Comparative study of taste disturbance by losartan and perindopril in healthy volunteers

The aim of this study was to compare the degree of taste disturbance by losartan, an angiotensin II receptor blocker, with that of perindopril, an angiotensin-converting enzyme inhibitor. Perindopril erbumine (2 mg), losartan potassium (25 mg), or vehicle was given to Japanese volunteers (n = 7) for 14 days in a randomized, placebo-controlled, 3-way crossover design with a 14-day washout period. Gustometry by filter-paper test and electrogustometry were performed before and at the end of each trial. Plasma renin activity (PRA) and serum and salivary zinc concentrations were measured. One subject dropped out because of a perindopril-induced dry cough, but no one claimed a taste disturbance. Detection thresholds of 4 basic tastes (sweet, salty, sour, and bitter) by the paper-disc test and electrogustometry were significantly worsened, and plasma renin activity was elevated by the drugs, whereas the deteriorating effects of 2 drugs did not significantly differ. These drugs did not affect zinc concentrations in plasma and saliva. It was concluded that losartan and perindopril similarly alter taste sensitivity during repeated dosing of the drugs.     

氯沙坦钾胶囊与片在健康人体的生物等效性

目的评价氯沙坦钾胶囊与片剂(抗高血压药)在健康人体的生物等效性。方法用随机交叉试验设计,20名健康志愿者分别单剂口服氯沙坦钾受试制剂和参比制剂50mg,测定其血药浓度并进行生物等效性的检验。结果受试制剂和参比制剂的Cmax分别为(317.42±217.05),(295.57±132.16)ng·mL-1;tmax分别为(1.17±0.67),(1.27±0.73)h;AUC0-t分别为(637.63±379.83),(591.05±300.77)ng·h·mL-1,2制剂比较无显著性差异。结论氯沙坦钾胶囊与氯沙坦钾片为生物等效性制剂。     

国产雷米普利胶囊在健康人体的药代动力学和相对生物利用度

目的研究健康受试者口服雷米普利胶囊(抗高血压药)的药代动力学和相对生物利用度。方法20名健康受试者随机服用雷米普利受试和参比制剂各10mg,用HPLC-MS/MS法测定血浆中雷米普利和雷米普利拉的浓度。结果主要药代动力学参数,试验与参比制剂中雷米普利的tmax分别为(0.60±0.17),(0.63±0.25)h;Cmax分别为(40.11±14.48),(41.78±13.18)ng·mL-1;t1/2分别为(2.75±1.36),(2.28±1.28)h;AUC0-12分别为(42.09±11.22),(41.81±12.89)ng·h·mL-1;试验制剂的相对生物利用度为(101.47±16.02)%。试验与参比制剂中雷米普利拉的tmax分别为(2.70±0.47),(2.60±0.60)h;Cmax分别为(42.02±12.53),(41.80±14.65)ng·mL-1;t1/2分别为(17.99±6.28),(18.51±5.81)h;AUC0-72分别为(310.65±91.42),(310.21±102.74)ng·h·mL-1。试验制剂的相对生物利用度为(101.09±15.28)%。结论参比与试验制剂具有生物等效性。     

液相色谱-质谱联用法同时测定人血浆中雷米普利和雷米普利拉的浓度

目的:建立同时测定人血浆中雷米普利和雷米普利拉浓度的液相色谱-质谱方法。方法:以喹那普利为内标,血浆样品经固相萃取小柱提取后,采用HPLC-MS(TOF)联用技术,以电喷雾(ESI)作为接口技术,以宽的m/z为数据采集范围检测后,选择准分子离子[M H] 作为检测离子,进行滤过、积分的方式检测,同时测定人血浆中雷米普利和雷米普利拉的浓度。结果:雷米普利和雷米普利拉的线性范围分别为1~80μg·L-1和0.5~40μg·L-1,日内精密度与日间RSD均小于10%。结论:该测定方法具有灵敏、专一和快速的优点,可满足雷米普利在人体内药动学研究的要求。     

氯沙坦和雷米普利对压力过载引起的左心室肥厚作用的比较观察

目的：应用氯沙坦和雷米普利来探讨血管紧张肽Ⅱ对压力过载引起的左心室肥厚的相关作用。方法：采用缩窄大鼠肾动脉间腹主动脉的方法造成后负荷过载所致的左心室肥厚模型。造模后12 wk,分别给予灌服氯沙坦(1.0 mg·kg~(-1))和雷米普利(1.0 mg·kg~(-1))。给药12 wk后,应用形态测量学测定左室重量指数；Langendorff离体心脏灌流法测定离体心功能和右颈总动脉插管法测定在体心功能及血流动力学；应用酶联免疫吸附法测定大鼠血浆血管紧张肽Ⅱ(AngⅡ)、醛甾(固)酮(Ald)含量和心肌组织AngⅡ含量。结果：与模型动物比较,氯沙坦和雷米普利均能降低左室重量指数；在体大鼠血流动力学的测定中发现,压力过载造成大鼠动脉血压和左室收缩压显著升高,应用氯沙坦和雷米普利治疗后,明显改善大鼠心脏收缩功能,降低左室收缩压和外周动脉血压；离体大鼠心功能测定发现,压力过载引起离体大鼠心脏左室舒张压和左室最大上升速率下降,氯沙坦和雷米普利不能改善左室舒张压和左室最大上升速率下降。此外,氯沙坦和雷米普利能够降低心室重构过程中血浆和心肌组织中AngⅡ的含量以及血浆中Ald含量。结论：应用氯沙坦和雷米普利均能够降低缩窄大鼠腹主动脉造成的左心室肥厚,进一步提示AngⅡ在慢性压力过载导致左心室重构中起着关键性作用。     

氯沙坦钾片在健康人体的生物等效性

目的评价2种氯沙坦钾片(血管紧张素Ⅱ受体拮抗药)在健康人体的生物等效性。方法用双交叉设计,24名健康男性志愿者随机分为2组,单剂量口服氯沙坦钾片试验药物或对照药物50 mg,用液相色谱-串联质谱法同时测定血浆中氯沙坦及其活性代谢产物E3174的血药浓度,用BAPP 2.0软件计算药代动力学参数和生物利用度。结果氯沙坦:试验药物与对照药物的Cmax分别为(253.10±155.43),(232.37±136.66)ng.mL-1;Tmax分别为(1.09±0.70),(1.30±0.80)h;t1/2分别为(1.93±0.32),(1.98±0.53)h;AUC0-12分别为(454.19±166.61),(414.97±152.22)ng.h.mL-1,可信区间99.4%～118.6%;试验药物对于对照药物的平均相对生物利用度F为(112.0±29.9)%。E3174:试验药物与对照药物的Cmax分别为(447.45±132.66),(430.81±135.78)ng.mL-1;Tmax分别为(3.56±1.14),(3.77±1.14)h;t1/2分别为(4.55±0.61),(4.67±0.68)h;AUC0-36分别为(3522.17±1162.22),(3307.16±1078.13)ng.h.mL-1,可信区间100.5%～111.8%。试验药物对于对照药物的平均相对生物利用度F为(107.2±16.8)%。结论 2种氯沙坦钾药物具有生物等效性。     

氯沙坦钾胶囊人体生物等效性研究

目的评价氯沙坦钾胶囊与氯沙坦钾片在中国健康成年男性志愿者中的生物等效性。方法20名男性健康受试者按照随机、开放、双周期交叉试验设计,分别单剂量口服试验制剂100 mg或参比制剂100 mg。以HPLC-MS/MS法测定给药后不同时间血浆中氯沙坦钾及其活性代谢产物E-3174的浓度,计算药动学参数,并判断2种制剂是否等效。结果参比制剂中氯沙坦钾的主要药物动力学参数Cmax为(831.2±247.4)μg.L-1,tmax为(1.0±0.4)h,AUC0→8为(1 110.2±266.6)μg.h.L-1,t1/2为(2.1±0.6)h;代谢产物E-3174的Cmax为(1 198.2±301.2)μg.L-1,tmax为(2.0±0.8)h,AUC0→24为(6 838.6±1 921.2)μg.h.L-1,t1/2为(8.5±2.3)h。受试制剂中氯沙坦钾的主要药物动力学参数Cmax为(846.6±216.7)μg.L-1,tmax为(0.7±0.3)h,AUC0→8为(1 097.4±278.7)μg.h.L-1,t1/2为(2.3±0.5)h;代谢产物E-3174的Cmax为(1 166.9±324.6)μg.L-1,tmax为(2.0±0.6)h,AUC0→24为(6 712.4±2 021.6)μg.h.L-1,t1/2为(8.5±1.5)h。结论受试制剂氯沙坦钾胶囊与参比制剂氯沙坦钾片为生物等效制剂。     

Comparative bioavailability of two losartan formulations in healthy human volunteers after a single dose administration

OBJECTIVE: To compare the bioavailability of two potassic losartan immediate release tablet (50 mg) formulations (Losartan from Laboratórios Cristália Ltd., Brazil, as a test formulation and Cozaar from Merck Sharp & Dohme Farmacêutica Ltd., Brazil, as a reference formulation) in 25 volunteers of both sexes. MATERIAL AND METHODS: The study was conducted in an open, randomized, 2-period crossover design and a 1-week washout period. Plasma samples were obtained over a 24-hour interval. The concentrations of losartan and its active metabolite losartan acid were analyzed by combined reversed phase liquid chromatography and tandem mass spectrometry (LC-MS-MS) with negative ion electrospray ionization using a selected ion monitoring method. From the losartan and losartan acid plasma concentrations vs. time curves the following pharmacokinetic parameters were obtained: AUClast, AUC0-inf and Cmax. RESULTS: The geometric mean and respective 90% confidence interval (CI) of Losartan/Cozaar losartan percent ratios were 92.9% (82.2-105.0%) for Cmax, 99.0% (92.5-105.9%) for AUClast, and 99.1% (92.7-105.8%) for AUC0-inf. Furthermore, the geometric mean and respective 90% CI of Losartan/Cozaar losartan acid percent ratios were 98.5% (91.5-106.0%) for Cmax, 97.9% (93.3 102.7%) for AUClast, and 98.1% (93.6-102.9%) for AUC0-inf. CONCLUSION: Since the 90% CI for Cmax, AUClast and AUC0-inf were within the 80-125% interval proposed by the US Food and Drug Administration, it was concluded that the potassic losartan immediate release 50 mg tablet was bioequivalent to the Cozaar immediate release 50 mg tablet, according to both the rate and extent of absorption. While there were no significant differences in the bioequivalence assessed by either losartan or losartan acid, future bioequivalence studies on losartan may be performed by quantifying losartan alone as the parent compounds are more discriminative.     

Comparative bioavailability of two ramipril formulations after single-dose administration in healthy volunteers

OBJECTIVE: To assess the bioequivalence of a ramipril 5 mg tablet formulation (ramipril test formulation from Laboratórios Biosintética Ltda (Sao Paulo, Brazil) and Triatec from Aventis Pharma (Sueano, Brazil) standard reference formulation) in 26 healthy volunteers of both sexes. METHODS: The study was conducted using an open, randomized, 2-period crossover design with a 2-week washout interval. Plasma samples were obtained over a 36-hour period. Plasma ramipril and ramiprilat concentrations were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS) with positive ion electrospray ionization using multiple reaction monitoring (MRM). From the ramipril and ramiprilat plasma concentration vs. time curves, the following pharmacokinetic parameters were obtained: AUClast, AUCinf and Cmax. RESULTS: The limit of quantification was 0.2 ng x ml(-1) and 1.0 ng x ml(-1) for ramipril and ramiprilat, respectively. The geometric means and 90% confidence intervals (CI) for Ramipril/Triatec and Ramiprilat/Triatec percent ratios were: 104.69% (90% CI = 93.21-117.59%) for Cmax, 102.49% (90% CI = 92.76-113.24%) for AUClast, 103.60% (90% CI = 93.56 114.73%) for AUCinf, 108.48% (90% CI = 98.86-119.03%) for Cmax, 105.88% (90% CI = 101.55-110.39%) for AUClast, 97.30% (90% CI = 90.17-104.99%) for AUCinf, respectively. CONCLUSION: Since the 90% CI for AUClast, AUCinf and Cmax ratios were within the 80-125% interval proposed by the U.S. FDA, it was concluded that the ramipril formulation produced by Laboratórios Biosintética Ltda is bioequivalent to the Triatec formulation in both rate and extent of absorption.     

氯沙坦及其代谢物在蒙古族和汉族健康人体的药动学特征

目的研究蒙古族和汉族健康受试者口服单剂量氯沙坦钾片的药动学特征。方法健康受试者20名（其中蒙古族10名,汉族10名,男女各半）,口服单剂量氯沙坦钾片50mg;用HPLC荧光法测定氯沙坦及其代谢物E-3174血药浓度,DAS软件程序进行数据处理并采用SPSS软件进行统计学分析。结果蒙古族受试者单剂量口服50nag氯沙坦钾片剂后氯沙坦和E-3174的主要药动学参数分别为：ρmax（438±254）、（358±169）μg·L-1;tmax（1．6±0．9）、（3．8±1．9）h;t1/2（1．9±1．2）、（4．4±0．7）h;AUC024（859±309）、（2516±652）P-g·h·L-1;AUC0→∞（944±338）、（2603±668）μg·h·L-1。汉族受试者氯沙坦和E-3174的主要药动学参数分别为：ρmax（351±168）、（242±60）μg·L-1;tmax（1．4±1．1）、（3．6±1．7）h;t1/2（0．8±0．4）、（4．7±1．1）h;AUC0→24（497±172）、（1853±194）μg·h·L-1;AUC0→∞（523±184）、（1960±182）μg·h·L-1。结论氯沙坦钾片剂在蒙古族和汉族健康受试者体内药动学参数差异存在统计学意义,个体间药动学参数存在较大差异,临床治疗中应实行个体化给药方案,在不同性别间药动学参数差异无统计学意义。     

氯沙坦及其代谢物在维吾尔族和汉族健康志愿者的药代动力学

目的 研究维吾尔族和汉族健康受试者单剂量口服氯沙坦钾片(抗高血压药)的药代动力学特征.方法 20名健康受试者(其中维吾尔族10名,汉族10名,男女各半),单剂量口服氯沙坦钾片50 mg;用高效液相色谱-荧光法测定氯沙坦及其代谢物E-3174血药浓度,用DAS软件进行数据处理、SPSS 13.0软件进行统计学分析.结果 维吾尔族受试者单剂量口服氯沙坦钾片50 mg后氯沙坦和代谢物E-3174的主要药代动力学参数分别为:Cmax(344±153),(477±166)μg·mL-1;tmax(1.0±0.3),(2.6±0.5)h;t1/2(1.0±0.4),(2.9±0.8)h;AUG0-24h(598±216),(2243±518)μg·h·mL-1;AUC0-∞(632±242),(2429±552)μg.h·mL-1.汉族受试者单剂量口服氯沙坦钾片50 mg后氯沙坦和代谢物E-3174的主要药代动力学参数分别为:Cmax(351±168),(242±60)ng·mL-1;tmax(1.4±1.1),(3.6±1.7)h;t1/2(0.8±0.4),(4.7±1.1)h;AUC0-24h(497±172),(1853±194)ng·h·mL-1;AUC0-∞(523±184),(1960±182)ng·h·mL-1.结论 氯沙坦的代谢物E-3174的药代动力学参数t1/2、Vd、Cmax在维吾尔族和汉族健康受试者间的差异有显著性意义(P＜0.05),不同性别间药代动力学参数的差异无显著性意义(P＞0.05),所有药代动力学参数在同一民族和不同民族的个体间差异都很大,临床治疗中应实行个体化给药方案.     

氯沙坦及其代谢物在朝鲜族和汉族健康人体内的药代动力学

目的:研究朝鲜族和汉族健康受试者口服单剂量氯沙坦钾片的药代动力学.方法:健康受试者20名(朝鲜族10名,汉族10名,男女各半),口服单剂量氯沙坦钾片剂50mg;用HPLC-荧光法测定氯沙坦及其代谢物E-3174血药浓度,采用DAS软件和SPSS软件进行数据处理和统计学分析.结果:单剂量口服50 mg氯沙坦钾片后,朝鲜族受试者的氯沙坦和E-3174的主要药动学参数如下:Cmax分别为(524±349),(493±188)ng·mL-1;tmax分别为(0.9±0.4),(2.4±0.8)h;t1/2(1.5±0.4),(3.1±0.7)h;AUC0-24分别为(682±319),(2563±752) ng·h·mL-1;AUC0-∞分别为(752±331),(2608±766)ng·h·mL-1.汉族受试者的氯沙坦和E-3174的主要药动学参数如下:Gmax分别为(351±168),(242±60)ng·mL-1;tmax分别为(1.4±1.1),(3.6±1.7)h;t1/2分别为(0.8±0.4),(4.7±1.1)h;AUC0-24分别为(498±172),(1853±194) ng·h·mL-1;AUC0-∞分别为( 523±184),(1960±182) ng-h·mL-1.结论:氯沙坦钾片在朝鲜族和汉族健康受试者体内药动学参数差异存在统计学意义,在不同性别间药动学参数差异无统计学意义,个体间药动学参数存在较大差异,临床治疗中应实行个体化给药方案.     

氯沙坦钾胶囊及其片剂在健康人体的生物等效性研究

目的:研究氯沙坦钾胶囊及其片剂在健康人体内的药动学特征,并评价两种制剂间的生物等效性.方法:20名健康男性志愿受试者随机交叉单剂量口服试验制剂和参比制剂50 mg,清洗期1周,LC-MS/MS法测定血浆氯沙坦和代谢物氯沙坦羧酸(E-3174)浓度.药代参数的计算与统计分析使用DAS2.0软件.结果:口服试验制剂和参比制剂后,受试者的氯沙坦和E-3174主要药代动力学参数如下:氯沙坦Cmax分别为(183.83±91.30),(176.45±93.97) μg·L-1;AUC0-t分别为(333.18±105.00),( 323.75±101.92) μg·h·L1;AUC0-∞分别为(344.88±104.15),(341.32±106.13) μg·h·-1;t1/2分别为(1.84±0.52),(1.99±0.60)h;tmax分别为(0.70±0.22),(0.98±0.62)h.E-3174 Cmax分别为(344.85±114.33),(329.95±106.42) μg·L-1;AUC0-t分别为(2 445.09±608.97),(2 332.54±564.72) μg·h·L-1;AUC0-∞分别为(2 503.45±612.62),(2 390.92±567.03) μg·h·L-1;t1/2分别为(4.17±0.49),(4.13±0.66)h;tmax分别为(3.14±0.72),(3.39±0.96)h.试验制剂氯沙坦钾胶囊中氯沙坦和E-3174相对生物利用度分别为( 104.9±20.7)％和(105.2±12.1)％.结论:本试验采用的氯沙坦钾胶囊和氯沙坦钾片为生物等效制剂.     

Modulation of cold pressor-induced stress by shavasan in normal adult volunteers

Shavasan is known to enhance one's ability to combat stressful situations. The present study was planned to determine if shavasan could modulate the physiological response to stress induced by cold pressor test (CPT) and the possible mechanisms involved. Ten normal adults were taught shavasan and practiced the same for a total duration of seven days. RR interval variation (RRIV), deep breathing difference (DBD), and heart rate, blood pressure & rate-pressure-product (RPP) response to CPT were measured before and immediately after shavasan. Shavasan produced a significant increase in DBD and an appreciable but statistically insignificant increase in RRIV suggesting an enhanced parasympathetic activity. Significant blunting of cold pressor-induced increase in heart rate, blood pressure and RPP by shavasan was seen during and even five minutes after CPT suggesting that shavasan reduces the load on the heart by blunting the sympathetic response. It is concluded that shavasan can enhance one's ability to withstand stress induced by CPT and this ability can be achieved even with seven days of shavasan training.     

Modulation of visceral pain and inflammation by protease-activated receptors

The gastrointestinal (GI) tract is exposed to a large array of proteases, under both physiological and pathophysiological conditions. The discovery of G protein-coupled receptors activated by proteases, the protease-activated receptors (PARs), has highlighted new signaling functions for proteases in the GI tract, particularly in the domains of inflammation and pain mechanisms. Activation of PARs by selective peptidic agonists in the intestine or the pancreas leads to inflammatory events and changes in visceral nociception, suggesting that PARs could be involved in the modulation of visceral pain and inflammation. PARs are present in most of the cells that are potentially actors in the generation of irritable bowel syndrome (IBS) symptoms. Activation of PARs interferes with several pathophysiological factors that are involved in the generation of IBS symptoms, such as altered motility patterns, inflammatory mediator release, altered epithelial functions (immune, permeability and secretory) and altered visceral nociceptive functions. Although definitive studies using genetically modified animals, and, when available, pharmacological tools, in different IBS and inflammatory models have not yet confirmed a role for PARs in those pathologies, PARs appear as promising targets for therapeutic intervention in visceral pain and inflammation processes.     

Bioequivalence study of two losartan formulations administered orally in healthy male volunteers

The bioavailability of a new losartan preparation (2-butyl-4-chloro-1-[p-(o-1H-tetrazol-5-ylphenyl)benzyl]imidazole-5-methanol monopotassium salt, CAS 114798-26-4) was compared with the reference preparation of the drug in 24 healthy male volunteers, aged between 19 and 32. The open, randomized, single-blind two-sequence, two-period crossover study design was performed. Under fasting conditions, each subject received a single oral dose of 100 mg losartan as a test or reference formulation. The plasma concentrations of losartan and its active metabolite were analyzed by a rapid and sensitive HPLC method with UV detection. The pharmacokinetic parameters included AUC0-36h, AUC0-infinity, Cmax, t1/2, and Ke. Values of AUC0-infinity demonstrate nearly identical bioavailability of losartan from the examined formulations. The AUC0-infinity of losartan was 2019.92+/-1002.90 and 2028.58+/-837.45 ng x h/ml for the test and reference formulation, respectively. The AUC0-infinity of the metabolite was 10851.52+/-4438.66 and 11041.18 +/-5015.81 ng x h/ml for test and reference formulation, respectively. The maximum plasma concentration (Cmax) of losartan was 745.94+/-419.75 ng/ml for the test and 745.74+/-329.99 ng/ml for the reference product and the Cmax of the metabolite was 1805.77+/-765.39 and 1606.22 +/-977.22 ng/ml for the test and reference product, respectively. No statistical differences were observed for Cmax and the area under the plasma concentration-time curve for both losartan and its active metabolite. 90 % confidence limits calculated for Cmax and AUC from zero to infinity (AUC0-infinity) of losartan and its metabolite were included in the bioequivalence range (0.8-1.25 for AUC). This study shows that the test formulation is bioequivalent to the reference formulation for losartan and its main active metabolite.     

Motives and perception of healthy volunteers who participate in experiments

Summary Healthy volunteers who participated in an experiment were asked to complete a questionnaire about their experiences. Special attention was paid to their motives and the informed consent procedure.The motives of healthy volunteers for participating in a study differed according to age. Young volunteers mostly participated because of the financial compensation, while older volunteers mainly participated to get a medical check-up, which was part of the selection procedure, or because of the benefit that other people might obtain from the results of the experiment.In most experiments the volunteers were content with the information given about the experiment, which was provided orally and in a hand-out. The information procedure was crucial for the experiment, because optimum information was of the utmost importance in keeping the volunteers motivated during the experiment. Another conclusion was that the researcher should not be afraid that too much information was given. Adequate information was also important in recruiting new volunteers, because they mostly become interested because of information obtained from their predecessors.A personal approach towards the volunteers during the experiment was appreciated by them and was an important help in keeping the volunteers motivated during the experiment.     

液相色谱-串联质谱法同时测定人血浆中氯沙坦、5-羧酸氯沙坦和氢氯噻嗪的浓度及药动学

目的建立人血浆中氯沙坦钾及其活性代谢物5-羧酸氯沙坦(EXP-3174)和氢氯噻嗪浓度的液相色谱-串联质谱(LC-MS/MS)测定法,研究氯沙坦钾氢氯噻嗪片在健康人体内的药动学。方法 24名男性健康受试者单剂量空腹口服氯沙坦钾氢氯噻嗪片后48 h内间隔采集肘静脉血,分离血浆测定氯沙坦钾,EXP-3174和氢氯噻嗪血药浓度,采用DAS2.0软件计算药动学参数。结果氯沙坦钾、EXP-3174和氢氯噻嗪的主要药动学参数ρmax分别为(276±127)、(463±135)和(63.8±19.2)μg·L-1;tmax分别为(1.43±1.06)、(3.67±1.32)和(2.40±0.79)h;t1/2分别为(1.53±0.44)、(4.72±1.27)和(5.77±1.52)h;AUC0-48分别为(505±120)、(3 305±646)和(415±103)μg·h·L-1。结论建立的LC-MS/MS测定法专属准确、灵敏度高,可用于氯沙坦钾氢氯噻嗪片血药浓度分析及药动学研究。     

Purine-mediated signalling in pain and visceral perception

Receptor subtypes for purines have been identified in a variety of tissues, increasing interest in the roles of purine-mediated signalling in pathophysiological processes. Growing evidence supports the involvement of one of the purinoceptor subtypes, P2X3, in nociception. In this article, recent studies of purine-mediated nociception and visceral pain will be discussed. Furthermore, a novel hypothesis is proposed for purine-mediated mechanosensory transduction where ATP released during distension from epithelial cells lining tubes (such as ureter and gut) and sacs (such as the bladder) acts on P2X3 receptors on a subepithelial nerve plexus to initiate impulses that are relayed via the spinal cord to pain centres in the brain.