[Protective effects of Desmopressin acetate on retention of spatial memory deficits induced by post-traumatic stress disorder in Rats]

Post-traumatic stress disorder [PTSD] impairs spatial learning and memory. Desmopressin acetate ameliorates the cognitive deficits induced by electroconvulsive shock. This study was designed to evaluate the protective effects of Desmopressin acetate on retention of spatial memory deficits induced by post-traumatic stress disorder in rats. In this experimental study twenty one male Wistar rats were used. Animals were trained for 5 consecutive days in Morris water maze and then were randomly assigned in three groups [Vehicle + Sham, Saline + PTSD and Desmopressin acetate + PTSD] and tested in a probe 60 sec in 24h after the last acquisition trial. The groups of PTSD+Desmopressin acetate rats and vehicle+sham, saline+PTSD were injected Desmopressin acetate [10 micro gr/kg body weight] and saline [IP], respectively. Injections performed ten minute prior to PTSD and spatial memory was tested ten minutes later. Data were analyzed using SPSS-16, One-Way ANOVA and Tukey tests. The platform location latency of the Desmopressin acetate+PTSD group was significantly shorter [4.24 sec] than the control group [P<0.05] and also, had significantly smaller average proximity values [33.87 cm] compared to the saline+PTSD group [P<0.05]. Desmopressin acetate + PTSD spent significantly more time [21.65%] in the target zone [P<0.05]. This study indicated that Desmopressin acetate blocks the ability of PTSD to impair spatial memory retention

[To investigate the effect of portulaca oleracea L. and melissa officinalis L. extract on sleeping time in mice]

Portulaca oleracea [PO] and Melissa officinalis [MO] overgrow in the different parts of Iran. In previous studies, systemic administration of the extracts of PO and MO induces antinociceptive, anxiolytic and anticonvulsive, sedative effects in animals. This study was designed to evaluate different doses of the aqueous decoction extracts of PO and MO on sleeping time on mice. Male albino mice [25-30 g] were used in this study. The animals divided to control [saline], PO [25, 50 and 75 mg/kg] and MO [5, 10 and 25 mg/kg] groups [by IP injection]. For measuring of sleeping time we used Angle method. The results have shown that three doses of PO and two doses of 10 and 25 MO significantly increased sleeping time [p=0.000]. This finding showed that PO and MO may be play important role on the modulation of sleeping time

[Anxiolytic effects of the aqueous extracts of spinach leaves in mice]

Previous studies have shown the effect of antioxidant properties of spinach on delaying the aging process of CNS and age related cognitive function and some neurodegenerative diseases. This study was designed to evaluate the anxiolytic effects of different doses of aqueous extracts of spinach leaves. This study included fifty male mice [Wt: 25-30 g] which were divided into three experimental and two control groups. Different doses of the spinach extract powder [0.05, 0.10 and 0.15 g/mice] were given to the experimental groups for one month. Also, one of the control groups received water and the other one sucrose 3% [w/v] for one month. In order to increase the activity and curiosity of the mice, they were put inside a box with black walls for five minutes. Then the animals were transferred to the elevated plus maze in regular time intervals and evaluated for standard indexes of anxiety reaction for five minutes. The results of this study showed that percentage of open time was significantly increased in doses of 0.10 and 0.15, and the number of open arm entries was more with a dose of 0.15 g of spinach extract in comparison to the control group [P<0.05]. Furthermore, no significant differences were found in the total number of arm entries between the groups. In comparison to the control group, the number of SAP was significantly reduced with doses of 0.10 and 0.15 g of spinach extract in the experimental group [P<0.05]. It is concluded that higher doses of aqueous extract of spinach can decrease anxiety

effect of aqueous extracts of purtulaca oleracea on withdrawal syndrome in mice

Purtulaca pleracea [PO] overgrows in the different parts of Iran. In previous studies, the extract of P.O showed antinociceptive, anxiolytic and anti inflammation effects in Mice and rats. This study was designed to evaluate different doses of the aqueous extracts of PO on withdrawal syndrome on mice. In this study, 40 male albino mice [25-30 gr] were used. Morphine was used to produce drug dependency by Marshall Method [10 doses of drug in four days]. Different doses of the extract. [25, 50, 75 mg/kg IP] were injected to the separated groups and saline [10 ml/kg-ip] were injected to the one control group 30 min before of noloxone 2 mg/kg. The number of Jumping and amount of weight losses were used for assessment of classic withdrawal syndrome sign. The results indicated that the extract of PO significantly decreased the number of Jumping [p= 0.000] and also weight losses in 25 mg doses of extract [dose-dependent] in mice [p=0.045] It is concluded that the aqueous extract of PO may be play an important role on the modulation of withdrawal syndrome in mice

Evaluation of topical Matricaria chamomilla L. oil extract activity on linear incisional wound healing in albino rats

There are some information about antimicrobial and anti-inflammatory effect of Matricaria chamomilla flower oil extract, but there isn't any information about its effect on linear incisional wound healing. In this investigation, the effect of Matricaria chamomilla flower oil extract on linear incisional wound healing was studied. Thirty male Wistar rats were subjected to a linear 3cm incision made over the skin of the back. The animals were randomly divided into 3 experimental groups, as Sham operated, Control [Olive oil] and treatment. Sham group did not receive any treatment. Control group received topical olive oil twice a day from beginning of experiments to complete wound closure. Treatment group were treated topically by M. chamomilla extract dissolved in olive oil at the same time. For computing the percentage of wound healing, the area of the wound measured at the beginning of experiments and the next 2, 5, 8, 11, 14, 17 and 20 days. The percentage of wound healing was calculated by Walker formula after measurement of the wound area. Results showed that there were statistically significant difference between treatment and Control animals [p < 0.05] in most of the days. We conclude that the topical administration of M. chamomilla extract has wound healing potential in linear incisional wound model in rats

Assessing the effect of aqueous extract of the cuminum cyminm seed on the acute peripheral pain in hot plate and tail flick models in mice

Background and Purpose: Cuminum Cyminm [CC] is one of the plants whose aqueous extract is used in traditional medicine as anti-convulsive, anti-epileptic and as a tretment for some visceral pains. However, no substantial reports can be found of its effects on the peripheral pain in lab animals. Therefore, this study was condcated to determine the eefects of the IP injection of the aqueous extract of CC on the acute peripheral pain in Hot Plate [HP] and Tail Flick [TF] tests in mice

Methods and Materials: This experimental study was conducted on 56 male Albino mice [8 groups each with 7 mice] weighing 25-30 gr. 200 and 500 mg/kg of the aqueous extract of CC or saline of the volume were injected intraperitoeally 30 minutes prior to the tests. Pain measrment criteria in the TF test was the response time to the pain by raising the tail, and in the HP test the time to begin to lick the front legs or raising the rear feet

Results: The IP injection of the CC aqueous extract with the doses of 200 and 500 mg/kg significantly increasd the response time to the pain in HP and TF tests [P<0.01] in cmparison with the control groups and the group receiving saline. The efect was however more remarkable with the 500 mg/kg dose

Conclusion: The results of this study indicated that the aqueous extract of CC reduced the acute peripheral pain in the mice

effects of aqueous extracts of Melissa Officinalis on withdrawal syndrome in rats

Melissa officinalis [MO] grows in the different parts of Iran abundantly. In previous studies, the extract of MO has been reported to have antinociceptive and anticonvulsive effects in rats. This study was designed to evaluate the effect of different doses of the aqueous decoction extracts of MO on withdrawal syndrome in rats. 40 male albino rats [25-30 gr] were selected for this study. Morphine was used to produce drug dependency by Marshall method [injection of 10 doses of drug in four days]. 30 min before injection of naloxone [2 mg/kg], different doses of the extract [5, 10, 25 mg/kg] were injected intraperitoneally and saline [l0ml/kg IP] was injected into the rats of control group. Assessment of classic withdrawal syndrome was based on the number of jumps and the weight of the fecal material for every rat. The results of this study indicated that injection of doses of 10, 25 mg/kg of the extract led to a significant decrease in the number of Jumps [p=0.005] and also in the weight of feces of the rats [p=0.01]. We conclude the aqueous extract of MO can have an important role in the reduction of the severity of withdrawal syndrome in rats

[ effect of dexamethasone on anxiety related behavior in mice]

Previous studies have suggested that activation of the glucocorticoid receptors may have a modulatory effect on fear and anxiety. Therefore, the aim of this study was to determine the role of glucocorticoid hormones on modulation of anxiety in elevated plus-maze model in mice. In this experimental study, 60 male mice [25-30 g] were included. They were randomely divided into test and control groups. The test group received different doses of dexamethasone, as an agonist of glucocorticoid receptors, at 0.1, 0.3, 1, 2 and 10 mg/kg, Subcutaneausly, and the control group received the same volume of 2% ethanol in normal saline 30 minutes before the evaluation of their behavior. Twenty five minutes after the injection, the mice were put in a black box for 5 minutes to induce their activity and stress. The animals were then individually transferred to a standard elevated pluse-maze in regulated time and the percentage of time spent in the open arms and the ratio of open arm entries to total entries in 5 mins was measured. Results indicated that dexamethasone with the doses 0.3 and 1mg/kg, significantly reduced anxiety in mice [p<0.01]. However, this effect was not observed at 0.1 and 2mg/kg. Our findings also showed that denamechasone at the dose of 10 mg/kg increased anxiety behavior in mice [p<0.01]. The findings of this study indicated that glucocorticoids have important role in modulation of anxiety related behavior in a dose dependent manner using an elevated plus maze model in mice

Effects of aqueous extract of fruit of Foeniculum vulgar on neurogenic and inflamatory pain in mice

Results of some of previous investigations showed that the aqueous extract of fruit of the Foeniculum vulgar [FV] has many medical effects. The aim of this study was to assess the role of Aquinus extract of fruit of FV on acute and chronic pain in formalin test in mice. In this study 42 male albino mice of 25-30 gr. weight were devided into 6 groups. FV [100, 200, 500 and 1000 mg/kg] and saline were injected intraperitoneally 30 min before formalin test. The criteria for pain assesment after injection of formalin 5% [25microl] in the right paw of the mice were the durations of licking and elavation of foot [5 min for acute pain and 15-40 min for chronic pain]. The results of this study indicated that all doses of Fv have analgesic effect on pain in acute and chronic phases [p<0.05]. FV can reduce acute and chronic pain after formalin injection. Further studies are required to determine the mechanism [s] of inhibitory effect of FV on pain sensation

[ effects of cimetidine on motor activity: an evaluation the role of opioid receptors]

Effects of cimetidine [CIM] on locomotor is controversial. This study was designed to evaluate the effects of CIM on motor activity and possible roles of opioid receptors in CIM-induced decrement in locomotor activity in mice. Thirty-six male mice [25-30gr] were divided into six groups in this study. Locomotor activity was evaluated using an automated activity monitor system. CIM [50 mg/kg, i.p.] was injected 25 min before testing in presence or absence naloxone [2 mg/kg, sc]. Morphine [5 mg/kg, i.p] was injected 25 min before testing in the presence or absence CIM. Decreased motor activity significantly. Pretreatment of or morphine did not change CIM - induced response significantly. The results showed that CIM significantly decreased motor activity in mice [P=0.000]. Pretreatment of nalxone did not change CIM-induced response significantly. Morphine alone did not change motor activity. Pretreatment of CIM did not change morphine-induced response. Data indicated that cimetidine can reduce motor activity independence from interaction with opioid receptors

[Verapamil enhances the impairing effects of stress on retrieval of long-term memory in rats]

This study investigated an interaction between acute restraint stress and verapamil, as a blocker of L-type voltage sensitive channels on retrieval of long-term memory. Young adult male rats were trained in one trial inhibitory avoidance task [1mA, 1.5s footshock]. On retention test given 48 hr after training, the latency to re-enter dark compartment and time spent in light chamber of the apparatus were recorded. Thirty min before retention test, the rats were exposed to a 10 min of restraint stress in a Plexiglass with or without prior treatment of verapamil [5, 10, 20 mg/kg]. The results showed verapamil pretreatment enhanced the impairing effect of stress on memory retrieval. The applied stress increased circulating corticosterone levels as assessed immediately after the retention test, indicating that stress-induced impairment of memory retrieval is mediated, in part, by increased plasma levels of glucocorticoids. Verapamil did not affect on this response. These findings indicate that acute restraint stress impair retrieval of long-term memory, and provide evidence for the existence of an interaction between stress and L-type voltage calcium channels on this process

[Anxielytic effects of portulaca oleracea aqueous extracts in mice]

Portulaca oleracea [PO] overgrows in different parts of Iran. In previous studies, a 10% hydroalcoholic extract of the PO aerial parts [leaf and stem] showed anticipative and anticonvulsive activity in rats. This study was designed to evaluate anxielytic effects in different doses of the aqueous decoction extracts of PO seed. In this study, forty male mice [25-30gr] were used in a model elevated plus maze [EMP]. Different doses of the extract [25, 50, 75 mg/kg] were injected intraperitoneally [IP] to three separated test groups and normal saline [10 ml/kg, IP] was injected to one control group, intraperitoneally. For increasing their activity, animals were put inside a black box for 5 min. Then they were transferred to the elevated plus maze and evaluated for their anxiety reaction, including number and percent of time spent in open arm. Results indicated that injection of the extract in three doses of PO reduced anxiety reaction in test groups, compared with the control group which had higher number of entrances and spent more time in open arm [P=0.000]. It is suggested that the aqueous extract of PO plays an important role in fear and anxiety reactions and that the anxielytic effects of PO is not related to the dosage of use

Effects of aqueous extract of seed of Coriandrum sativum on acute pain in mice

Since use of synthetic drugs for relief of pain has many side effects, today medical plants are becoming more prominent as substitute therapeutic agents. Previous findings indicate that Coriandrum sativum [CS] modulates pain in both animal and human. The present work investigated the effects of CS seed on acute pain using hot plate and tail flick models. Albino mice [25-30 g] were used for this study. Aqueous extract of CS seed was injected in doses of 100 and 200 mg/kg 30 min before test. The analgesic effect of the drug on acute pain was evaluated using Hot plate and Tail flick models. Results indicated that CS has analgesic effect in both doses in both models and higher dose of the drug was more effective [p<0.01]. The findings above showed that CS could modulate acute pain. Further research is required to determine the mechanisms by which CS has an inhibitory effect on pain sensation

[Anti-nociceptive effects of the aqueous extracts of Portulaca Oleracea seeds in mice]

Portulaca oleracea [P.O] overgrows in the different parts of Iran, that is used there as both a salad green and a medicinal plant. In previous studies, a 10% ethanolic extracts of the aerial parts [Leaf and stem] of PO showed anti-nociceptive activity in mice and rats. This study was designed to evaluate anti-nociceptive effects of different doses of the aqueous decoction extracts of PO [Seed]. In this study, 65 male mice [25-30 gr] in model tail flick were used. Different doses of the extract 25, 50, 75, 100 mg/kg [IP] were injected to the separated groups of four [Test group] and water [10 ml/kg-IP] was injected to the one control group. The anti-nociceptive effect was determined 15 and 30 min after injection [N=15 mice for pilot study]. The results showed that there was a significant difference between two groups [P<0.05], but the animals of test groups did not show significant difference in different doses and time. It is concluded that the aqueous extract of PO has anti-nociceptive activity, which is not related to dose and time

[Assessment of hydroalcoholic extract of thymus vulgaris on neurogenic and inflammatory pain in mice]

The side effects of anti-nociception chemical drugs caused notice to medical plants. This study was performed to investigate the effects of hydroalcoholic extract of Thymus vulgaris [TV] on neurogenic and inflammatory pain in formalin test in mice. 40 male albino mice [20-30 gr] were used. TV [100, 500 mg/kg] as extract and saline were injected 30 mine before formalin test. Indexes for evaluation were duration of licking and foot elevation for assessment of acute pain [5 min] and chronic pain [15-40 min] after injection of formalin 5% [25 microl] in paw. Results indicated that TV has analgesic effect in both doses [P<0.01], and higher dose [500 mg] was more effective. Findings showed that hydroalcoholic extract of TV can modulate acute and chronic pain. Further research is required to determine the mechanisms by which TV has an inhibitory effect on pain sensation

[Effect of systemic injection of vasopressin on anxiety in plus maze in mice]

Introduction: Previous studies indicated that vasopressin as a neurotransmitter can have a role in modulation of anxiety reactions

Objective: The present study was designed to evaluate the role of vasopressin as a neurotransmitter on the fear and anxiety in plus maze model

Materials and Methods: Male albino mice [mean weight of 25-30 g] were used for these experiments. First animals were randomly divided into three control and experimental groups. Then 5-10 microg/kg vasopressin was administered to experimental group and same amount of normal saline was given to control group ten minutes before the experiment. And in order to increase their movement and curiosity, they were put inside the black wall box for 5 min. Then animals were transferred to the Plus Maze and evaluated their anxiety reaction through observing the standard index of anxiety assessment

Results: Results indicated that injection of vasopressin in both doses reduced anxiety reaction as compared to saline group and in the test group animals have more number of entrances and spent more time in open arm [P<0.01]

Conclusion: The above results show that vasopressin plays an important role in reduction of anxiety in Plus Maze model

Assessment the effects of hydroalcoholic extract of Thymus vulgaris acute pain in hot plate and tail flick in mice

Since uses of antinoceception chemical drugs for relief of pain have many side effects; today medical plants are very noticeable. The present work investigated the effects of Hydroalcoholic extract of Thymus vulgaris [TV] on acute pain in Hot plate and Tail flick models. Albino mice [20-30 gr] were used for this study. Hydroalcoholic extract of TV seed was injected in doses of 100 and 500 mg/kg 30 min before test. Then the analgesic effect of the drug on acute pain was evaluated using Hot plate and Tail flick models. Results indicated that TV has analgesic effect in both doses in both models [P<0.01], and higher dose of the drug was more effective. These findings showed that TV could modulate acute pain. Further research is required to determine the mechanisms by which TV has an inhibitory effect on pain sensation