Effects of Aminooxyacetic Acid and Baclofen on the Catalepsy and on the Increase of Mesolimbic and Striatal Dopamine Turnover Induced by Haloperidol in Rats

Abstract Effects of aminooxyacetic acid (AOAA) and baclofen on the catalepsy and on the increase of mesolimbic and striatal dopamine turnover induced by haloperidol were studied in rats. AOAA (25 mg/kg intraperitoneally) which increases the cerebral concentration of δ–aminobutyric acid (GABA) and baclofen (10 mg/kg intraperitoneally), a structural analogue of GABA, did not induce catalepsy by themselves but potentiated the catalepsy caused by haloperidol (0.1 mg/kg subcutaneously). AOAA and baclofen did not alter the haloperidol–induced striatal homovanillic acid increase. AOAA and baclofen decelerated the dopamine disappearance caused by α–methyl–p–tyrosine (αMT) both in mesolimbic nuclei and striatum. Haloperidol accelerated the αMT–induced dopamine disappearance in these structures. AOAA and baclofen prevented this stimulatory effect of haloperidol on the dopamine turnover. These results support the earlier suggestions that GABAergic pathways have an inhibitory effect on the mesolimbic and striatal dopaminergic pathways.     

Study on Brain Interstitial Fluid Distribution and Blood-Brain Barrier Transport of Baclofen in Rats by Microdialysis

Purpose. This study was performed to examine the distribution in the brain interstitial fluid (ISF) and the blood-brain barrier (BBB) transport of baclofen in rats by a microdialysis technique. Methods. Following an i.v. bolus administration and/or the constant i.v. infusion of baclofen to the microdialysis cannula-bearing anesthetized rats, the concentrations of baclofen in the hippocampal ISF, whole brain tissue, cerebrospinal fluid (CSF), and plasma were determined by high-performance liquid chromatography (HPLC). Data were kinetically analyzed to estimate the transport parameters, i.e., the influx clearance (CL_in) from plasma to brain and the efflux rate constant (k_eff) from brain to plasma, and the steady-state volume of distribution in the brain (V_d). Results. The concentrations of baclofen in ISF, whole brain tissue, and CSF at the pseudo-steady state were almost 30-fold lower than the plasma unbound concentration, suggesting the restricted distribution of baclofen in the brain. The estimated values of CL_in and k_eff were 0.00157 ± 0.00076 ml/min/g of brain and 0.0872 ± 0.0252 min^–1, respectively. The efflux clearance (CL_out) calculated by multiplying k_eff by V_d (0.816 ± 0.559 ml/g of brain) was 0.0712 ± 0.0529 ml/min/g of brain, and it was significantly 40-fold greater than the CL_in value and fully greater than the convective flow in ISF. Furthermore, no significant concentration gradient was observed between ISF and CSF. These results suggest that the CL_out value mainly reflects the efflux clearance through the BBB. Additionally, the hippocampal ISF/plasma concentration ratio of baclofen was markedly increased by both systemic administration of probenecid and its direct instillation into ISF. Conclusions. The restricted distribution of baclofen in the brain ISF may be ascribed to the efficient efflux from the brain through the BBB which is regulated possibly by a probenecid-sensitive organic anion transport system.     

川芎嗪与阿魏酸配伍对大鼠心肌缺血再灌注损伤心肌的保护作用

目的:观察川芎嗪与阿魏酸配伍对大鼠心肌缺血再灌注损伤的保护作用。方法:将健康雄性SD大鼠64只,随机分为4组,每组16只。分别为正常组、假手术组、模型组及川芎嗪与阿魏酸配伍组。后2组制备大鼠急性心肌缺血再灌注损伤模型。造模6h后检测血清肌酸磷酸激酶(CK)、乳酸脱氢酶(LDH)、心肌超氧化物歧化酶(SOD)、丙二醛(MDA);24h后取心脏,RT-PCR法检测细胞间黏附分子(ICAM-1)、P-选择素、E-选择素mRNA表达。结果:川芎嗪与阿魏酸配伍可明显降低心肌缺血再灌注损伤大鼠血清CK(P<0.01);但对血清LDH以及心肌SOD和MDA作用不明显(P>0.05);还可显著降低E-选择素、P-选择素mRNA表达(P<0.01)。结论:川芎嗪与阿魏酸配伍对大鼠心肌缺血再灌注损伤心肌有明显的保护作用。     

北豆根不同组分大鼠长期毒性实验研究

目的观察连续给予北豆根不同组分导致大鼠慢性毒性的损伤表现、程度及可逆性。方法分别给140只大鼠灌胃高、中、低剂量的北豆根水提、醇提组分样品,除观察一般状况外,检测血常规、血生化指标,剖杀大鼠,精密称取心、肝、脾、肺、肾脏,计算脏、体比值,进行常规病理检查。停药后,进行恢复期观察。结果北豆根水提、醇提组分分别给药27天、33天可导致大鼠体重下降,饮食、饮水不佳,血清丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、碱性磷酸酶(ALP)活性升高。水提组分的肝体比值增大,醇提组分肝、肾体比值均增大;肝、肾毒性损伤程度与给药剂量呈现一定的剂量依赖相关性,经过恢复期观察,部分病变不可逆。结论北豆根不同组分对大鼠长期毒性表现主要是肝、肾损伤,尤其以醇提的损伤最大,且部分病变为不可逆性损伤。     

α-硫辛酸抗心肌肥厚作用

目的研究α 硫辛酸（α LA）抗异丙肾上腺素致大鼠心肌肥厚的作用。方法24只大鼠随机分为模型组、对照组、硫辛酸组,每组8只。模型组和硫辛酸组建立心肌肥厚模型,硫辛酸组同时给予α 硫辛酸盐液腹腔注射,100 mg&#8226;kg－1&#8226;d－1,qd。测定大鼠全心质量指数（HW/BW）、左心室质量指数（LVW /BW,即LVI）,放射免疫分析法和逆转录聚合酶链反应（RT PCR）检测大鼠心肌组织血管紧张肽Ⅱ（AngⅡ）、AT1R含量及AT1mRNA表达水平,硫代巴比妥酸法测定丙二醛（MDA）含量,黄嘌呤氧化酶法测定超氧化物歧化酶（SOD）活性。结果与对照组比较,模型组大鼠HW/BW、LVI明显升高,心肌AngⅡ、AT1R含量及AT1mRNA表达水平增高,心肌和血清MDA含量增高,SOD含量降低（P＜0.01）;与模型组比较,硫辛酸组各心脏指标均明显减低,心肌组织MDA、AngⅡ、AT1R含量及AT1mRNA表达水平降低,SOD含量增高（P＜0.01）。结论氧化应激参与心肌肥厚的发生发展,α LA通过抗氧化作用抑制心肌肥厚的发生发展。     

香加皮不同组分大鼠长期毒性研究

目的 观察连续给予香加皮不同组分导致大鼠慢性毒性的损伤表现、程度及可逆性.方法 分别给140只大鼠灌胃高、中、低剂量的香加皮水提组分和醇提组分样品,除观察一般状况外,检测血常规、血生化指标,剖杀大鼠,精密称取心、肝、脾、肺、肾脏等重要脏器,计算脏、体比值,进行常规病理检查.停药后,进行恢复期观察.结果 连续20天给予不同剂量的香加皮水提组分和连续9天给予不同剂量的醇提组分样品均可导致大鼠体重下降,饮食、饮水不佳,血ALT、AST、AKP、TPC增高,ALB、CR降低、A/G比值降低,肝脏重量和肝体比值、肾脏重量和肾体比值增大,病理检查可见不同程度的肝脏、肾脏病理组织损伤;对血常规影响不明显;肝、肾毒性损伤程度与给药剂量呈现一定的剂量依赖相关性;经过恢复期观察,上述部分病变不可逆.结论 香加皮水提组分给药20天、醇提组分给药9天造成的慢性毒性损伤部位以肝、肾损伤为主,且部分病变为不可逆性损伤.     

氯沙坦联合小剂量叶酸对自发性高血压大鼠血液流变学和血管结构的影响

追踪在新药研发的一线关注于药学应用的前沿《中国现代应用药学》创刊于1984年,是由中国药学会主办,中国科协主管,国内外公开发行的     

Central Cardiovascular Effects of Gamma-Hydroxybutyric Acid: Interactions with Noradrenaline,Serotonin, Dopamine and Acetylcholine Transmission

Abstract: Gamma-hydroxybutyric acid (GHBA) increased arterial blood pressure and heart rate dosedependently following intraperitoneal and intracerebroventricular administration to conscious rats. Cardiovascular responses to GHBA were completely prevented after pretreatment with reserpine or phenoxybenzamine and after a prehypothalamic brain transection. Intraperitoneal GHBA increased brain noradrenaline (NA) synthesis and utilization, particularly in the neocortex. Selective central NA depletion in combination with NA synthesis inhibition prevented the cardiovascular effects of GHBA. No overt interactions were observed with agents influencing 5-hydroxytryptamine (5-HT), dopamine (DA), or acetylcholine (Ach) transmission. Pentobarbitone but not diazepam or diphenylhydantoin abolished the hypertensive properties of GHBA. We conclude that the cardiovascular effects of GHBA are of central origin and that they are mediated via the peripheral sympathetic nervous system. They are dependent on an intact central NA transmission while there are few indications for a significant role of central DA-, 5-HT or Ach-mechanisms.     

艾叶不同组分对正常大鼠长期毒性实验研究

目的观察连续给予艾叶不同组分导致大鼠慢性毒性的损伤表现、程度及可逆性。方法连续21天分别给140只大鼠灌胃高、中、低剂量的艾叶水提组分和挥发油组分样品,除观察一般状况外,检测血常规、血生化指标,剖杀大鼠,精密称取心、肝、脾、肺、肾脏等重要脏器,计算脏、体比值,进行常规病理检查。停药后,继续20天恢复期观察。结果连续21天给予不同剂量的艾叶水提组分和挥发油组分样品均可导致大鼠体重下降,饮食、饮水不佳,血ALT、AST、AKP、TPC增高,ALB降低、A/G比值降低,肝脏重量和肝体比值增大,病理检查可见不同程度的肝脏病理组织损伤;对血常规、肾功能的影响不明显;肝毒性损伤程度与给药剂量呈现一定的剂量依赖相关性;经过20天恢复期观察,上述部分病变不可逆。结论艾叶水提、挥发油组分对大鼠给药21天导致的长期毒性表现主要是肝损伤,尤其以挥发油的损伤最大,且部分病变为不可逆性损伤。     

Effect of muscimol,a central GABA receptor agonist,on the catalepsy,striatal homovanillic acid increase,and analgesia induced by pilocarpine in rats

Muscimol, a structural analog of GABA, significantly potentiated pilocarpine-induced analgesia in rats, but failed to alter pilocarpine-induced catalepsy. It also failed to affect pilocarpine-elicited increase in homovanillic acid levels in the striatum. These findings suggest that the potentiation of pilocarpine-induced analgesia by muscimol is unrelated to an interaction of the GABAergic system with the striatal cholinergic or dopaminergic systems.     

丹酚酸B对大鼠离体心脏缺血再灌注损伤的保护作用

目的：研究丹酚酸B对大鼠离体心脏缺血再灌注损伤的保护作用。方法：大鼠离体心脏采用Langendorff装置,灌注含氧K．H液30min后,夹闭,停止灌流30min,然后再灌注40min。实验分为模型（空白K_H液）组、葛根素（0．24mmol／1）组与丹酚酸B高、中、低浓度（60、30、15gmol／1）组。灌注含氧K．H液20min后加入相应药物灌注10min。实时测定血流动力学指标、左室舒张末期压（LVEDP）、左室发展压（LVDP）、左室收缩压最大变化速率（＋dP/dtmax）、左室舒张压最大下降速率（-dP／dtmax）。收集灌流液,并测定肌酸激酶（CK）的活力;取部分心肌组织测定丙二醛（MDA）含量与超氧化物歧化酶（sou）活性。结果：与模型组比较,丹酚酸B高、中浓度组大鼠离体心脏在复灌10min后L、厂EDP显著降低,LVDP显著升高,＋dP/dtmax。显著升高,-dP／dtmax显著降低（P〈0．01或P〈0．05）;丹酚酸B高浓度组离体大鼠心脏组织CK活性显著减弱（尸〈O．01）,丹酚酸B高、中浓度组大鼠离体心脏MDA含量显著减少,SOD活性显著增强（P〈0．01）;丹酚酸B高、中、低浓度组大鼠离体心脏复灌5min后灌流液显著增加（P〈O．01或P〈0．05）。结论：丹酚酸B对大鼠离体心脏有保护作用,其机制可能是通过清除氧自由基,抵抗氧化应激发挥治疗作用。     

黄芪总黄酮提取物对维甲酸所致大鼠骨质疏松的影响

目的:研究黄芪总黄酮提取物对维甲酸造成的大鼠骨质疏松状态的改善作用.方法:大鼠口服维甲酸80 mg·kg-1·d-1,连续2周后造成骨质疏松模型,观察黄芪总黄酮提取物的药理作用.结果:与维甲酸模型组比较,黄芪总黄酮提取物的中、高剂量组能显著提高骨质疏松模型大鼠的骨密度,并且对大鼠的骨长度指数、体重及生殖器官脏器指数也有一定的影响.结论:一定剂量的黄芪总黄酮提取物有明显的改善骨质,增加骨密度、防治生殖器官损伤的作用.     

Effects of Gender,Pregnancy, and Anesthesia on the Pharmacokinetics of Zidovudine in Rats

Purpose. The effects of gender, pregnancy and anesthesia on the pharmacokinetics of zidovudine (AZT) were studied in rats. Methods. Unanesthetized male (MR), female (FR) and pregnant (day 20, PR) rats received 50 mg/kg AZT via a jugular vein cannula. Female (FRA), pregnant (day 20, PRA) and pregnant (day 20, PRR) rats maintained under ketamine: acepromazine:xylazine anesthesia also received 50 mg/kg AZT. Two fetuses were removed at each sampling time from the PRR group. Plasma samples were collected and analyzed by RIA. Results. With the exception of a lower non-renal clearance in female rats, there were no gender differences in the disposition of AZT. No significant differences were noted in total clearance, non-renal clearance or volume of distribution between pregnant and female rats, however, significant differences in renal clearance values were evident. Anesthesia resulted in decreased total, renal and non-renal clearances in female and pregnant rats. The removal of fetuses during the experiments did not alter the total clearance of AZT in pregnant rats, however, renal clearance and volume of distribution were decreased by cesarian section. Conclusions. The rat appears to be a suitable laboratory animal model for investigating AZT disposition during pregnancy. However, results of pharmacokinetic studies when animals are maintained under anesthesia with ketamine :acepromazine:xylazine must be interpreted with caution.     

Antidepressant Effects of Abscisic Acid Mediated by the Downregulation of Corticotrophin-Releasing Hormone Gene Expression in Rats

Background:

Corticotrophin-releasing hormone (CRH) is considered to be the central driving force of the hypothalamic-pituitary-adrenal axis, which plays a key role in the stress response and depression. Clinical reports have suggested that excess retinoic acid (RA) is associated with depression. Abscisic acid (ABA) and RA are direct derivatives of carotenoids and share a similar molecular structure. Here, we proposed that ABA also plays a role in the regulation of CRH activity sharing with the RA signaling pathway.

Methods:

[₃H]-ABA radioimmunoassay demonstrated that the hypothalamus of rats shows the highest concentration of ABA compared with the cortex and the hippocampus under basal conditions.

Results:

Under acute stress, ABA concentrations increased in the serum, but decreased in the hypothalamus and were accompanied by increased corticosterone in the serum and c-fos expression in the hypothalamus. Moreover, chronic ABA administration increased sucrose intake and decreased the mRNA expression of CRH and retinoic acid receptor alpha (RARα) in the hypothalamus of rats. Furthermore, ABA improved the symptom of chronic unpredictable mild stress in model rats, as indicated by increased sucrose intake, increased swimming in the forced swim test, and reduced mRNA expression of CRH and RARα in the rat hypothalamus. In vitro, CRH expression decreased after ABA treatment across different neural cells. In BE(2)-C cells, ABA inhibited a series of retinoid receptor expression, including RARα, a receptor that could facilitate CRH expression directly.

Conclusions:

These results suggest that ABA may play a role in the pathogenesis of depression by downregulating CRH mRNA expression shared with the RA signaling pathway.     

复方熊去氧胆酸口服液对大鼠肝纤维化的防治作用

目的：观察复方熊去氧胆酸口服液（C-UDCA）对四氯化碳（CCl4）致大鼠肝纤维化的防治作用。方法：采用皮下注射40%CCl4-花生油溶液制备肝纤维化模型,检测经口给予C-UDCA后对大鼠肝功能指标、肝纤维化各项生化指标及肝组织病理形态学的影响。结果：C-UDCA各剂量组能显著减轻CCl4导致的肝脂肪变性、肝细胞损伤和纤维组织增生。与UDCA相比,C-UDCA-H能显著降低血清ALT、AST、HA、PCⅢ、CⅣ、LN及肝组织Hyp含量,显著升高血清Alb、A/G、肝组织GSH含量;C-UDCA-M亦能显著降低血清HA、LN 含量。结论：C-UDCA对CCl4致大鼠肝纤维化具有一定的防治作用,且C-UDCA-H、C-UDCA-M的作用优于UDCA。     

雾化吸入柠檬酸对贫铀致大鼠肺成纤维细胞增生的影响

目的:探讨雾化吸入柠檬酸对贫铀(DU)致大鼠肺成纤维细胞增生的影响及其机制。方法:取大鼠随机分为生理盐水组、模型组和柠檬酸组,后2组灌肺给予贫铀建模。柠檬酸组建模30min后雾化吸入20%柠檬酸,流量为1.44mL.min-1,每日1次,每次20min,连续给药7d。采用湿消化法检测各组大鼠建模给药后第7、15、30天(n=13)时肺铀含量,观察肺组织病理学变化及肺间质胶原沉积情况,免疫组化法检测肺泡区基质金属蛋白酶9(MMP-9)及其组织金属蛋白酶抑制物1(TIMP-1)表达情况。结果:与生理盐水组比较,模型组大鼠肺铀含量和MMP-9、TIMP-1表达均明显增加(P<0.05),且随时间延长肺铀含量逐渐降低;与模型组同时间点比较,柠檬酸组3个时间点肺铀含量和15、30d时MMP-9、TIMP-1表达均明显降低(P<0.05或P<0.01),且柠檬酸组15、30d时MMP-9、TIMP-1表达与生理盐水组比较无明显差异(P>0.05);模型组大鼠15、30d时肺成纤维细胞明显增生、肺间质胶原沉积明显,与其相同时间点比较,柠檬酸组15、30d时增生、沉积均减轻。结论:雾化吸入柠檬酸对贫铀致大鼠肺损伤具有保护作用,其可能机制是降低成纤维细胞增生。     

阿魏酸长期给药后对大鼠灌服氯沙坦钾的药动学影响

目的 研究长期给药阿魏酸对大鼠体内氯沙坦及其代谢物E-3174的药动学影响。方法 12只健康♂ SD大鼠随机分成2组（每组6只）,试验组每天灌胃50 mg·kg^-1阿魏酸,连续诱导7 d;对照组灌胃等体积0.5%CMC-Na。第8天给药30 min后,给予氯沙坦钾（5 mg·kg^-1）。分别于给药前和给药后0.25,0.5,0.75,1,1.5,2,3,4,6,8,10,12,24 h大鼠尾静脉取血,血样处理后采用UPLC-MS/MS检测大鼠血浆中氯沙坦及E-3174的浓度。结果 虽然2组大鼠体内氯沙坦各项药动学参数对比均无统计学意义,但是试验组大鼠体内E-3174的AUC（0-t）、AUC（0-∞）和Cmax显著增高（P<0.05）;CL/F、Tmax显著降低（P<0.05）。结论 大鼠长期给药阿魏酸后虽然未能引起氯沙坦原形药物药动学的变化,但可使其活性代谢产物E-3174代谢减慢,浓度增高,药时曲线下面积增大。     

新癀片及其中药组分对次黄嘌呤致高尿酸小鼠的影响

目的探讨新癀片及其中药组分对次黄嘌呤所致的高尿酸小鼠的影响,并初步探讨其机制。方法采用腹腔注射次黄嘌呤引起的高尿酸小鼠动物模型和正常小鼠,分别以新癀片及其中药组分不同剂量组进行灌胃,给药结束后测定血尿酸水平以及肝脏中黄嘌呤氧化酶活性。结果腹腔注射次黄嘌呤1h后,阳性组、新癀片低中高剂量组(23.75、47.5、95mg·kg-1)、新癀片中药组分低中高剂量组(23.75、47.5、95mg·kg-1),能明显对抗次黄嘌呤引起的高尿酸作用(P<0.01),且对肝脏中黄嘌呤氧化酶的活性有一定程度的抑制作用。结论新癀片及其中药组分可能通过抑制黄嘌呤氧化酶的活性来降低血尿酸水平。