间硝苯啶、硝苯啶与尼群的平对动物降压作用的比较性研究

在清醒正常血压大鼠、免以及肾型高血压大鼠,比较了m-nif、nif及nitr的降压强度,和降压的时间动态过程,三药的降压作用与对照组及自身前后对比,统计学上均非常显著。m-nif与nitr降压持续时间较nif长。从清醒正常血压大鼠降压的量效关系比较,m-nif、nif和nitr的ED₅₀)分别为33.7±3.4,45.6±3.6和51.2±4.1 mg/kg(即90±9,132±10,142±11μmol/kg)。按克分子量计算对比m-nif的降压强度最大,nitr最弱。但三药对正常血压及肾型高血压动物的降压作用,按组间对比,无统计学差异。     

COMPARISON OF METHODS FOR ELICITING THE BARORECEPTOR-HEART RATE REFLEX IN CONSCIOUS RABBITS

1. Two methods were used for altering blood pressure in conscious rabbits by up to ± 30 mmHg from the resting level in order to characterize the barorecep-tor-heart rate reflex. These were to inflate descending aortic or inferior vena caval cuffs, or to give brief intravenous infusions of phenylephrine or glycerol trinitrate. The relation of change in blood pressure to change in heart interval was examined, both during the initial ‘ramp’ changes of these variables and when they had reached a ‘steady-state'. 2. Both methods allowed the construction of'steady-state’ sigmoid stimulus-response curves whose parameters were reproducible within animals, and which were attended by a relatively small variance between animals. The inflatable-cuff method gave a higher average value for maximum gain than the vasoactive drug method (10.0 v 5-4 ms/mmHg) and a narrower pressure range between the threshold and saturation points of the response, but values for the other parameters were similar. Corresponding parameters obtained by the two methods correlated closely. 3. After denervating all arterial baroreceptors except one carotid sinus, ‘steady-state’ maximum gain by cuff-inflation was reduced to 3.1 ms/mmHg, and to 2-6 ms/mmHg by the vasoactive drug method. The heart interval range between upper and lower plateau levels was reduced, but the pressure range between threshold and saturation points was widened, with both methods. 4. During the initial ‘ramp’ changes of blood pressure the sensitivity of the reflex was described by the slope of the linear regression of heart interval on ‘mean blood pressure. The slopes obtained by aortic cuff inflation, and by infusion of either vasoactive drug, correlated positively with ‘steady-state’ maximum gain. However, the reproducibility of the ‘ramp’ method was inferior to that of the ‘steady-state’ method with respect to reflex sensitivity, and other parameters of the stimulus-response relation cannot be estimated. 5. Complete baroreceptor denervation virtually eliminated heart rate changes over the range of blood pressures usually employed. However, when blood pressure was increased by more than 40 mmHg a profound reflex bradycardia and hypopnoea were then evoked.     

EVALUATION OF THE POTENTIAL IMMUNOTOXICITY OF BROMODICHLOROMETHANE IN RATS AND MICE

In the past two decades, concern has been expressed over the potential carcinogenicity of disinfection by-products (DBPs) found in chlorinated drinking water. More recently, research efforts have expanded to include noncancer endpoints as well. The objective of the present studies was to evaluate the potential of bromodichloromethane (BDCM), one of the most prevalent DBPs, to adversely affect immune function in mice and rats following drinking water or gavage exposure. Antigen-specific immunity was assessed as the antibody response to sheep erythrocytes; responses to T-and B-cell mitogens were evaluated as a non-antigen-specific measure of the proliferative potential of splenic and mesenteric lymph node lymphocytes. In consideration of an exposure route relevant to humans, C57BL/6 mice received 0.05, 0.25, or 0.5 g BDCM/L and F344 rats received 0.07 or 0.7 g BDCM/L via drinking water. In order to evaluate the effects of higher doses, animals were administered 50, 125, or 250 mg BDCM/kg/d (mice) or 75, 150, or 300 mg BDCM/ kg/d (rats) via gavage. Under the conditions of these studies, no significant adverse effects on immune function were observed in mice. Despite some changes that were observed in non-antigen-specific immunity in rats, these experiments suggest that the immune system is not a sensitive target organ for BDCM toxicity.     

壳聚糖的制备条件及其大鼠体内的分布

以虾壳为原料，本文报道了制备条件对壳聚糖性能的影响，利用核磁共振，质谱等方法，测定了壳聚糖的分子结构，采用氚标记法，进行了＾３Ｈ－壳聚糖在大鼠体内的组织分布试验。     

用兔主动脉条研究小蘖碱和硝普钠对几种激动剂作用的影响

用离体家兔主动脉条观察Ber和NP的作用;NP降低血管条的基本张力,明显逆转由PE,HT、5-HT和KCl所引起的收缩,Ber仅逆转PE引起的收缩,对HT,5-HT和KCl引起的收缩无影响,也不影响血管条的基本张力。 Ber和Pra均阻断PE对血管条的收缩作用,两药的IC_(50)分别为30μM和0.2μM。 实验结果表明;NP非特异性逆转几种激动剂所致血管条的收缩,Ber仅逆转PE引起的血管收缩,其作用性质和Pra相似,提示Ber对血管条的α_1-肾上腺素受体具有选择性阻断作用。     

中药指纹图谱在中药品质评价和质量标准研究中应注意的若干问题

中药在中国虽然有上千年的实际应用历史,但如何保证中药的疗效是一个越来越需要迫切解决的问题。为了制订出可控的质量标准,以保证中药安全有效,近年来,国内外研究人员更加注意对中药材,中成药的质量评价研究,中药指纹图谱方法不失为一种非常有效的评价手段,其种类大致包括TLC、TLCS、HPLC、HPLC/MS,GC,GC/MS,HPCE,IR,NMR和X-射线衍射等,但更为广泛应用的方法目前以色谱为主。     

EFFECT OF 4-VINYLCYCLOHEXENE ON MICRONUCLEUS FORMATION IN THE BONE MARROW OF RATS AND MICE

This study was conducted to evaluate the potential of 4-vinylcyclohexene (VCH) to induce micronuclei in the bone marrow of mice and rats. Male and female Cr1:CD BR (Sprague-Dawley) rats and B6C3F₁/CrBR mice were exposed to VCH 6 hr/day for 2 days or for 13 weeks. In the 2-day study, mice were exposed by inhalation to 0, 250, 500, or 1000 ppm, and rats were exposed to 0, 500, 1000, or 2000 ppm. In the 13-week study, mice were exposed to 0, 50, 250, or 1000 ppm, and rats were exposed to 0, 250, 1000, or 1500 ppm. In each study, a separate group of mice was exposed to 1000 ppm 1,3-butadiene (BD) so that a comparison could be made between the two compounds. Likewise, cyclophosphamide was also included for rats as a positive control. Bone marrow was collected from VCH-exposed animals approximately 24 h and 48 h after the final exposure. There were no statistically significant increases in micronucleatedpolychromatic erythrocytes (MN-PCEs) among VCH-treated mice and rats at any dose level or sampling interval at either 2-days or 13-weeks. Also, no statistically significant difierences in the polychromatic erythrocytes (PCE) to normochromatic erythrocytes (NCE) ratios were observed 273 in any of the VCH-treated mice and rats compared to air-exposed animals. As expected, both the butadiene-treated mice and the cyclophosphamide- treated rats showed significantly more MN-PCEs than the control animals.     

BLOCKADE OF THE CENTRAL HYPOTENSIVE EFFECT OF CLONIDINE BY α-ADRENORECEPTOR ANTAGONISTS IN RATS, RABBITS AND DOGS

SUMMARY 1. Clonidine and three α-adrenoreceptor blocking agents were injected into the cisterna magna of rats, rabbits and dogs. Clonidine (1 μg. kg⁻¹) induced a fall in blood pressure in the three species.
2. Phentolamine, tolazoline and phenoxybenzamine (100 μg. kg⁻¹) induced a fall in blood pressure in rats, but only phentolamine was effective in rabbits, and none of these drugs significantly altered blood pressure in dogs when given intracisternally.
3. A subsequent administration of clonidine after recovery of blood pressure no longer decreased blood pressure in rats and rabbits.
4. In dogs the effects of clonidine were antagonized by tolazoline and phentolamine, but not by phenoxybenzamine.
5. These results indicate that clonidine stimulates central α-adrenoreceptors to produce a decrease in blood pressure, but the structure of these receptors may vary according to animal species.     

鳗鱼油精对胶原诱导的兔和大鼠血小板聚集和血栓素B2产生的影响

用比浊法和放射免疫法测定了鳗鱼油精对血小板聚集和血栓素Ｂ２产生的影响。结果表明，①体外试验：１０．４￣８３．３ｍｌ／Ｌ鳗鱼油精明显抑制胶原诱导的兔血小板聚集和血栓素Ｂ２（ＴＸＢ２）产生，前者的抑制率为２０．５％￣６４．２％，后者的抑制率为１８．２％￣６１．０％。鳗鱼油精的浓度与抑制血小板聚集和ＴＸＢ２产生的效力呈正相关性，同时血小板聚集的抑制率和ＴＸＢ２产生的抑制率之间也呈正相关性，三者的线性方程     

ASSESSMENT OF MOTOR ACTIVITY IN REGULATORY NEUROTOXICITY STUDIES: VALIDATION OF THE ETHOVISION VIDEO TRACKING SYSTEM IN RATS TREATED WITH AMPHETAMINE AND CHLORPROMAZINE

A novel automated computer imaging technique for assessing motor activity in rats to a standard acceptable for regulatory neurotoxicity studies is described. The Ethovision video tracking, motion analysis, and behavior recognition system is shown to reliably assess both increases and decreases in motor activity of rats treated with D-amphetamine sulfate or chlorpromazine hydrochloride, respectively, by demonstrating statistically significant treatment-related effects with each drug. It also has advantages over existing beam-breaking systems in ease of use and flexibility, and provides a permanent record on video tape of the subjects examined.     

呋喃唑酮和一些常用抗溃疡药对四种大鼠胃溃疡模型的影响

呋喃唑酮在较小剂量(20～50mg/kg)即能对三种大鼠胃溃疡模型(慢性醋酸型,消炎痛型,幽门结扎型)显示明显的保护作用,对消炎痛模型的保护作用尤为突出。本药对应激型溃疡模型无效。已知的治疗消化性溃疡药物—生胃酮,阿托品、甲氰脒胍及多虑平并不显示上述作用特色。呋喃唑酮和生胃酮对幽门结扎模型的保护有协同作用。此外还对胃液进行了生化分析。     

FURTHER INVESTIGATIONS ON THE INTERACTION BETWEEN α-ADRENOCEPTOR ANTAGONISTS AND THE CENTRAL HYPOTENSIVE EFFECT OF CLONIDINE IN RATS, RABBITS AND DOGS

1. The interactions between five alpha-adrenoceptor blocking agents and clonidine have been studied in rats, rabbits and dogs after intracisternal injections. 2. Dibozane, ethomoxane, azapetine, dibenamine and thymoxamine reduced blood pressure in rats and an antagonism of the hypotensive effects of clonidine was detected for the first four drugs. 3. In rabbits, azapetine, dibenamine, dibozane and ethomoxane were hypotensive while thymoxamine had no effect on blood pressure. Dibozane and dibenamine reduced the hypotensive effect of clonidine. 4. In dogs, azapetine, dibozane and ethomoxane reduced blood pressure, while dibenamine induced an increase in blood pressure and thymoxamine was without effect. Only dibenamine antagonized the blood pressure lowering effect of clonidine. A definite conclusion could not be drawn with azapetine due to its long duration of action of action in both rabbits and dogs. 5. These results suggest that the central receptors involved in the hypotensive effect of clonidine differ from many other central receptors and vary according to the animal species. In addition the alpha-adrenoceptor blocking agents appear not to have a unique site and mechanism of action on central cardiovascular control.     

利咽止咳冲剂对小鼠免疫功能的影响及抗炎作用的实验观察

采用中药利咽止咳冲剂(自拟方)治疗慢性咽炎获得显著疗效.实验在临床治疗的基础上结合慢性咽炎的发病机理,对该药的免疫调节和消炎作用进行探讨.结果显示:该药对实验动物具有明显的免疫调节及显著的抗炎作用.     

EVIDENCE FOR THE INHIBITORY EFFECT OF 5-HYDROXYTRYPTAMINE AT CENTRAL AND PERIPHERAL SITES ON OVULATION IN RABBITS

1. The effect of 5-hydroxytryptamine (5-HT) has been investigated on ovulation per se as well as on induced ovulation in rabbits. 2. 5-HT administered intracerebroventricularly (i.c.v.) did not induce ovulation per se. 3. The ovulation was induced by coitus, subcutaneous administration of progesterone and intravenous administration of cupric acetate. 4. Postcoital and progesterone induced ovulation was found to be blocked by i.c.v. administered 5-HT. 5. Cupric acetate induced ovulation was, however, not found to be blocked by i.c.v. administered 5-HT. 6. Intraperitoneal administration of 5-HT was found to block cupric acetate induced ovulation. 7. It is concluded that 5-HT exerts an inhibitory control over ovulation by acting at central as well as at peripheral sites in rabbits.     

EVALUATION OF THE DERMAL ABSORPTION OF AQUEOUS TOLUENE IN F344 RATS USING REAL-TIME BREATH ANALYSIS AND PHYSIOLOGICALLY BASED PHARMACOKINETIC MODELING

Toluene is a ubiquitous chemical that is commonly used for its solvent properties in industry and manufacturing, and is a component of many paint products. Because of its widespread use, there is potential for both occupational and nonoccupational dermal exposure to toluene. To understand the significance of these exposures, the dermal bioavailability of toluene was assessed in F344 male rats using a combination of real-time exhaled breath analysis and physiologically based pharmacokinetic (PBPK) modeling. Animals were exposed to toluene at 0.5 or 0.2 mg/ml aqueous concentration (0.05% or 0.02%) using a 2.5-cm-diameter occluded glass patch system attached to a clipper-shaved area on the back of the rat. Immediately following exposure, individual animals were placed in a glass off-gassing chamber and exhaled breath was monitored as chamber concentration in real time using an ion-trap mass spectrometer (MS/MS). The real-time exhaled breath profile clearly demonstrated the rapid absorption of toluene, with peak chamber concentrations observed within 1 h from the start of exposure. The PBPK model describing the exposure and off-gassing chamber was used to estimate a dermal permeability coefficient ( K p ) to describe each set of exhaled breath data. Regardless of exposure level, a single K p value of 0.074 - 0.005 cm/h provided a good fit to all data sets. These rat studies using aqueous toluene will form the basis for comparing the dermal bioavailability of toluene in various paint products and may ultimately aid in understanding human health risk under a variety of exposure scenarios.     

山苍子油对实验性心肌梗塞动物缺血性损伤的保护作用

The possible protective effect of the essential oil of Litsea cubeba (LOUR.) Pers (L. C. oil) on experimental myocardial infarction in rabbits and myocardial necrosis induced by isoprenaline in rats were evaluated. The present study demonstrated that the animals treated with the oil showed improvement of ECG ST segment or "J" point changes and a reduced number of development of new O wave. L. C. oil offered beneficial effect on infarct size as indicated by N-BT staining in rabbits. Furthermore, lowering of serum-free fatty acid concentration of rabbits suggest that L. C. oil had advantageous effect on myocardial metabolism. The precise mechanism involved in tile anti-infarct effect of the oil isbeing studied in our laboratory.     

Marquris法和薄层色谱法用于海洛因滥用者尿液中吗啡检测的对比研究

本文应用Marquris法和薄层色谱法,对110例海洛因滥用者戒毒期间尿液中吗啡进行对比检测。结果:Marquris法测出阳性35例,符合率为47.6％,薄层色谱法测出阳性63例符合率100％,差异有高度显著性(P<0.01)。说明薄层色谱法的敏感性、可靠性明显优于Marquris法。     

阿片类药物成瘾急性戒断期中医证候评定量表的信度、效度评定及修改意见

目的:对《阿片类药物成瘾急性戒断期中医证候评定量表》进行信度、效度评定,并针对量表的不足之处提出修改意见。方法:利用中药戒毒临床研究中使用该量表进行戒断症状评分时收集到的数据,对《阿片类药物成瘾急性戒断期中医证候评定量表》进行信度、效度评定。然后根据因子分析和条目筛选结果提出量表修改意见,最后完成修改后量表的信度、效度评定。同质性信度的检测方法为Cronbachα系数,结构效度评定采用主成分法配合最大正交旋转。条目筛选方法包括:重要性评分法、离散趋势法、相关系数法和专家评定法。结果:原量表中7个条目的原有分层与因子分析结果不一致。结合专家意见对量表结构进行调整后,得到21个条目的新量表。根据条目筛选结果,建议删除重要性、敏感性、代表性均较差的3个条目。对修改后量表进行信度、效度评定,结果显示新量表较原量表具有更好的结构效度,条目归类也更为合理。总量表、毒瘀互阻证、寒证和热证因子层面的Cronbachα系数分别为0.740、0.676、0.420、0.681。结论:原量表的结构效度和部分因子的内部一致性较差,依据修改意见调整后得到的新量表具有更好的结构效度,部分因子的信度值提高,调整后的量表具有较好的信度和效度。     

中抗褐稻虱稻种抗性鉴定方法的研究

采用改良苗期群体筛选法,可将对褐稻虱具中抗水平的栽培稻和野生稻与感虫稻种区分开来。但如接虫量过大,则中抗稻种会被评为感虫。此外,当采用植株损害系数评价耐害性时,可用植株生长速率来代替原公式中的植株干物质比率。本法可提高工效,并且不会伤害植株,有利于抗虫品种的后代选育。