首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 390 毫秒
1.
采用单次灌胃染毒法,通过高效液相色谱仪测定,研究了苯肽胺酸(N-phenylphthalamicacid,PPA)在大鼠体内的吸收、组织分布及排泄情况,以及其血药浓度经时变化过程和毒物动力学参数。结果表明:苯肽胺酸经消化道吸收速率较快,其半吸收期t1/2ka仅为(0.15±0.11) h,血药浓度的达峰时间(tmax)为(0.68±0.37) h,血药峰浓度(Cmax)值为(141.48±27.87) mg/L;苯肽胺酸在大鼠体内分布快且分布范围广,半分布期(t1/2α)为(0.22±0.18) h,表观分布容积(Vz/F)为(17.54±7.71) L/kg;苯肽胺酸从大鼠体内消除较快,其清除率(CLz/F)为(1.32±0.51) (L/h)/kg,在体内平均驻留时间(MRT(0-∞))为(25.69±2.93) h,消除半减期(t1/2z)为(7.77±1.44) h,约35 h后95%以上的苯肽胺酸可从大鼠体内消除。研究发现:苯肽胺酸的浓度-时间曲线呈现双峰现象,提示其在大鼠体内可能存在肠-肝循环。从大鼠灌胃染毒后至24 h内,被测各组织、脏器中均可检出苯肽胺酸,其浓度由高到低依次为:肾脏> 肺> 肝脏> 心脏> 脾脏> 肌肉> 睾丸> 脂肪> 大脑,肾脏中药物含量达192.7 μg/g,同时仅肾脏组织的靶向分布系数(te)值大于1(4.77),提示苯肽胺酸在大鼠体内分布时对肾脏具有相对较高的选择性。排泄物研究结果显示,苯肽胺酸随粪便排出的总量仅占给药量的1.45%,而尿液中未检出苯肽胺酸。  相似文献   

2.
2-溴-4-氟乙酰苯胺 (2-bromo-4-fluoroacetanilide,BFAA) 是多种N-苯基酰胺类化合物合成的中间体,也是合成农药时的主要杂质。本研究建立了一种快速、特异的超高效液相色谱-串联质谱 (UPLC-MS/MS) 检测方法,用于测定大鼠血浆、组织、尿液和粪便中的2-溴-4-氟乙酰苯胺含量,以获得该化合物的吸收、分布及排泄等动力学信息。大鼠经不同剂量的2-溴-4-氟乙酰苯胺灌胃和静脉注射染毒处理后,取血浆及不同组织样品,经蛋白质沉淀法处理后采用所建立的UPLC-MS/MS方法测定,分别计算2-溴-4-氟乙酰苯胺的血药浓度达峰时间 (tmax)、血药峰浓度 (Cmax) 和药-时曲线下面积 (AUC(0-t)) 等血浆毒物动力学参数和绝对生物利用度 (F),考察了药物在组织中的分布和经尿液、粪便排泄的特征。血浆毒物动力学研究表明:大鼠灌胃后药物可被迅速吸收,给予200、500和1000 mg/kg的2-溴-4-氟乙酰苯胺后,其 tmax 值分别为 (0.2 ± 0.1)、(0.4 ± 0.2) 和 (0.5 ± 0.3) h;Cmax 和 AUC(0-t) 值分别为 (32.4±5.0)、(45.2±1.8)、(38.5±3.2) mg/L和(121.2±40.9)、(393.3±51.1)、(321.9±38.0) (mg/L)·h;F 值在 34.1%~83.3% 之间。其血浆药-时曲线具有双峰现象,推测可能存在重吸收或肠-肝循环。组织分布研究表明:2-溴-4-氟乙酰苯胺在组织中分布较广,且主要分布在小肠、胃和脂肪中;此外在脑和睾丸中发现了少量该化合物,表明其可以穿过血脑屏障和睾丸屏障;24 h后大部分组织中已检测不到该化合物,表明其总体不存在蓄积现象;靶向分配系数均小于1.0,提示2-溴-4-氟乙酰苯胺对组织无明显的选择性。排泄研究结果表明:2-溴-4-氟乙酰苯胺经尿液和粪便的排泄主要发生在0~48 h内,分别占总排泄量的93%和92%;经尿液和粪便的总排泄量为 (80.6 ± 29.8) μg,仅占总染毒量的 (0.03 ± 0.01) %,提示经尿液和粪便的排泄并非2-溴-4-氟乙酰苯胺母体化合物主要的体内消除途径。  相似文献   

3.
螺虫乙酯在染毒雄性大鼠体内的分布与代谢   总被引:2,自引:2,他引:0  
建立了采用超高效液相色谱-串联质谱仪(UPLC-MS/MS)检测不同动物样品中螺虫乙酯及其主要代谢物残留量的方法,并研究了螺虫乙酯在大鼠体内的吸收与代谢。样品中螺虫乙酯及其主要代谢物经甲醇提取及C18固相萃取(SPE)柱净化后,用UPLC-MS/MS检测。结果显示,所建立方法快速、灵敏,每个样品上机检测仅需3 min,方法的最低检出浓度(LOQ)为0.005 mg/kg。对按照每千克体重每日250 mg剂量染毒28 d后的大鼠体内螺虫乙酯残留量的检测结果表明:螺 虫乙酯在睾丸、肝脏、肺、肾、心脏、血浆等器官和组织中的残留量较低,平均在0.012~0.025 mg/kg 之间,且分布差异不显著,而脂肪和肌肉中螺虫乙酯的残留量显著低于睾丸和肝脏中的残留量(P P 肾>血浆>肺>心脏>睾丸>脂肪>肌肉。  相似文献   

4.
建立了大鼠组织中氟噻草胺的液相色谱-串联质谱 (LC-MS/MS) 分析方法,并对其经灌胃给药后在大鼠体内各组织中的分布行为进行了研究。大鼠组织样品经乙腈提取后,采用LC-MS/MS法测定。色谱柱为Phenomenex反向C18色谱柱 (50 mm × 4.6 mm,5 μm),以体积分数为72%乙腈水溶液 (含体积分数为0.1%甲酸) 为流动相,等度洗脱,流速0.6 mL/min。质谱采用电喷雾离子源 (ESI) 及多重反应监测 (MRM) 模式,定量离子对为m/z 364.1/194.2。大鼠心、肝、脾、肺、肾、脑、肌肉、睾丸和脂肪在0.002~0.1 mg/L范围内,大肠、小肠和胃在0.10~10 mg/L范围内,氟噻草胺的质量浓度与对应的峰面积间线性关系良好 (r > 0.99)。质控样品的相对标准偏差均小于11%,基质效应在94.5%~95.6%之间,提取回收率在96%~107%之间,稳定性在95%~104%之间,均符合方法学要求。经单次灌胃给予氟噻草胺400 mg/kg后,其主要分布于大鼠的胃、大肠、小肠和肺中,各组织浓度达峰值后,随着时间延长均可从体内消除。表明氟噻草胺在动物体内分布广泛且降解迅速。本研究建立了一种可用于测定大鼠组织中氟噻草胺浓度的高效、专属、灵敏的LC-MS/MS方法,进而阐明了氟噻草胺的组织分布行为。  相似文献   

5.
环氧虫啶对灰飞虱种群增长和拟水狼蛛捕食功能的影响   总被引:1,自引:0,他引:1  
以哌虫啶和吡蚜酮为参照药剂, 评价了环氧虫啶对灰飞虱若虫的毒性, 及其在亚致死剂量下对灰飞虱种群增长的影响; 同时测定了环氧虫啶在对灰飞虱若虫LC90剂量下喷雾处理后, 拟水狼蛛对灰飞虱的捕食功能反应变化。结果表明:环氧虫啶对灰飞虱若虫的毒力依次大于哌虫啶和吡蚜酮。3种杀虫剂在亚致死剂量下对灰飞虱种群增长都有不同程度的抑制作用, 其中环氧虫啶的抑制作用最大, 表现在处理后的种群趋势指数和相对适合度等参数均极显著低于对照。捕食功能试验表明, 3种药剂处理后拟水狼蛛对灰飞虱的捕食仍符合Holling Ⅱ模型, 但出现了猎物的处置时间延长、捕食速率和寻找效应下降, 其中环氧虫啶对拟水狼蛛捕食功能的负面影响小于吡蚜酮和哌虫啶。  相似文献   

6.
糙米和稻壳中哌虫啶的液相色谱残留分析有法   总被引:1,自引:0,他引:1  
研究并建立了哌虫啶在糙米和稻壳中的残留分析方法。样品经乙腈提取,C18固相萃取小柱净化后,液相色谱检测(SPE—LC)。样品前处理过程简单,方法准确可靠,灵敏度和准确度达到了农药残留检测的要求。哌虫啶标准曲线的线性范围为0.1-10mg/L,线性相关系数为0.9993,哌虫啶在上述样品(添加0.02、2mg/kg)中的添加回收率在78.0%-99.1%之间,变异系数最大为8.64%。  相似文献   

7.
采用乙腈提取、固相萃取净化和高效液相色谱法,分析测定了啶虫脒在露地和大棚2种种植条件下黄瓜和土壤中的残留及消解动态。结果表明:9%啶虫脒可湿性粉剂同时在露地和大棚中按有效成分30.375 g/hm2剂量(推荐高剂量的1.5倍)施药1次,啶虫脒在露地和大棚黄瓜及其土壤中的原始沉积量分别为0.20、0.13 mg/kg和0.29、0.14 mg/kg,露地黄瓜和土壤中的原始沉积量均分别低于大棚;相应地,啶虫脒在黄瓜和土壤中的半衰期分别为9.7、9.4 d(露地)和10.1、11.9 d(大棚)。9%啶虫脒可湿性粉剂同时在露地和大棚中按有效成分20.25 g/hm2和30.375 g/hm2的剂量施药1次和2次,在相同施药剂量、施药次数和采收间隔期情况下,除个别情况外,露地黄瓜中啶虫脒的最终残留量均低于大棚,分别为0.01~0.05 mg/kg(露地)和0.01~0.09 mg/kg(大棚)。  相似文献   

8.
利用生理毒物代谢动力学(PBTK)模型,对大鼠经口摄入敌敌畏后其在体内分布及转化代谢过程进行模拟,旨在探寻评价敌敌畏饮食暴露风险的合理方法。该PBTK模型共包括4个房室:肝脏、肾脏、充分灌注室和不充分灌注室,各房室内敌敌畏的浓度变化率采用质量守恒微分方程表示。根据欧拉数值计算方法,对大鼠经口摄入敌敌畏后的毒物代谢动力学数据进行模拟,分别预测了大鼠经口摄入10、25和50 mg/kg b.w.的敌敌畏后,肝脏和血液中敌敌畏浓度变化以及血液中乙酰胆碱酯酶活性变化的曲线。为验证该方法的准确性,将大鼠经口摄入35 mg/kg b.w.敌敌畏后血液中敌敌畏的浓度变化模拟值,以及经口摄入10 mg/kg b.w.敌敌畏后血液中乙酰胆碱酯酶活性变化的模拟值与文献的实验测量值进行了比较,结果显示,模拟值与实验值之间不存在显著性差异。因此认为,利用该PBTK模型可以估测大鼠经口摄入敌敌畏后的体内生理毒物代谢动力学数据,为评估人体的有害物质暴露内剂量数据提供了便捷途径。  相似文献   

9.
采用工蚁与浸药滤纸接触或取食含药松木粉的方法,测定了啶虫脒、氰戊菊酯和硼酸,在亚致死剂量下对黄胸散白蚁Reticulitermes flaviceps工蚁体内内切-β-1,4-葡聚糖酶(EG)和β-葡糖苷酶(BG)活性的影响。结果表明,用0.5、1.0和2.0 mg/L的啶虫脒处理黄胸散白蚁工蚁6~48 h,对其体内的EG和BG酶活性(处理48 h的除外)无显著影响;用0.5、1.0和2.0 mg/L的氰戊菊酯处理,可显著降低黄胸散白蚁工蚁体内的EG和BG酶活性;硼酸对黄胸散白蚁工蚁体内EG和BG酶活性的影响与处理浓度和处理时间有关。  相似文献   

10.
为明确10%烯啶虫胺SL、25%环氧虫啶WP等药剂对稻飞虱的防效,2015年在邕宁区中和乡对稻飞虱进行了2种低毒药剂的药效试验。试验结果表明:10%烯啶虫胺SL 200 g/ha和25%环氧虫啶WP 360 g/ha,兑水750 kg/ha均匀喷雾皆对稻飞虱有理想的防效,且对水稻安全,可用于防治稻飞虱。  相似文献   

11.
Pyribenzoxim, benzophenone O‐[2,6‐bis(4,6‐dimethoxypyrimidin‐2‐yloxy)benzoyl]oxime, is a new post‐emergence herbicide providing broad‐spectrum weed control in rice fields. [14C]Pyribenzoxim was used to study the pharmacokinetics of the compound after oral administration of a dose of 1000 mg kg?1 to male Sprague–Dawley rats. The material balance ranged from 97.3 to 99.7% of the administered dose and urinary and fecal recovery accounted for 97.1%, with the majority of radioactivity recovered in feces (88.6%) by 168 h after treatment. Elimination as volatile products or as carbon dioxide was negligible. The following values were obtained for the compound in the blood: AUC0–168h, 28400 µg equiv h g?1; Tmax, 12 h; Cmax, 372 µg equiv g?1; half‐life, 53 h. Radioactivity in tissue decreased from 96.1% of applied radiocarbon at 6 h to 0.4% at 168 h and the highest concentration of radioactivity among the tissues was observed in liver while the lowest residues were found in brain. The elimination half‐lives of radioactivity from tissues was in the range of 7 to 77 h and Tmax values of 12, 24 and 12 h were observed for blood, liver and kidney, respectively. Except for that in the digestive tract, the tissue‐to‐blood ratio (TBR) was highest in the liver. © 2001 Society of Chemical Industry  相似文献   

12.
The tissue distribution and excretion of 14C-labeled propham and chlorpropham were investigated in the adult female rat after a single oral dosage. The average 3-day urinary excretions of radioactivity were 55.9%, 82.6%, 79.5%, and 85.4% of an oral dose of chain [14C] chlorpropham, ring [14C] chlorpropham, chain [14C] propham, and ring [14C] propham, respectively. With chain [14C] chlorpropham 35.4 ± 7.5% of the administered radioactivity appeared in the respired air, whereas only 5.0 ± 0.8% was found in CO2 from chain [14C] propham. There was no significant difference in the rate of excretion or the route of elimination among rats receiving different oral dosages, ranging from less than 4 mg/kg to 200 mg/kg. The radioactivity was distributed in all tissues with highest concentration found in the kidney. The average biological half-life of 14C from chlorpropham and propham in most organs was short, ranging between 3 and 8 hr; however, in brain, fat, and muscle, the half-life was about twice the value for other organs.Both compounds were metabolized by hydrolytic and oxidative mechanisms and the resulting metabolites were excreted either as free forms or as conjugates.Subcellular distribution of 14C in the rat liver and kidney after an oral administration of chlorpropham and propham was investigated. The percentage distribution of 14C in the particulate and soluble fractions was dependent on the elapsed time after dosing.  相似文献   

13.
[14C]Endosulfan, α or β isomers separately, was administered to rats as a single oral dose and as a dietary supplement for 14 days. No appreciable differences were observed in the fate of the two isomers. Five days after the single dose, 75% of the dose had been voided in the feces and 13% in the urine. Of the total radiocarbon consumed in the diet after 14 days, 56% had been eliminated in the feces and 8% in the urine. Bile collection studies showed that up to 47% of a single oral dose was eliminated from the liver via this route; enterohepatic circulation was not apparent. Maximum [14C]endosulfan equivalents in body tissue occurred in the kidney and liver, 3 and 1 ppm, respectively, after 14 days of feeding 5 ppm of endosulfan. Apolar metabolites in the excreta and/or tissues were a minor portion of the total residues and consisted of the sulfate, diol, α-hydroxy ether, lactone, and ether derivatives of endosulfan. The sulfate was slightly more toxic to mice than endosulfan, while the other products were less toxic. Neither endosulfan nor its metabolites were active in the Salmonella mutagenicity test. Endosulfan in the diet of rats for 28 days at 50 ppm did not induce liver oxidase enzymes, alter liver or kidney weights, or influence the rate of weight gain of the animals.  相似文献   

14.
为明确氯吡脲对大鼠的毒性作用,采用150、300和600 mg/kg剂量分别向SD大鼠灌胃 (ig) 给予氯吡脲,每日1次,连续给药4周。每日观察大鼠的中毒状况和死亡情况,每周记录体质量和摄食量;于停药后第1天和第15天分别处死SD大鼠,检测血常规、血清生化和凝血功能;取主要脏器进行称量,计算其脏器系数并进行常规病理组织学检查。结果发现:连续给药4周,氯吡脲对大鼠体质量、摄食量、血常规和凝血均无明显影响。停药后第1天,与溶剂对照组比较,氯吡脲300 mg/kg及以上剂量处理组雄性大鼠的尿素氮和肌酐含量明显升高 (P < 0.05),600 mg/kg剂量组血糖显著升高 (P < 0.05),其中,600 mg/kg处理组雄性大鼠的尿素氮、肌酐和血糖分别是对照的1.9、1.6和1.3倍。氯吡脲300 mg/kg及以上剂量组雌、雄性大鼠的肾脏系数均明显升高 (P < 0.05),其中300 mg/kg剂量组雌、雄性大鼠的肾脏系数分别是对照的1.2和1.1倍,600 mg/kg剂量组雌、雄性大鼠的肾脏系数分别是对照的1.4和1.1倍;300 和600 mg/kg剂量组雌性大鼠的肝脏系数明显升高 (P < 0.01),分别是对照的1.3和1.9倍。病理切片检查可见肾脏病理组织学改变,主要表现为轻度肾管萎缩,明显的白细胞管型、透明管型、间质炎性细胞浸润及肾小管扩张。停药后第15天,上述毒性反应症状有所恢复。研究表明,SD大鼠经连续灌胃给予氯吡脲4周,在600 mg/kg剂量下表现为明显肾脏毒性反应,在300 mg/kg剂量下表现为较轻微的肾脏毒性反应,推测氯吡脲的主要毒性靶器官可能是肾脏;其未见明显毒性反应剂量为150 mg/kg。  相似文献   

15.
The tissue distribution and excretion of [14CH3S]methamidophos was followed in female Sprague-Dawley rats after intravenous injection at a toxic, but nonlethal, dose (8 mg/kg). Radiolabel was rapidly distributed to all tissues at approximately equal concentrations. Peak tissue levels were achieved within 1–10 min except in the central and peripheral nervous system where peak levels (40 nmol/g) were found between 20 and 60 min, corresponding to peak signs of toxicity. Within 24 hr of dosing, 47% of the radioactivity was recovered in the urine and 34% as 14CO2 with <5% in the feces over 7 days. Cholinesterase (ChE) inhibition was measured in erythrocytes, plasma, and various regions of the central nervous system (CNS) at selected times after administration of methamidophos at 8 mg/kg. The degree of acetylcholinesterase (AChE) inhibition in the three CNS regions was similar, reaching a minimum of 15–20% of control values at 30–60 min, when toxicity was most severe. The degree of erythrocyte AChE inhibition was less than that of the CNS although the time course was similar. Plasma ChE inhibition was more rapid than that of the CNS or erythrocytes and reactivation was slower. When similar concentrations of methamidophos to those found in vivo were incubated with CNS homogenates, plasma, or erythrocytes in vitro (5 × 10?5M) a similar degree of inhibition occurred over the same time course. It is, therefore, concluded that the cholinergic toxicity produced by methamidophos is a result of the in vivo stability of this compound combined with its entry into the nervous system in sufficiently high concentrations to inhibit AChE.  相似文献   

16.
In controlled near-optimum conditions (18 °C), monocyclic sporulation capacity and spore infection efficiency were assessed for faba bean rust on the first and second leaves of field bean. After a latency period of 8–10 days, lesions sporulated duringc. 50 days. Spore production on the second leaf,c. 9×104 spores per lesion, was two times as high as spore production on the first leaf. Infection efficiency was similar for both leaf layers, with a mean value of 0.11 lesion per inoculated spore. Infection efficiency decreased strongly when spores originated from mother lesions older than 20 days. Three life-table statistics (the net reproduction numberR o , the mean generation timeT g , and the maximum relative growth rater max ) were calculated.R o was larger andT g was longer for the second than for the first leaf, butr max was nearly the same for both leaf layers (0.31–0.33 day–1).r max was compared with the exponential growth rater measured in a field experiment. From the difference between the two rates, the fraction of inoculum lost in field conditions was estimated at 0.54–0.94. The life-table statistics were also compared to those of other legume rusts, and implications of life-table analysis for comparative epidemiology were discussed.  相似文献   

17.
Oral administration of O,O,S-trimethyl phosphorothioate (OOS), an impurity in several technical organophosphorus insecticides, causes delayed toxicity in rats with death occurring up to 28 days after the treatment. The oral LD50 was determined to be 60 mg/kg. The effect of a single nonlethal dose of OOS (20 mg/kg) on in vivo protein synthesis in different organs was determined by measurement of the incorporation of [14C]leucine at 6 hr to 28 days after treatment. As early as 6 hr after OOS treatment the incorporation of [14C]leucine into the liver, lung, thymus, kidney, and spleen was elevated and remained elevated for up to 7 days. With the exception of the lung, organ weights were significantly decreased during the same time period. On Day 28 after treatment, the amount of [14C]leucine incorporation had decreased to the control level in all of the organs studied. Treatment with OOS at 20 mg/kg caused a significant increase in hematocrit on Days 3,5, and 7, and as early as 6 hr after treatment at 60 mg/kg. The clinical biochemistry of plasma indicated that there was no significant change from control values in the glutamic pyruvic transaminase, glutamic oxalic transaminase, lactate dehydrogenase, or alkaline phosphatase activities with the 20 mg/kg dose. The analysis of the intermediary metabolites indicated that the redox state of cytosol was more reduced on Day 5, whereas that of mitochondria was not affected by OOS. Data obtained at selected times after oral administration of a 60 mg/kg dose of OOS and that obtained from animals starved for 3 days are also discussed.  相似文献   

18.
Rats and chickens were each given a single oral dose (10 or 100 mg/kg body wt) of 1,1,1-trifluoro-N-[2-methyl-4-(phenylsulfonyl)phenyl-14C(U)]methanesulfonamide ([14C]perfluidone). Depending on the size of the dose, from 8.4 to 36.2% of the [14C] was eliminated in the urine and from 36.4 to 85.4% was eliminated in the feces within 48 hr after dosing. Less than 1% of the [14C] given to laying hens as [14C]perfluidone was present in the eggs produced during the first 96 hr after dosing. The percentage of the administered [14C] that remained in these animals (body with G.I. tract and contents removed) varied from 0.34 (96 hr after dosing) to 1.68% (48 hr after dosing). 14C-labeled compunds in the urine and feces from the rats and chickens were purified by solvent extraction, column chromatography, and gas-liquid chromatography, and then identified by infrared and mass spectrometry. The parent compound was the major 14C-labeled component in the urine and feces of both animals. 1,1,1-Trifluoro-N-[2-methyl-4-(3-hydroxyphenylsulfonyl)phenyl]methanesulfonamide was present in the feces of both animals. The proposed structures of other metabolites were 1,1,1-trifluoro-N-hydroxy-N-[2-methyl-4-(phenylsulfonyl)phenyl]methanesulfonamide (rat urine) and 1,1,1-trifluoro-N-{2-methyl-4-[(methylsulfonyl)-phenylsulfonyl]phenyl}methanesulfonamide (chicken urine).  相似文献   

19.
Abstract

The life history and fitness of Nilaparvata lugens being reared under ambient level (current CO2 concentration), medially elevated (550?µL/L) and highly elevated (750?µL/L) CO2 concentration for long-term generation were compared using two-sex life table instead of traditional age-specific life table. The results showed that significantly longer larval duration and lower fecundity of N. lugens were observed in 750?µL/L relative to 550?µL/L treatment (P?<?0.05). Accordingly, 550?µL/L CO2 significantly enhanced population parameters of N. lugens, including significantly higher intrinsic rate of increase (r), finite rate (λ) and net reproductive rate (RO), but not for 750?µL/L CO2. Taken together, N. lugens performs enhanced development rate, fecundity and survival in individual life history and higher potential in population multiplication under 550?µL/L CO2 level, while only indicates the less enhanced development rate and survival without significant increased capacity of population expansion under 750?µL/L CO2 level. These results should facilitate predicting the fitness and potential population damage of N. lugens, which is valuable for the integrated control of N. lugens in the future increasing CO2 concentration.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号