。结果显示在十二指肠和回肠中,葛根-穿山龙组与复方龙脉宁组葛根素的吸收参数无显著性差异,但均显著高于葛根和葛根-川芎组的吸收(P0.05);在空肠和结肠中,3个配伍组中葛根素的吸收参数与葛根单药组相比,存在显著性差异(P0.05),而复方龙脉宁组中葛根素的吸收参数与葛根-穿山龙和葛根-川芎组相比也存在显著性差异(P0.05)。表明在大鼠全肠段中,复方龙脉宁汤剂对葛根素的吸收有明显的促进作用。在十二指肠和回肠中,复方中穿山龙对葛根素的吸收有明显的促进作用;在空肠和结肠中,穿山龙和川芎能协同促进葛根素的吸收。     

Pharmacological evaluation of the dichloromethanol extract from Inula crithmoides L.

The pharmacological effect of the dichloromethanol extract of Inula crithmoides L. was analysed in in vitro and in vivo models. The extract dose-dependently decreased arterial blood pressure and furthermore it showed low acute toxicity, CNS depressor activity and analgesic and antiinflammatory effects. Preincubation of the guineapig ileum and rat duodenum (100 μg/mL) produced a significant reduction in the contractile effects of histamine and acetylcholine and a concentration-related inhibition of the effects of serotonin. Following further fractionation the methylene chloride/acetone (50/50) fraction caused a significant decrease in motor activity and significantly reduced the threshold of pain chemical stimulus.     

Thymoquinone-induced relaxation of isolated rat pulmonary artery

Aim of the study

The effect of thymoquinone (TQ), the main constituent of the volatile oil of black seed (Nigella sativa L. family Ranunculaceae), on the isolated rat pulmonary arterial rings was investigated.

Materials and methods

Isolated rat pulmonary arterial rings were precontracted with phenylephrine and concentration–response curves to TQ were constructed. The effects of different receptors antagonists or enzyme inhibitors were examined.

Results

TQ caused a concentration-dependent decrease in the tension of the pulmonary arterial rings precontracted by phenylephrine. The effects of TQ were not influenced by pretreatment of the rings with propranolol (a non-selective β-blocker), atropine (a non-selective blocker for muscarinic receptors), theophylline (an adenosine receptor antagonist), indomethacin (a cyclooxygenase inhibitor), L-NAME (a NO synthase inhibitor), methylene blue (an inhibitor of soluble guanylyl cyclase) and nifedipine (a Ca²⁺ channel blocker). The effects of TQ were significantly potentiated by bosentan (an ET_A/ET_B receptor antagonist). The effects of TQ were slightly abolished by pretreatment of the rings with glibenclamide (a non-selective blocker of ATP-sensitive K+ channels). TQ totally abolished the pressor effects of serotonin and phenylephrine on the isolated rat pulmonary arterial rings.

Conclusion

The results of the present study suggest that TQ-induced relaxation of the precontracted pulmonary artery is probably mediated, at least in part, by activation of ATP-sensitive potassium channels and possibly by non-competitive blocking of serotonin, α1 and endothelin receptors.     

The source of ca2+ for the spasmolytic actions of longicaudatine,a bisindole alkaloid isolated from Strychnos trinervis (Vell.) Mart. (Loganiaceae)

Longicaudatine, a tertiary bisindole alkaloid isolated from the root bark of Strychnos trinervis (Vell.) Mart. (Loganiaceae), antagonized in a noncompetitive manner, carbachol and histamine induced contractions of the guinea-pig ileum and bradykinin responses in the rat uterus. The respective pD₂' values (mean ± SE) were 4.61 ± 0.21, 4.98 ± 0.04 and 4.49 ± 0.01. Longicaudatine, unlike verapamil, had no effect on voltage dependent Ca²⁺ channels, as it failed to inhibit KCI or CaCl₂ induced contractions of guinea-pig ileum and depolarized rat uterus respectively. When compared with sodium nitroprusside, an antagonist of receptor operated Ca²⁺ channels, longicaudatine produced a slower and weaker inhibition of noradrenaline induced sustained contractions of rabbit aortic strips. However, in the aorta, the alkaloid antagonized the intracellular calcium dependent transient contractions of noradrenaline and longicaudatine (IC₅₀, 5.01 × 10^?7 M) was approximately 133 times more potent that procaine (IC₅₀, 6.68 × 10^?5 M), a known inhibitor of the release of Ca²⁺ from intracellular stores. Longicaudatine may exert nonspecific spasmolytic effects by acting on intracellular Ca²⁺ stores, rather than on depolarization dependent or receptor operated Ca²⁺ channels.     

壳寡糖促进岩黄连总碱提取物中原小檗碱型生物碱成分肠道吸收的研究

目的 :考察壳寡糖对岩黄连总碱提取物中原小檗碱型生物碱活性成分肠道吸收的促进作用. 方法 :采用大鼠在体肠单向灌流模型,研究添加不同浓度壳寡糖后岩黄连总碱中脱氢卡维丁、盐酸小檗碱和盐酸巴马汀的吸收动力学参数变化,评价壳寡糖对药物成分肠道吸收的促进作用. 结果 :壳寡糖的浓度对3个活性指标成分在大鼠肠道的吸收速率常数(K_a)和有效渗透系数(P_eff)具有不同程度的影响,在0.5%壳寡糖溶液中活性指标成分的K_a和P_eff增加明显,呈现较强的吸收促进作用. 结论 :壳寡糖对岩黄连生物碱中原小檗碱型生物碱活性成分的肠道吸收有一定促进作用.     

Estrogenic and serotonergic butenolides from the leaves of Piper hispidum Swingle (Piperaceae)

Ethnopharmacological relevance

Our previous work has demonstrated that several plants in the Piperaceae family are commonly used by the Q’eqchi Maya of Livingston, Guatemala to treat amenorrhea, dysmenorrhea, and pain. Extracts of Piper hispidum Swingle (Piperaceae), bound to the estrogen (ER) and serotonin (5-HT7) receptors.

Aim of the study

To investigate the estrogenic and serotonergic activities of Piper hispidum extracts in functionalized assays, identify the active chemical constituents in the leaf extract, and test these compounds as agonists or antagonists of ER and 5-HT7.

Materials and methods

The effects of the Piper hispidum leaf extracts were investigated in estrogen reporter gene and endogenous gene assays in MCF-7 cells to determine if the extracts acted as an estrogen agonist or antagonist. In addition, the active compounds were isolated using ER- and 5-HT7 receptor bioassay-guided fractionation. The structures of the purified compounds were identified using high-resolution LC–MS and NMR spectroscopic methods. The ER- and 5-HT7-agonist effects of the purified chemical constituents were tested in a 2ERE-reporter gene assay in MCF-7 cells and in serotonin binding and functionalized assays.

Results

Three butenolides including one new compound (1) were isolated from the leaves of Piper hispidum, and their structures were determined. Compound 1 bound to the serotonin receptor 5-HT₇ with IC₅₀ values of 16.1 and 8.3 μM, respectively, and using GTP shift assays, Compound 1 was found to be a partial agonist of the 5-HT₇ receptor. The Piper hispidum leaf extracts, as well as Compounds 2 and 3 enhanced the expression of estrogen responsive reporter and endogenous genes in MCF-7 cells, demonstrating estrogen agonist effects.

Conclusions

Extracts of Piper hispidum act as agonists of the ER and 5-HT₇ receptors. Compound 1, a new natural product, identified as 9,10-methylenedioxy-5,6-Z-fadyenolide, was isolated as the 5-HT₇ agonist. Compounds 2 and 3 are reported for the first time in Piper hispidum, and identified as the estrogen agonists. No inhibition of CYP450 was observed for any of these compounds in concentrations up to 1 μM. These activities are consistent with the Q’eqchi traditional use of the plant for the treatment of disorders associated with the female reproductive cycle.     

天麻改善小鼠睡眠作用及其机制研究

目的探讨天麻对小鼠睡眠的促进作用及其对中枢多巴胺(DA)系统的影响,并进一步研究天麻有效成分天麻素通过影响DA通路发挥作用的机制。方法小鼠随机分为对照组、天麻组、橄榄油组、天麻-橄榄油组及阳性对照艾司唑仑组,每组10只,分别ig给予生理盐水、天麻、橄榄油、天麻-橄榄油和艾司唑仑,连续给药20 d。各组小鼠分别在第7、20天给药30～40 min后ip最大阈下剂量戊巴比妥钠(35 mg/kg),测定睡眠发生率;分别在第8天及第21天ip最小阈上剂量戊巴比妥钠(50mg/kg),检测小鼠睡眠潜伏期和睡眠时长;采用ELISA法测定天麻对小鼠脑组织DA水平的影响;采用q RT-PCR法检测天麻对DA受体各亚型表达的影响;构建DA受体D1、D2诱导表达稳定细胞株,Westernblotting法检测ERK通路相关蛋白的表达水平。结果与对照组比较,天麻给药20 d后小鼠睡眠潜伏期显著缩短,睡眠发生率提高,睡眠时长延长,中枢DA水平显著提高,DA受体各亚型的表达水平显著上调。同时,天麻中有效成分天麻素可激活DA受体D2而不是D1介导的信号通路。结论天麻可能通过上调中枢DA系统活性进而调控睡眠,天麻中有效成分天麻素可能通过D2介导的信号通路发挥作用。     

细胞膜色谱法筛选川芎-白芷中5-HT受体激动剂的研究

偏头痛是临床的常见病和多发病,研究表明,5-羟色胺(5-HT)受体在偏头痛的发病中起重要作用。实验通过大鼠纹状体组织制备得到色谱固定相,并利用细胞膜色谱与液相色谱的离线联用来特异性地识别川芎-白芷药对中可与固定相上受体相互作用的配体,发现了欧前胡素是其中潜在的活性成分。以不同浓度(2.42×10-8~4.84×10-7mol·L-1)的5-HT1D受体激动剂舒马普坦为模型药物,记录样品在模型中的容量因子,测得欧前胡素与5-HT1D受体作用的平衡解离常数为(4.59±0.33)×10-6mol·L-1,并采用硝酸甘油致大鼠偏头痛模型验证其药理活性。该研究为体外快速有效地研究药物与受体之间的相互作用提供了一种新方法。