Capsaicin-like activity of some natural pungent substances on peripheral endings of visceral primary afferents

Summary 1. The effects of some naturally occurring pungent substances, piperine, mustard oil, eugenol and curcumin, were compared to those of capsaicin in the rat isolated urinary bladder. 2. All test compounds dose-dependently contracted the rat bladder and produced desensitization toward capsaicin (1 mol/l). Development of cross-tachyphylaxis among the natural pungent substances on one hand and capsaicin on the other, suggested a common site of action on visceral primary afferents. 3. Contractile responses to piperine, mustard oil and eugenol were partially tetrodotoxin and ruthenium red-sensitive, suggesting that activation of sensory terminals by these agents takes place indirectly, as well as by a direct action on sensory receptors. 4. The presence of the secondary acylamide linkage (present in the backbone of capsaicin, but not in that of test compounds) does not appear to be essential to produce desensitization of sensory nerve terminals. Send offprint requests to R. Patacchini at the above address     

胡椒碱胶囊自乳化释药系统的处方筛选及体外质量评价

摘 要 目的： 研究胡椒碱自乳化释药系统的处方及其体外特性。方法: 通过溶解度、处方配伍试验以及伪三元相图的绘制来筛选处方,并考察空白处方、含药处方对自乳化效率的影响以及自乳化后乳滴的粒度分布,考察了胡椒碱自乳化胶囊的溶出速率和稳定性。结果: 胡椒碱自乳化胶囊的最终处方为油酸乙酯、Tween 80、Transcutol P,三者之比为30∶55∶15（w∶w∶w）,药物为辅料总量的2.5%,粒径约为90 nm,胡椒碱自乳化胶囊60 min溶出度是自制的胶囊剂6倍;低温和常温稳定性考察药物含量无明显变化。结论:所制备的胡椒碱自乳化胶囊自乳化效率高、能力强、性质稳定,体外溶出率高。     

胡矾口腔膜的质量标准

目的建立胡矾口腔膜的质量标准.方法采用薄层色谱法鉴别胡矾口腔膜中苦参、当归及冰片;用高效液相色谱法测定胡矾口腔膜中胡椒碱含量.结果TLC鉴别方法准确,专属性强;胡椒碱的线性范围为2.5～80μg·ml-1(r=0.9996),平均回收率为98.7%,RSD为1.8%n=5).结论所建立的方法可靠、准确、专属性强,可有效控制胡矾口腔膜的质量.     

Studies on Effect of Piperine on Oral Bioavailability of Ampicillin and Norfloxacin

Ampicillin and Norfloxacin are used to treat variety of bacterial infections. These two drugs have low oral bioavailability. Co-administration of Piperine (20mg/kg), an alkaloid from Piper nigrum L. enhanced oral bioavailability of Ampicillin and Norfloxacin in animal model. This is reflected in various pharmacokinetic measurements like Cmax, Tmax, AUC and t½ of the above antibiotics in animal model.     

RP-HPLC内标法测定蒙成药孟克哈日根钠-7中胡椒碱的含量

目的：建立孟克哈日根钠-7中总胡椒碱的含量测定方法。方法：采用反相高效液相色谱法,色谱主为C18柱,以甲醇-水（77：23）流动相,流速：1．0mL／min,检测波长为343nm。结果：胡椒碱在0．02016-0．2016μg范围内呈良好的线性关系,r=0．9996。平均回收98．8％,RSD为0．53％结论：实验所用方法专属性强、重现性好、精密度高,能准确地对胡椒碱进行含量测定。     

HPLC法测定蒙药森木吉德吉德中胡椒碱的含量

目的：建立森木吉德吉德含量测定方法。方法：采用反相高效液相色谱法测定含量：C18（250mm×4．6mm,5μ）柱,乙腈——水（60：40）为流动相,检测波长为343nm,流速为0．8ml／min。结果：胡椒碱分离完全,加样回收率为99．01％,RSD为1．87％（n=9）。结论：本方法准确、重现性好,可作为森木吉德吉德质量控制方法。     

胡椒碱抑制兔胆结石形成的作用和机制

目的　观察胡椒碱对新西兰兔胆囊结石形成的预防作用和机制。方法　 (1)动物模型 :新西兰兔 30只 ,随机分成 :对照组 (10只 ) ,喂普通饮食 ;结石组 (10只 ) ,喂含 1 2 g/d胆固醇的成石饮食 4周 ,胡椒碱组 (10只 ) ,同时喂饲含 1 2 g/d胆固醇和 0 0 4 5 g/d的胡椒碱饮食 4周。 (2 )氨肽酶N(APN)表达 :利用RT PCR方法 ,检测肝APNmRNA水平的变化。 (3)APN活性 :用化学法检测。结果　结石组 6只 (6 / 10 )出现胆囊结石 ,9只 (9/ 10 )出现胆固醇结晶 ,胡椒碱组和对照组无结石及结晶出现 ;结石组APNmRNAIOD比值 (对照组 0 6 5± 0 18,结石组 1 0 8± 0 35 ,胡椒碱组 0 87±0 4 4 ) ,APN活性 (对照组 6 1± 2 5 3U/L、结石组 2 3 6 4± 10 36U/L ,胡椒碱组 8 31± 6 4 7U/L)明显高于对照组和胡椒碱组。结论　以上结果表明胡椒碱主要通过降低肝APN的表达及胆汁APN酶的活性 ,抑制APN的促成石作用而预防胆固醇结石的形成。     

Pharmacological study on piperine

Systematic pharmacological studies on piperine have revealed that this compound elicited diverse pharmacological activities; CNS depressant activity characterized by antagonism against electroshock seizure and by muscle relaxant activity in mice; antipyretic activity in typhoid vaccinated rabbits; analgesic activity as evaluated by tail-clip pressure and writhing syndrome in mice; antiinflammatory activity in carrageenin-induced edema in rats.     

Modulation of cadmium induced alterations in murine thymocytes by piperine: oxidative stress, apoptosis, phenotyping and blastogenesis

Piperine, a main component of Piper longum Linn. and Piper nigrum Linn., is a plant alkaloid with a long history of medicinal use in Indian medicine. It is known to exhibit a variety of biological activities which include anti-pyretic, anti-inflammatory, anti-depressant, hepatoprotective and antitumor. Its immunomodulatory role has so far been limited to humoral response. The influence of piperine on murine thymocytes, immunocompromised by cadmium has been reported by us in this investigation. The various biochemical parameters such as oxidative stress markers (ROS and GSH), Bcl-2 protein expression, mitochondrial membrane potential, caspase-3 activity, DNA damage, blastogenesis and T lymphocyte phenotypes were determined. Cadmium (25 microM) induced apoptosis earliest at 6 h. Alterations in ROS and GSH preceded mitochondrial membrane depolarization and caspase-3 activation followed by apoptosis. The phenotypic changes occurred at 18 h and blastogenesis at 72 h. Various conc. of piperine (1, 10 and 50 microg/ml) when added along with Cd (25 microM) from 1.5 to 72 h, caused a dose and time dependent amelioration in all the cellular events mentioned above. Modulation of oxidative stress has earlier been reported to reduce Cd induced apoptosis in murine lymphocytes. Inhibition of the ROS production and replenishment of GSH by piperine, may in part be responsible for the suppression of downstream cascade of events, i.e. apoptosis, blastogenesis and T lymphocyte phenotyping. The study clearly demonstrated the anti-oxidative, anti-apoptotic, and restorative ability against cell proliferative mitogenic response and phenotypic alterations by piperine, suggesting its therapeutic usefulness in immunocompromised conditions.     

高效液相色谱法测定蒙药荜茇三味散中胡椒碱的含量

目的：建立蒙药荜茇三味散中胡椒碱的含量测定方法.方法：采用高效液相色谱法,色谱柱：C18柱,流动相：甲醇-水（70：30）,检测波长：343nm.结果：胡椒碱在0.03808μg～0.4760μg范围内呈良好的线性关系,加样平均回收率为99.2%,RSD为1.40%.结论：本法可作为该药品的质量标准.