刺果甘草化学成分的研究

从刺果甘草(Glycyrrhiza pallidiflora Maxim)的根和根茎中分离到五种化合物,经理化性质和光谱方法鉴定,化合物P-2为4-羟基-2,4’-二甲氧基查尔酮,为一新的化合物,命名为刺果甘草查尔酮(glypallichalcone,P-2)。其它分别为4'-O-methyl-coumestrol(P-1),谷氨酸乙酰化物(N-acetylglutamicacid,P-3)和芒柄花素(formononetin,P-4),均为首次从该植物中获得。此外还得到β-谷甾醇(β-sitos-terol,P-5)     

Effects of morphine upon the pituitary-adrenal system and adrenal catecholamines: a comparative study in cats and rats

The aim of the present study was to investigate the effects of acute and chronic administration of morphine upon the pituitary-adrenal activity and adrenal catecholamines in rats and cats, two animal species with very different behavioural patterns of response to the opiate. Acute administration of the drug induced in both animal species an activation of the pituitary-adrenal system. Chronic administration of morphine to cats and rats induced a depression in the pituitary-adrenal function. No significant changes in the adrenal levels of catecholamines were observed in rats treated chronically with the drug. However, in the cat, the effects of morphine on adrenomedullary function seemed to depend on the stage of morphine treatment. The behavioural patterns of response in both animal species during chronic administration of the opiate, as well as the effects of induced withdrawal with nalorphine (an antagonist of morphine), indicated that dependence on morphine had developed, not only in the rats, but also in the cats. Acute morphine administration had a sedative effect, while in the cats the opiate produced a species-specific manic response characterized by hyperexcitement and aggressive behavior.     

Contribution of NMDA and nonNMDA glutamate receptors to synchronized excitation and cortical output in the primary motor cortex of the rat

Application of a GABA (gamma-aminobutyric acid) type A receptor antagonist through a microdialysis probe into the forelimb primary motor cortex (MI) of ketamine anesthetized rats induced the appearance of paroxysmal field potentials recorded in the supragranular layers of the MI and concomitant electromyographic (EMG) activity in the contralateral forelimb. Application of a nonNMDA (N-methyl-d-aspartate) glutamate receptor antagonist in conjunction with the GABA type A receptor antagonist completely blocked the paroxysmal field potentials and the EMG activity of the contralateral forelimb, while a NMDA receptor antagonist had no effect. The results indicate that the spread of activity within the primary motor cortex and the motor cortex output are mediated by nonNMDA receptors.     

Naloxone influences retention behaviour depending on the degree of novelty inherent to the training situation

The effects of immediate posttraining subcutaneous administration of naloxone (0.25, 1 or 5 mg/kg) on retention behaviour of rats trained in an inhibitory avoidance task, subjected or not to familiarization with the training situation prior to the training trial (pretraining) have been investigated. Naloxone did not influence performance of pretrained rats not subjected to footshock at training. The drug did not significantly modify retention latencies of pretrained rats subjected to a weak footshock. However, administration of naloxone facilitated retention behaviour of non-pretrained rats subjected to a weak footshock. Likewise, naloxone significantly increases retention latencies of pretrained rats subjected to a high footshock at the training trial. These data indicate that naloxone influences retention behaviour depending on the degree of novelty linked to the training situation: a facilitatory effect of the drug is observed when the training trial becomes associated with a clear novel situation for the animals (high footshock in pretrained rats or a weak footshock in non-pretrained animals).     

Serial measurements of a plasma prostacyclin inhibitor in a patient with recurrent abortions and lupus anticoagulant; a case report

Defective plasmatic stimulation of prostacyclin (PGI2) production by vascular cells has been described in patients with lupus anticoagulant (LAC). A young woman with recurrent abortions, LAC and evidence for deficient PGI2 production was studied. Serial measurements of a plasma PGI2 inhibitor, LAC and anticardiolipin antibodies (ACA) have been performed before and throughout her fourth pregnancy. Antenatal care and treatment with prednisone and heparin started at 10 weeks gestation. The plasma of our patient continued to inhibit PGI2 production by vascular cells despite treatment. The presence of inhibitor(s) of PGI2 release was confirmed by mixing the patient's plasma with normal plasma. In addition, an IgM lupus anticoagulant fraction (but not the IgG fraction) interfered with the release of arachidonic acid in human endothelial cells induced by thrombin. Despite prednisone and heparin treatment we did not find a complete correction of the LAC activity and the ACA (IgM type) still remained positive before the detection of a fetal death at 26 weeks. The placenta showed abundant infarcts and areas of ischaemic necrosis. We suggest that the defect in vascular PGI2 release could compromise fetal outcome.     

阿魏酸钠对花生四烯酸代谢的影响

利用放射薄层方法测定兔血小板花生四烯酸代谢产物TXB₂,PGE₂和PGF_2α。用放射免疫法测定兔血小板TXB₂及主动脉6-keto-PGF_1α。阿魏酸钠(SF,0.1～3.2 mmol/L),抑制¹⁴C-花生四烯酸转化为TXB₂,呈剂量效应关系,IC₅₀为0.762 mmol/L。SF在较高浓度(0.8～3.2mmol/L)时亦抑制PGE₂,PGF_2α的生成。用放免法观察到,SF对血小板TXB₂和动脉壁6-keto-PGF_1α的生成均有抑制作用,对TXB₂的作用较强。结果提示,SF可抑制兔血小板和动脉壁环氧酶活性。     

Adrenocortical response to acute and chronic ethanol administration in rats

Acute ethanol administration (2 g/kg IP) induced a significant rise in serum corticosterone levels which seemed to be related to blood ethanol concentration. Chronic ethanol administration, in the form of a liquid diet for 16 or 30 days, did not alter the levels of serum corticosterone. Chronic treatment of rats with a liquid diet containing ethanol resulted in the development of tolerance.     

Role of arachidonic acid metabolism on corticotropin-releasing factor (CRF)-release induced by interleukin-1 from superfused rat hypothalami.

The present work shows that the corticotropin-releasing factor (CRF)-releasing activity of interleukin-1 (IL-1) is partially inhibited by a phospholipase A2 (mepacrine) or a cyclooxygenase (indomethacin) inhibitor, but is not affected by inhibition of the lypoxygenase pathway with norhydroguaiaretic acid. These results indicate that the metabolism of arachidonic acid plays an important role as mediator of the effects of IL-1 on CRF release. It is also shown that products of the cyclooxygenase activity such as prostaglandins can stimulate CRF secretion by a direct action on the hypothalamus. Whereas PGE2 failed to induce increases on CRF release, PGF2 alpha stimulated in a dose-dependent manner (21-340 nM), the CRF release from continuous perifused hypothalami. It is suggested that PGF2 alpha could be involved as a messenger in the hypothalamic CRF secretion induced by IL-1.     

Pericholecystic hepatic activity in cholescintigraphy

Gallbladder nonvisualization in cholescintigraphy has been shown to be a reliable finding in acute cholecystitis. In some cholescintigrams, we have observed faintly increased pericholecystic hepatic activity in conjunction with gallbladder nonvisualization. To determine the frequency and significance of the pericholecystic hepatic activity finding, we evaluated 334 consecutive adult patients who had cholescintigrams with technetium-99m diisopropylphenylcarboamoyl iminodiacetic acid. Pericholecystic hepatic activity was seen in 21% of the abnormal scans demonstrating gallbladder nonvisualization but in none of the other scans. Thirteen of these patients underwent surgery; 11 (85%) were found to have acute cholecystitis, and two (15%) had chronic cholecystitis. Four patients (31%) had acute gangrenous cholecystitis, and five (39%) had cholecystitis complicated by gallbladder perforation. The pericholecystic hepatic activity sign is not specific for gangrenous cholecystitis or gallbladder perforation but does reliably indicate inflammatory gallbladder disease and is associated with a relatively high incidence of cholecystitis complicated by perforation.