Lentiviral gene transfer to the nonhuman primate brain

Lentiviral vectors infect quiescent cells and allow for the delivery of genes to discrete brain regions. The present study assessed whether stable lentiviral gene transduction can be achieved in the monkey nigrostriatal system. Three young adult Rhesus monkeys received injections of a lentiviral vector encoding for the marker gene beta galatosidase (beta Gal). On one side of the brain, each monkey received multiple lentivirus injections into the caudate and putamen. On the opposite side, each animal received a single injection aimed at the substantia nigra. The first two monkeys were sacrificed 1 month postinjection, while the third monkey was sacrificed 3 months postinjection. Robust incorporation of the beta Gal gene was seen in the striatum of all three monkeys. Stereological counts revealed that 930,218; 1,192,359; and 1,501,217 cells in the striatum were beta Gal positive in monkeys 1 (n = 2) and 3 (n = 1) months later, respectively. Only the third monkey had an injection placed directly into the substantia nigra and 187,308 beta Gal-positive cells were identified in this animal. The injections induced only minor perivascular cuffing and there was no apparent inflammatory response resulting from the lentivirus injections. Double label experiments revealed that between 80 and 87% of the beta Gal-positive cells were neurons. These data indicate that robust transduction of striatal and nigral cells can occur in the nonhuman primate brain for up to 3 months. Studies are now ongoing testing the ability of lentivirus encoding for dopaminergic trophic factors to augment the nigrostriatal system in nonhuman primate models of Parkinson's disease.     

Cyclic GMP may potentiate lordosis behaviour by progesterone receptor activation

The purpose of this study was to test the hypothesis that cGMP acts as a progesterone substitute to facilitate lordosis in oestrogen-primed rats. Female Sprague-Dawley rats underwent stereotaxic surgery to place a 26-gauge guide cannula into the third ventricle. Bilateral ovariectomy was done at the same time as stereotaxic surgery. Five days later ovariectomized rats were primed with 2 microg estradiol benzoate 24 and 48 h prior to behaviour testing. Some animals were further injected with 200 microg progesterone 4 h before behaviour testing. A nitric oxide synthase inhibitor infused into the third ventricle before progesterone administration significantly reduced lordosis performance. 8-Bromo-cGMP, a cell permeable cGMP analogue, or saline vehicle was infused into the third ventricle of hormone-primed animals approximately 4 h prior to the first of 3-h behaviour tests. This cGMP analogue facilitated lordosis behaviour. We next used KT5823, a highly specific inhibitor of protein kinase G (PKG), to test the hypothesis that cGMP action is mediated by this kinase. In this experiment, KT5823 was infused 15 min before progesterone. KT5823 significantly decreased lordosis behaviour. RU486, a progesterone receptor antagonist, was used to assess whether the stimulatory effects of cGMP are mediated through the progesterone receptor. Oestrogen-primed animals were injected with 5 mg of RU486 or vehicle 60 min before infusion with 8-bromo-cGMP. RU486 significantly attenuated cGMP-facilitated lordosis behaviour. These data show that cGMP facilitates lordosis through activation of PKG and the progesterone receptor.     

正常眼共焦扫描激光多普勒视网膜血流图

目的　探讨共焦扫描激光多普勒视网膜血流图的临床应用价值。方法　应用Ｈｅｉｄｅｌｂｅｒｇ共焦扫描激光多普勒视网膜血流图仪对４８ 例（８２ 只正常眼）视乳头及视网膜血流灌注进行检测。结果　视乳头大血管血流量为２０３１４ ±７４７７,血流速为６ ２７２４３ ±２ ２６００７ ,红细胞移动速率为１３１４ ±２５８ ;视乳头筛板处的血流量为２６３６ ±１４７４ ,血流速为４６７９９ ±２７０１５ ,红细胞移动速率为１９３ ±１０７ 。颞侧视乳头盘沿的血流量为２２９０ ±１１３２,血流速为５１４５３ ±３７０２１,红细胞移动速率为１６９±１１２ ;鼻侧视乳头盘沿的血流量为２１７７ ±９８３,血流速为４９３２１ ±２９０２９,红细胞移动速率为１６５±０９０;颞侧与鼻侧比较差异无显著性（ｔ 值分别为０６８２ ５ ,０４１０ ４,０２５０ １,Ｐ＞ ００５） 。颞侧视乳头旁视网膜的血流量为３２５５ ±１３００,血流速为５５８６３ ±２９３４５ ,红细胞移动速率为１７８ ±０８３;鼻侧视乳头旁视网膜的血流量为２０６１ ±８９２ ,血流速为３５８６４ ±２１２６６ ,红细胞移动速率为１２     

Possible involvement of P-glycoprotein in biliary excretion of CPT-11 in rats.

In our previous work, we found that the biliary excretion of the carboxylate form of irinotecan, CPT-11, on rat bile canalicular membrane consists of two components, the low-affinity one being canalicular multispecific organic anion transporter (cMOAT). In the present study, we have investigated the high-affinity component by studying the uptake in canalicular membrane vesicles. The ATP-dependent uptake of the carboxylate form of CPT-11 was inhibited significantly by several substrates and/or modulators of P-glycoprotein, including PSC-833, verapamil, and cyclosporin A, at a substrate concentration of 5 microM, at which the high-affinity component is involved predominantly in CPT-11 transport. When the concentration of the carboxylate form of CPT-11 was 250 microM, at which the low-affinity component (cMOAT) is involved predominantly in its transport, the inhibitory effect of the above compounds was reduced greatly. Similarly, there was also much lower inhibition of the ATP-dependent uptake of S-(2,4-dinitrophenyl)-glutathione, a substrate of cMOAT, by the above compounds. Taurocholic acid, a substrate of canalicular bile acid transporter, failed to inhibit the uptake of CPT-11 at the substrate concentration of both 5 and 250 microM. These results suggest that P-glycoprotein may act as the high-affinity component in the biliary excretion of the carboxylate form of CPT-11 in rats.     

定志丸对东莨菪碱诱发大鼠被动回避反应的影响

唐·孙思邈《备急千金要方》的定志丸在防治记忆障碍作用上较《太平惠民和剂局方》记载的定志丸为佳。茯苓、远志、石菖蒲有协同人参之作用。《和剂局方》中的朱砂未见有改善学习记忆障碍的作用,故无组成方剂意义。     

Influence of propranolol and pindolol on the haemodynamic effects of papaverine,isoprenaline and noradrenaline in hypertensive patients

Summary The influence of two -adrenoceptor antagonists, propranolol and pindolol, on the haemodynamic effects of papaverine, isoprenaline and noradrenaline was investigated in 9 male patients with first degree essential hypertension. Propranolol and pindolol were given according to a doubleblind, crossover scheme. Heart rate and blood pressure were measured before and after each treatment. Propranolol 670 µg/kg i. v. reduced the supine and standing systolic blood pressures by 2.3% and 1.6%, respectively. Similarly, the intravenous administration of pindolol 35 µg/kg reduced supine and standing systolic blood pressure by 5.5% and 8.3% respectively (clinically insignificant). Neither drug affected diastolic blood pressure. Following propranolol, there were moderate reductions in supine and standing heart rates, respectively by 24% and 20% (p<0.001). Similarly, but to a lesser extent, pindolol reduced supine and standing heart rate by 12% and 17% (p<0.001). The effects of papaverine, which, at 1.5 mg/kg i. v. reduced systolic blood pressure by 5–10% and increased heart rate by 8–15%, were not significantly influenced by the -blockers. The blood pressure and heart rate responses to isoprenaline, on the other hand, were attenuated or inhibited by both -blockers. While the -blockers inhibited the -adrenoceptor component of noradrenaline, the pressor component of noradrenaline, which is mediated through the -adrenoceptors, was not influenced by propranolol, but was inhibited after pindolol. It is concluded that pindolol differs qualitatively from propranolol in that it inhibited both the -and -adrenoceptor effects of noradrenaline.Abbreviations BP blood pressure - ECG electrocardiogram - HR heart rate - ISA intrinsic sympathomimetic activity     

Subchronic toxicity of photomirex in the female rat: results of 28- and 90-day feeding studies

Photomirex (8-monohydromirex) was administered to female Sprague-Dawley rats at dietary levels of 0.2, 1.0, 5.0, 25.0 and 125 ppm. Food intake and body weight gain were significantly depressed at the 125 ppm level in the 28- but not in the 90-day study. Significant alterations were observed in some hematological and biochemical parameters at the highest dietary level in the 90-day study. Photomirex residues accumulated in a dose-dependent manner in perirenal fat, liver, brain, kidney, and spleen. Dose-dependent histotoxic effects were observed in liver and thyroid at and above 1 ppm; hepatomegaly was observed at 25.0 and 125 ppm. These results indicate that photomirex was approximately five times more toxic than mirex in terms of liver histology. When these results are compared with those observed in an earlier study in the male rat, it is evident that the female is less susceptible to photomirex than the male.     

Environmental controls on stomatal conductance in a shrub of the humid tropics

Leaves of Piper hispidum, a shrub native to the lowland tropics of Mexico, have a strong stomatal response to humidity that results in similar rates of water loss under a wide range of leaf-to-air water-vapor concentration gradients. Stomatal conductance of these leaves is insensitive to CO₂ concentration and increases in response to high humidity even in the dark.     

Hybrid Pharmacokinetic Models to Describe Anti-HIV Nucleoside Brain Disposition Following Parent and Prodrug Administration in Mice

Brain delivery of active anti-HIV compounds is important for successful treatment of the AIDS patient. As an initial step in predicting human brain drug concentrations, hybrid pharmacokinetic models were developed to characterize the disposition of anti-HIV nucleosides following parent and prodrug administrations in mice. Mouse data were obtained following intravenous administration of 3-azido-2,3-dideoxyuridine (AZddU or AZDU), 3-azido-3-deoxythymidine (AZT), and their dihydropyridine prodrugs (AZddU-DHP and AZT-DHP). Exponential equations were fitted to the serum concentration–time data for each species, including the pyridinium ion moieties, and subsequently used in differential mass balance equations describing the brain dynamics of each compound. Model parameters for the mass balance equations were estimated by various techniques, including the utilization of in vitro data. In general, model-predicted brain concentrations agreed with the observed data. Similar data in larger animals will permit scale-up of the current model to predict human brain drug concentrations.