Inhibition in carotid body chemoreceptors mediated by D-2 dopaminoceptors: Antagonism by benzamides

Inhibition of chemosensory nerve impulses in the cat is evoked by dopamine (DA) applied to carotid body chemoreceptors. Pharmacological characterization of the dopaminoceptors involved in this action was determined through their blockade with benzamides, selective antagonists of D-2 receptors. Both metoclopramide and sulpiride were effective blockers of DA-induced chemosensory inhibition. Furthermore, both drugs induced an immediate increase in the frequency of carotid nerve chemosensory impulses, suggesting the presence of previous tonic inhibition of chemoreceptor discharges by endogenous DA released from glomus cells.     

Growth and adipogenic differentiation of mesenchymal stromal bone marrow cells during culturing in 3D macroporous agarose cryogel sponges

We studied the possibility of population of macroporous agarose cryogel sponges by mesenchymal stromal bone marrow cells with their subsequent adipogenic differentiation. After 7-day culturing of mesenchymal stromal cells in agarose cryogel, the level of cell proliferation was 35%. After 3-week culturing in a medium inducing adipogenesis we observed accumulation of intracellular neutral lipids positively stained with Oil Red O. These findings can be used for the development of bioengineering constructions of the adipose tissue on the basis of spongy carriers. Translated from Kletochnye Tehnologii v Biologii i Medicine, No. 3, pp. 141–144, August, 2008     

Endogenous brain angiotensin II disrupts passive avoidance behavior in rats

The presence of angiotensinogen, the precursor of angiotensin II (ANG II), in brain tissue and in cerebrospinal fluid (CSF) allows stimulation of endogenous brain ANG II by renin. Passive avoidance tests were performed in female Wistar rats. The animals received an electrical shock after entering a black box on the first experimental day. Avoidance was tested every 24 h for 5 consecutive days. Renin in doses of 0.01 and 0.1 units was injected once into the lateral brain ventricles 2 min before the first test. CSF ANG II increased from 40 to 4547 and 5152 fmol per ml (means), respectively. A dose-dependent disruption of avoidance learning was observed, the frequency to enter the black box increasing from 11% (control) to 29% and 46%, and the latency decreasing from 165 (control) to 143 and 116 sec, respectively. These effects were statistically significant (P less than 0.001) for more than 24 h and returned to control levels after 48 to 120 h. Administration of the converting-enzyme inhibitor SQ 14225 i.v.t. prior to renin injections abolished the renin effects. Injections of renin given 22 h after learning were without effect.     

血液灌流对硫线磷和硫酸阿托品的吸附作用

目的 定量研究血液灌流对有机磷农药硫线磷和其解毒药阿托品的吸附作用.方法 模拟临床血液灌流装置,对含硫线磷和硫酸阿托品的血样进行灌流吸附,分别用毛细管气相色谱法和高效液相色谱法测定硫线磷和硫酸阿托品的残留量.结果 吸附剂用量为0.5、1.0和1.5 g,包膜活性炭在灌流2.0 h后硫线磷的清除率均能达到90%以上,硫酸阿托品的清除率依次为61.9%、84.9%和88.9%;HA230树脂在灌流1.5 h后硫线磷清除率都达到90%以上,硫酸阿托品的清除率也依次高达88.0%、97.2%和98.4%;包膜活性炭灌流3.0h后,硫酸阿托品与硫线磷的比值最高为灌流前的10.1倍,而HA230树脂灌流后,此比值最高为灌流前的6.7倍.结论 包膜活性炭和HA230吸附树脂血液灌流1.5～2.0 h均能清除血中大部分硫线磷,而且均能增加血中硫酸阿托品和硫线磷浓度的比值.     

The effect of denervation of Merkel cells in cats

The morphology of Merkel cells in sinus hair follicles of the upper lip (vibrissae with a circular blood sinus), and in touch domes of the glabrous skin of the nose, was investigated in cats up to 12 weeks after resection of the infraorbital nerve. Even 12 weeks after denervation there was neither an ultrastructural alteration of Merkel cells nor a reduction of their number in sinus hair follicles. Also in touch domes the Merkel cells did not disappear.     

心脑血管病患者微血栓与D－2聚体、血小板聚集的相互关系

观察２０例急性脑梗塞，３０例冠心病在微循环中微血栓的变化，同时检测血小板聚集率、Ｄ－２聚体。结果表明微血栓阳性组血小板聚集率、Ｄ－２聚体均高于微血栓阴性组。治疗后二组血小板聚集、Ｄ－２聚体明显减少。提示微血栓、Ｄ－２聚体及血小板聚集率可作为评定冠心病、脑梗塞病情变化的一种指标     

超声辅助大孔树脂技术富集荆芥穗中总黄酮和总酚的工艺研究

目的 通过超声辅助大孔树脂对荆芥穗Schizonepetae Spica水提物中总黄酮和总酚类化合物进行富集并对比处理前后化合物含量及活性变化。方法 从7种不同类型树脂中筛选超声辅助最佳树脂型号,在吸附动力学和吸附热力学研究下,对超声温度、功率、上样质量浓度及解吸溶剂百分比等影响因素进行工艺优化。测定了优化处理前后各成分含量及活性变化。结果 动力学和热力学的研究表明,荆芥穗总黄酮适用于Langmuir模型,且吸附过程为自发吸热熵增,总酚则为自发放热熵减并适用于Freundlich模型,据此不同的吸附机制优化了2类成分同时富集的最佳工艺,在超声辅助AB-8大孔树脂,温度25 ℃、时间2.5 h,功率150 W,上样质量浓度0.1 g/mL,70%乙醇解吸附的过程下,荆芥穗水提物中总黄酮和总酚类化合物含量增加2～3倍,其单体成分的含量及抗氧化和神经氨酸酶抑制活性均显著增加。结论 超声辅助大孔树脂技术为荆芥穗总黄酮和总酚类成分的有效可行富集技术。     

阿奇霉素-离子交换树脂复合物的制备及其掩味与调控释药作用

为掩盖阿奇霉素(azithromycin,AZI)苦味和个性化调控药物释放速度以减少胃肠道刺激,分别以羟丙基纤维素(hydroxypropyl cellulose,HPC)和尤特奇RS100修饰制备速释型AZI-Amberlite^TM IRP64/HPC和缓释型AZI-Amberlite^TM IRP69/RS100进而组合以实现控制释放。对AZI-离子交换树脂复合物的载药量、药物利用率进行测定,通过差示扫描量热分析和X射线衍射对AZI-离子交换树脂复合物进行结构表征,测定其润湿度、掩味效果、体外溶出和释放行为。结果显示,形成的AZI-离子交换树脂复合物改变了药物原有的结晶状态,2.5%HPC修饰的AZI-Amberlite^TM IRP64/HPC和0.5%RS100修饰的AZI-Amberlite^TM IRP69/RS100掩味效果良好,两者以对应AZI含量为13∶67的比例组合可以实现AZI在前10 min的快速释放和后期的6 h内平稳释药。结果表明,经表面修饰制得的AZI-离子交换树脂复合物及其...