[ effect of intraperitoneally injection of matricaria chamomilla ethanolic extract on seizure]

Matricaria chamomilla [MC] has a series of flavonoid compounds with benzodiazepine-like properties. So it may be effective in the treatment of epilepsy and seizures. We evaluate the effect of intraperitoneally injection of hydroalcoholic chamomilla extract on seizures induced by pentylenetetrazole in male rats. In this study, 56 male rats [200 - 250 g] were divided into to seven groups [n = 8]: 1 - control [saline] 2 - MC 50 mg/kg, 3 - MC 100 mg/kg, 4 - MC 200 mg/kg, 5 - MC 500 mg/kg, 6 - Diazepam [0.2 mg/kg], 7 - Flumazenil [0.5 mg/kg] + MC 200. All groups received PTZ [65 mg/kg/ip] 30 minutes after material injection and the animal's convulsive behavior were recorded. The data were analyzed statistically by SPSS software with using one-way ANOVA followed by Tukey test. The administration of hydroalcoholic extracts of chamomile, delayed onset of tonic seizures in the animal's anterior limb and body at all used dosages. This effect was significant at doses of 200 and 500 mg/kg, in compare with control group. Also the extract of chamomile reduced the total duration of seizure and the duration of tonic -colonic seizures dose - dependently, that were significant at 100, 200 and 500 mg/kg of dosage. Intra-peritoneal administration of chamomile hydroalcoholic extract can effectively reduce seizures that induced by PTZ in rats. Here by, it is recommended to identify its effective components by conducting complementary research

[Dual effects of morphine on spontaneuse seizure activity in mouse brain hippocampal slices]

Opiates have complex effects on seizure activity. They have both anti-and proconvulsive effects depending on experimental conditions. The aim of this study was to determine the effects of different doses of morphine and naloxon on spontaneous seizure activity in mouse brain hippocampal slices. Spontaneous epileptic activity in the brain slices of mouse was induced by continuous perfusion of low magnesium artificial cerebrospinal fluid [low-Mg2+ACSF]. Extra cellular recordings were performed in the hippocampal CA1 pyramidal cell layer to account for the effects of the drugs on amplitude, duration and number of the ictal events as well as number of interictal spikes. Application of morphine had a biphasic effect on the recorded spontaneous seizure-like events. In a low concentration [10 micro M], morphine decreased seizure activity. Higher morphine concentrations [30 and 100 micro M] enhanced seizure activity in an apparent dose-dependent manner. Naloxone, a nonselective opiate antagonist, blocked the proconvulsant action of morphine. The results of this study showed that the effect of morphine on seizure in mouse is dose dependent. In other words, low systemic doses of morphine have anticonvulsant effects while high doses are proconvulsant

Dual effects of morphine on spontaneous seizure activity in mouse brain hippocampal slices

Opiates have complex effects on seizure activity. They have both anti- and proconvulsive effects depending on experimental conditions. The aim of this study was to determine the effects of different doses of morphine and naloxon on spontaneous seizure activity in mouse brain hippocampal slices. Spontaneous epileptic activity in the brain hippocampal slices of mouse was induced by continuous perfusion of low magnesium artificial cerebrospinal fluid [low -Mg[2+] ACSF]. Extra cellular recordings were performed in the hippocampal CA1 pyramidal cell layer to account for the effects of the drugs on amplitude, duration and number of the ictal events as well as number of interictal spikes. Application of morphine had a biphasic effect on the recorded spontaneous seizure-like events. In a low concentration [10 microM], morphine decreased seizure activity. Higher morphine concentrations [30 and 100 microM] enhanced seizure activity in an apparent dose-dependent manner. Naloxone, a nonselective opiate antagonist, blocked the proconvulsant action of morphine. The results of this study showed that the effect of morphine on seizure in mouse is dose dependent. In other words, low systemic doses of morphine have anticonvulsant effects while high doses are proconvulsant

effect of magnesium on morphine withdrawal signs in rats

Background and Purpose: Glutamatergic system has a role on morphine withdrawal sign, and magnesium has inhibitory effect on the NMDA receptors of glutamatergic system. The present study aimed to determine the effects of magnesium injection on morphine withdrawal signs in male and female rats

Materials and Methods: In this experimental study, 48 Male and female rats [200-250 gr] were used. The animals divided into 6 equal groups: two male and female control groups received normal saline; two male and female groups receiving magnesium sulfate 150 mg/kg; and the last two groups receiving magnesium sulfate 300 mg/kg. All groups received 3% sucrose in tap water with morphine 0.4mg/ml [for 21 days] to become addicted. In the end of 21st day, NS or magnesium administrated 30 min before naloxone [2mg/kg] and then withdrawal signs evaluated for next 30 min. The obtained data were analyzed in SPSS using ANOVA and complementary tests with p<0.05 as significant

Results: The results of this study showed that the injection of magnesium in dose of 150 mg/kg could significantly reduce many withdrawal symptoms in male addicted rats [Jumping 62.96% [2.5 +/- 1.14], standing 45.4% [6.62 +/- 1.45]] and in female addicted rats [Jumping 77.75% [1.25 +/- 0.54], climbing 24.51% [8.87 +/- 1.65], standing 52.57% [5.57 +/- 1.26]]. The injection of magnesium with dose of 300 mg/kg also reduced dramatically withdrawal symptoms in male rats [Jumping 87.03% [6.75 +/- 1.66], climbing 34.34% [12.87 +/- 1.27], standing 56.12% [12.125 +/- 1.27]] and female rats [Jumping 84.43% [0.875 +/- 0.25], climbing 36.17% [7.5 +/- 1.08], standing 69.07 % [3.75 +/- 0.64]]. The administration of magnesium in both doses caused a significant reduction of most withdrawal symptoms, and its effect on both sexes was almost similar

Conclusions: It seems that the injection of magnesium during morphine withdrawal can considerably reduce the symptoms of withdrawal syndrome in rats

[ effects of electromagnetic field on fertility and mouse gonads in preimplantation stage]

Considerable attention is focused on the effects of the electromagnetic field [EMF] due to its wide-ranging use in everyday life. Appliances and various equipments are sources of electromagnetic fields with a wide-range of technical characteristics. In this study we investigated the effect of EMF [50 Hz, 0.5 mT] on fertility and mouse gonads in preimplantation. Materials and Methods: Eighty female mice were divided in to 2 groups the control group was not exposed to EMF, while the case group was exposed to 4 hours per day, to 50 Hz and 0.5 mT EMF 6 days a week, for 2 weeks. On the 8th day of exposure, female mice in both groups were superovoulated and mated overnight. Next morning females with a vaginal plug were identified as pregnant mice at the time of implantation, the pregnant mice were sacrificed and blastocysts were subsequently obtained from these mice by flushing the uterus horns. The samples of ovaries in all groups were taken and were processed for light microscopic studies, and the data was compared using t-test [SPSS, considering, and P < 0.05], significant. Results: The mean number of pregnant mice decreased in the EMF group [50%] as compared to the control group [67.5%], difference not significant. The mean number of fetuses per pregnancy was 9 +/- 4.8 in the control group and 5.5 +/- 5.7 in the experimental group, with significant decrease between the means of the 2 groups [P < 0.03]. The analysis of the size of monolayer primary follicle in the EMF exposed groups did not show significant decrease compared to the control group [12.33 +/- 1.53, 12.17 +/- 1.79 and P>0.810]. Although the total number of follicles, number of monolayer primary follicles and corpus luteum, increased in comparison to control group following there was no significant differences between them. Conclusion: The findings indicated that the EMF, following short periods of exposure, has negative effects on female mice fertility, whereas histological studies showed no changes in ovaries

effects of ascorbic acid injection in to locus ceruleus and ventral tegmental area and PGi on morphine withdrawal signs in rats

Recent studies indicate that the glutamatergic and dopaminergic systems are involved in morphine withdrawal syndrome. Ascorbic acid [ascorbate] is an antioxidant vitamin released from glutamatergic neurons and modulates the synaptic action of dopamine and glutamate in the locus ceruleus, ventral tegmental area and PGi as well as behavior. To determine the effects of ascorbic acid injection into locus ceruleus, ventral tegmental area and PGi on morphine withdrawal signs in rats [MWS]. This was an experimental study in which a total of 80 male rats [250-300gr] divided into two were tested. The first group marked as control received 3% sucrose in tap water [n=10] and the second group [dependent group] received morphine and 3% sucrose in tap water [0.1, 0.2, 0.3, 0.4mg/ml each for 48h, and 0.4mg/ml for the remaining days up to day 21]. The latter was further divided into 7 subgroups as follows: [1] morphine group; [2, 3, and 4] sham operated groups which were surgically implanted with cannula at the locus ceruleus [LC], ventral tegmental area [VTA], and PGi; [5, 6, 7] morphine-ascorbic acid groups injected with AA [8 microg/microl] into LC, VTA, and PGi at day 21 and 5 min before naloxone administration. At the end of the training day, all groups received naloxone [2mg/kg I.P] and MWS was studied for 30 minute. Our results showed that the injection of ascorbate into LC and PGi caused a higher decrease in morphine withdrawal syndrome signs compared to VTA. Glutamatergic system is more effective than dopaminergic system in attenuation of MWS by acute injection of ascorbate

[ effects of prenatal morphine exposure on spatial learning]

Drug abuse during pregnancy is a growing problem in all developed countries worldwide. Maternal drug abuse affects the developing systems and the associated long-term effects can persist untill adulthood, decreasing the rate of their maturation. To determine the effects of prenatal morphine exposure on spatial learning Eighteen pregnant rats were divided into morphine, saline, and control groups. Morphine or saline was administrated [S.C] to female rats twice a day [at 12-hr intervals] during the days 11-18 of their gestational period [5 mg/kg morphine for the first 3 days and 10 mg/kg for further 5 days]. Pups [P90, n=6] were trained in an 8-arm radial maze apparatus.The data were analyzed statistically using Chi-square test. The results indicated that prenatal morphine exposure causes a reduction in the time needed to learn these trials however, they needed more time to complete regular trials. Prenatal morphine exposure impairs normal spatial learning

[ effect of Elaeagnus angustifolia L. leaves extract on pain of male rats]

For long time medical scientists have speculated about alleviation of pain so that they have attempted to prescribe a potent analgesic with the least side effects. There are some records in Iranian traditional medicine showing that Elaeagnus angustifolia L. decreases inflammation and pain. Therefore, in this study the analgesic effect of the aqueous extracts of E. angustifolia leaves was evaluated on male rats. The analgesic effect of the extract was studied using formalin test on 35 male rats. Decoction extracts of the leaves with 25, 50, 100 [mg/kgw/ip] concentration were prepared and used. The reaction of the extracts against pain were assessed in comparison to a routine non-steroid anti-inflammatory and pain drug [Diclofenac 5 mg/kgw/hp]. The extract had a significant and dose-dependent analgesic effect on both pain phases that were induced by formalin and it was more potent than the effect of Diclofenac. The extract of E. angustifolia leaves has the optimal reaction against pain and this effect is produced peripherally and centrally. The E. angustifolia leaves contain flavonoids and terpenoids and the analgesic effect of extract is probably from the anti-inflammatory reactions of these materials

[Effects of opiate receptor agonists and antagonists on spontaneous seizure activity in hippocampal slices]

Opiates have complex effects on seizure activity. They have both anti-and proconvulsive effects depend on their concentration. Low doses of morphine have anticonvulsant effects, while high doses have proconvulsant effects. Sudden morphine withdrawal results in shortterm proconvulsant effects. In the present, the effects of opioid receptors agonists and antagonists on spontaneous seizure activity in epileptogenic hippocampal slices were evaluated. Hippocampal slices [400 micro m] were prepared from young Wistar rats [P15-25]. Seizure activity was induced by continuous perfusion of the slices with low-Mg2+ ACSF. Extra cellular recordings were performed in the hippocampal CA1 pyramidal cell layer. Seizure activity was quantified by measuring the amplitude and duration of the ictal events as well as their number after and prior to the application of the agonists and antagonists of the opioid receptors. In addition, the numbers of interictal spikes were determined to complement the analysis of seizure discharges before and after drug application. Our results show that DAMGO and Dyn-A [10 micro M], as micro and kappa-opioid receptor agonist respectively, cause a significant increase in the incidence and amplitude and duration of ictal activity and these effects were completely reversed following the appilcation of B-FNA and nor-BNI [10 micro M] as micro and kappa opioid receptor antagonist respectively. DPDPE [10 micro M], a selective delta-opioid receptor agonist, caused a significant decrease in the incidence and duration of ictal activity and these effects were completely reversed by the addition of NTI [10 micro M], a selective delta opioid receptor antagonist. Our finding showed that epileptic effects of morphine probably are established by activation of micro and kappa opioid receptors and due to the activation of delta opioid receptor, morphine produces antiepileptic effects

[Effects of Matricaria Chamomilla extract on morphine withdrawal syndrome in mice]

Matricaria chamomilla [MC] contains flavonoids, which exert benzodiazepine-like activity and so it may be helpful in morphine withdrawal syndrome [MWS] treatment. To determine the effects of MC extract on morphine withdrawal syndrome signs in adult male mice. This was an experimental study carried out in two steps at the department of physiology, Qazvin School of medicine [Iran], in 2005. Step 1: 3 adult male mice [n=6] were originally divided into 2 groups marked as saline [control] and morphine [case] groups. The morphine group were injected by increasing doses of morphine [10, 20, 40 mg/kg, s.c], 3 times daily, for a total duration of 4 days and were further divided into 4 subgroups as morphine group and 3 MC extract groups receiving one dose of MC extract [10, 20 or 30 mg/kg I.P] at day 4, 30 min before naloxone injection. At the end of training day [4[th] days] all groups were injected by naloxone [5mg/kg I.P] and MWS was studied for 30 minutes. Step 2: another 30 adult male mice [n=6] were injected by saline, morphine and MC extracts as above except for morphine and naloxane which were injected as one single dose [50 mg/kg]. Naloxone was injected 3hr after the last injection of morphine and the frequencies of withdrawal behaviors [jumping, climbing] were assessed later. The results of the present study showed that the acute and chronic administration of MC at doses used in our experiment significantly abolished the morphine withdrawal syndrome signs [jumping, climbing, writhing, weight loss] compared with morphine group. Our data suggest that the MC can attenuate the expression of withdrawal behaviors in male mice

[ effect of ascorbic acid on morphine withdrawal syndrome signs in rats]

Recent studies indicate that the glutamatergic and dopaminergic systems are also involved in morphine withdrawal syndrome. Ascorbic acid [AA] released from glutamatergic neurons, modulates the synaptic action of dopamine and glutamate as well as behavior. To determine the effects of ascorbic acid on morphine withdrawal syndrome signs [MWS]. 30 Male rats [250-300gr] were tested in 5 groups as: 1] control group [n=6] received 3% sucrose in tap water; 2] dependent group received morphine [0.1, 0.2, 0.3, 0.4mg/ml for a period of 48h, and 0.4mg/ml for further days up to 21st day] and 3% sucrose in tap water; 3,4,5] morphine-AA groups which received morphine and AA [100, 500, 1000mg/kg IP, every 48h] for evaluating the effects of AA on MWS. At the end of training period, all groups received naloxone [2mg/kg IP] and MWS were studied for 30 minute. Our results showed that IP application of AA [100, 500, 1000 mg/kg] can remarkably attenuate many signs [but not all] of morphine withdrawal syndrome, dose dependently. Based on data obtained in present study, AA can attenuate the expression of withdrawal behaviors in rats

[ effect of reversible locus coeruleus [LC] on i.v self-administration of morphine and morphine withdrawal syndrome[MWS] signs in rats]

Locus coeruleus [LC] has been hypothesized to play an important role in a variety of behaviors and opiate withdrawal. This study was designed to determine the effects of reversible inactivation of LC on self-administration of morphine and morphine- withdrawal syndrome signs [MWS]. 24 male rats [250-300gr] were surgically implanted bilaterally with cannula in LC then implanted with catheters in the right jugular vein. The rats were tested in 2 groups:Control[saline] and morphine. Morphine group was divided into 3 subgroups: control, sham-operated and LC-inactivated group where they received 1microL 2% Lidocaine 5 minutes prior to testing. Animals were allowed to self-administer morphine [1mg/infusion] during 10 consecutive days for 2 hours. The number of lever pressing was recorded. At the end of the training day all groups received naloxone [2mg/kg I.P] and MWS were studied for 30 minutes. LC inactivation prevents the development of tolerance and dependence on morphine and greatly attenuates morphine-withdrawal syndrome. LC inactivation not only attenuates morphine withdrawal syndrome but also prevents morphine tolerance and dependence in rats

[Matricaria chamomilla extract infusion in to nucleus paragigantocellularis attenuates most of morphine withdrawal syndrome signs in rats]

Some reports show that co-administration of Matricaria chamomilla [MC] extract with morphine, greatly attenuate the development of morphine dependence and inhibit the expression of abstinence syndrome in morphine-dependent animals. Locus Coeruleus [LC] and nucleus paragigantocellularis [PGi] play an important role in developing symptoms of opiate withdrawal. The objective of this study was to determine the effects of Matricaria chamomilla extract infusion into PGi on morphine withdrawal syndrome signs [MWS] of rats. Thirty male rats [weight: 250-300gr] were surgically implanted with cannula at the PGi and then tested in 2groups: saline [control group] and morphine [twice daily for 7 days]. The dose of morphine on the first and second days was 2.5 mg/kg and was doubled every day. On 7[th] day, the animals received the last injection of morphine [50mg/kg] and divided in 4 subgroups: the morphine group [which only received morphine] and three MC groups [which received 1 micro l of MC extract with the concentrations of 10, 25, 50 micro g/micro l, 5 min before naloxone administration]. In the end of the training day [7[th] day] all groups were received naloxone [5mg/kg IP] 3h after last injection of morphine and then the frequencies of withdrawal behavior [jumping, climbing] were assessed for 30 minute. Our results showed that central administration of MC extract, especially at high doses [25 micro g/micro l], significantly attenuates most signs of the morphine withdrawal syndrome. These results suggest that the injection of MC extract into the PGi may be helpful for morphine withdrawal syndrome treatment

[Effects of Matricaria chamomilla extract injection into paragigantocellularis nucleus on morphine withdrawal signs in rats]

Reports suggest that co-administration of Matricaria Chamomilla [MC] extract with morphine greatly attenuates the dependence on morphine and its injection prior to naloxan inhibits the withdrawal syndrome. Locus Ceruleus [LC] and paragigantocellularis [PGi] nuclei play a key role in appearance of withdrawal syndrome. Thus, this study was conducted to determine the effects of MC extract injection into pGi nucleus on morphine withdrawal in rats. 30 rats [Weighing 250-300gr] were divided into two groups of control [receiving saline] and morphine-treated. Following surgical implantation of cannula, morphine-treated group received morphine twice daily for 7 days. This group was classified into 4 sub-groups.The first sub-group received only morphine while the three remaining sub-groups were administed with Matricaria Chamomilla on day 7, five minutes prior to 1 microliter naloxan injection, with 10, 25, and 50 micro gr/lit, respectively. In all groups 5 mg/kg naloxan was injected 3 hours after the final injection of morphine and withdrawal behavior [jumping and climbing] was investigated for 30 minutes. The results showed that injection of all three high doses of MC extract particulary 25 microgr/microlit into PGi nuclens could significantly decline the symptoms of withdrawal syndrome. It seems that injection of MC extract into PGi nucleus could be beneficial to the treatment of morphine withdrawal syndrome in rats