Pharmaceutical Sciences
Volume:17 Issue: 3, 2012

Evaluating the effect of HEMADO on injuries resulted from Ischemia-reperfusion and related mechanisms in isolated male rat heart, is the main purpose of this study. 42 male Wistar rats (250-300g) divided to six groups, each has seven members (n=7) as follow: without ischemia, control, drug, ischemia with ethanol, blocker and drug–blocker. The animals are anesthetized by Ketamine and Xylazine. The hearts were quickly removed and mounted on Longendorff apparatus and perfused by Krebs-Henseleit solution under constant pressure and temperature of 37 ºC. After 20 minutes of stabilization, Ischemic groups are also received 40 minutes of global ischemia and 90 minutes of reperfusion. In drug group, the hearts were perfused 25 minutes with Hemadoenriched Krebs-Henseleit before the Ischemia. Minimum dose of HEMADO was 0.1 micro mole per liter, hence work on three different groups which were obtained from this study, was applied. HEMADO increased LVDP and significantly caused to decrease end diastolic pressure of the left ventricle (P <0/05), and also increased dp/dt max. in the drug group, these effects of HEMADO meaningfully declined when used with blocker ofMitochondrial Potassium ATP Channels. The findings of this study indicated that Hemado couldprotect the heart against ischemia-reperfusion injury by enhancing the LVDP and decreasing the LVEDP. The cardioprotective effect of Hemado may be mediated in part by Mitochondrial Potassium ATP Channels

Diabetes mellitus is a serious pathologic condition that is responsible for major healthcare problems worldwide and costing billions of dollars annually. Oral insulin is one of the most exciting areas of development in the treatment of diabetes because of its potential benefit in patient convenience, rapid insulinization of liver, adequate insulin delivery avoiding peripheral hyper insulinaemia while potentially avoiding adverse effects of weight gain and hypoglycaemia. Several methods from relevant literature evaluated and their properties,advantages and limitations noted. Current review includes categorized methods which are used to optimize insulin for oral application. This review summarizes various oral insulin delivery systems. Because of the insulin delivery problems, novel approaches for insulin delivery are being explored, including oral drug delivery.For several decades, researchers have tried to develop oral insulin using various technologies without much clinical or commercial success.

There are different and sometimes paradoxical reports about the effects of adenosine agonists and antagonists (specially in i.p. administration) in withdrawal syndrome of morphine. In the present study, the effects of N6-cyclopentyladenosine (CPA, A1 receptor agonist) in morphine withdrawal syndrome were investigated on NMRI rats (200- 240 g). Dependency was induced by i.p. injection of increasing doses of morphine for nine days. One hour after the last dose of morphine, withdrawal syndrome (jumping, standing on feet, abdomen writhing,wet-dog shake, genital grooming and teeth chattering) was induced by i.p. administration of naloxone. To investigate the effects of A1 receptor agonist in morphine withdrawal syndrome, CPA (20, 40, 80, μg/5μl/rat) was administered by i.c.v. route. Data were analyzed with one way anova and independent t test. CPA decreased naloxone-induced jumping-standing on feet and abdomen writhing (P<0.001) in all doses, however wetdog shake (P<0.05), teeth chattering (P<0.001) and genital grooming (P<0.01) were decreased by CPA in 40 and 80 μg/rat. The results indicate that CPA can decrease all naloxone-induced withdrawal symptoms and the effects on jumping-standing on feet, teeth chattering and genital grooming were dose-dependent.

Cholinergic and dopaminergic systems of the brain play an important role in learning and memory.Previously shown that morphine, histamine and lithium induce state-dependent learning. In the present study, the effects of the dopaminergic receptor agonist apomorphine on scopolamine state-dependent learning were examined in rats. In this experimental study 200 adult male Wistar rats were used. Rats were anesthetized and then placed in a stereotaxic apparatus. Two stainless-steel cannuale were placed 1 mm above CA1 region of dorsal hippocamus. One week later animals trained in a step-through type inhibitory avoidance task. The drugs injected 5 min before training or testing. One-way analyses of variance (ANOVAs) followed by Tukey test, were used for analysis of the data. Pre-training intra-CA1 administration of scopolamine impaired memory retrieval on the test day. The memory impairment induced by pre-training injection of scopolamine was reversed by pre-test administration of scopolamine and/or apomorphine, suggesting scopolamine induced state-dependent learning and apomorphine influence this type of learninig. These results suggest that dopaminergic receptors of the dorsal hippocampal CA1 regions may play an important role in scopolamine-induced amnesia and scopolamine state-dependent memory.

Due to the side effects of chemical and synthetic antimicrobial agents and emerging increase inbacterial resistances, more studies have recently focused on characterization of novel potential natural antimicrobial agents of plant, animal and microbial sources. Such substances are thought to have more half life and fewer side effects. In the present study, biochemical composition and antibacterial effects of Teucrium polium essential oil have been evaluated against some bacterial pathogens of clinical importance. The chemical analysis of the essential oil by Gas chromatography/ mass spectrophotometer (GC/MS) shows the presence of 58 substances (90.48%) mainly including Bicyclodec-1-ene and 1,3-Cyclooctadiene Respectively. Minimum inhibitory concentration of the essential oil determined using resazurin as bacterial cell growth indicator shows the highest antimicrobial activities against Bacillus cereus and Pseudomonas aeruginosa. The highest MIC values were observed in cases of Escherichia coli and Salmonella typhimurium. These results indicate that this essential oil has a high potential of antibacterial effect and resazurin can be used as a good growth indicator for different bacterial pathogens. Therefore, it can be suggested to purify and evaluate the active substances of this essential oil for future application as antibacterial agent and food preservative to combat pathogenic and toxigenic microorganisms.

Microencapsulation is a well-known method used to modify drug release. In this study, propranolol hydrochloride and Eudragit RS or RL microcapsules were prepared in order to assess the suitability of them as oral sustained release dosage form. Microcapsules were prepared using emulsion solvent evaporation method.The effect of formulation variables (polymer: drug ratio, polymer type, inclusion of triethyl citrate) and increase in stirring rate were investigated on microcapsule characteristics (shape, percentage yield, drug entrapment efficiency,mean particle size and drug release). All microcapsules were spherical with smooth surface. Percentage yield and drug entrapment efficiency were more than 90% for most formulations. The mean particle size for most of microcapsules was about 800 μm. Increase in stirring rate reduced the mean particle size but it did not affect the release properties. The release rate of drug decreased with increase in polymer:drug ratio for both polymers however the release rate was faster for Eudragit RL microcapsules. Addition of triethylcitrate to Eudragit RS microcapsules did not have any considerable effect on the release rate of drug. Propranolol hydrochloride and Eudragit RS or RL microcapsules were successfully prepared by emulsion solvent evaporation method. Increase in polymer:drug ratio decreased the release rate of drug but due to high water solubility of propranolol HCl the release rate was nearly rapid even at 4:1 Eudragit RS:drug and therefore further reduction in release rate is still required to achieve sustained release of propranolol hydrochloride.

Diabetes mellitus is a metabolic disorder characterized by hyperglycemia and insufficiency of secretion or action of endogenous insulin. Hyperglycemia was associated with adverse effects on the brain activity and neuronal structural changes and impaired long-term spatial memory. Some studies have suggested that loganin as a plant-based drug has a plasma glucose-lowering action in normal rats. In this study the effect of chronic orally administration of loganin on spatial memory of diabetic male rats was evaluated. 21 male rats (250 - 300 g) were divided into 3 groups (control, diabetic and loganin- treated diabetic) groups. Diabetes was induced by single injection of streptozotocin in male rats (60mg/Kg, i.p). Loganin was administrated orally (40 mg/kg) and daily for 6 weeks. All groups were trained in Morris water maze for two consecutive days. Then learning parameters were compared between experimental groups. Our results showed that oral administration of loganin significantly(p<0.05) improved spatial learning and memory in diabetic rats. Loganin exhibits protective effect on spatial learning and memory in diabetic rats.