Effect of Pranidipine on Primphos-Induced Seizure in Mice

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American-Eurasian Journal of Toxicological Sciences 4 (1): 11-15, 2012 ISSN 2079-2050 IDOSI Publications, 2012 DOI: 10.5829/idosi.aejts.2012.4.1.56258 Effect of Pranidipine on Primphos-Induced Seizure in Mice Hatefi Farzam Young Researchers Club, Tabriz Branch, Islamic Azd University, Tabriz, Iran Abstract: Primphos a synthetic Organophosphorus compound used mainly as insecticides are the property of insecticide. These toxins can be used as insecticides in agriculture and medicine for animals and the destruction of ectoparasites. Studies have shown that Primphos creation seizure effects in different animals. Pranidipine, dihydropyridine calcium channel blockers, widely used for treatment of cardiovascular diseases. Studies have shown that the calcium channel blockers having anticonvulsant effects in different animal models. The aim of this study was to determine the effect of pranidipine on Primphos-induced seizures in mice. In this experiment, the animals were received different doses of pranidipine (2.5, 5, 10, 20 and 40 mg kg b. wt.) intraperitoneally, 30 min before intraperitoneal injection of Primphos (500 mg/kg b. wt.). After Primphos injection, clonic and tonic seizures and death was investigated. Results showed that pranidipine dose dependently reduced the severity of Primphos-induced seizures, so that pranidipine at a dose level of 5 mg/kg and 40 mg/kg, had the lowest (p<0.05) and highest (p<0.001) anticonvulsant effects, respectively. The anticonvulsant activity of pranidipine suggests that possibly due to antagonistic effect on voltage-dependent calcium channel. Key words: Pranidipine Primphos Seizures Mice INTRODUCTION Other investigators also reported that calcium channel in some models have anticonvulsant effects [1, 3, 7, 9, 10] Epilepsy is one of the major neurological diseases in but in all animal models of seizures has not demonstrated humans and about one percent of the population is these effects [10, 11]. Also in rats anticonvulsant effects involved. It has been shown that epileptic seizure occurs of calcium channel inhibitors shown but seizure agent has due to occasional discharges in nerve tissue. It is not Primphos. Some medications such as anticonvulsants recognized that occasional changes in reversible neuronal phenytoin and carbamazepine can induce their effects by function, causing brain electrical activity. In some cases, inhibiting sodium channels directly and indirectly by the seizure occurs due to the entry of calcium ions into preventing the flow of calcium from the membranes of nerve cells and reducing intracellular calcium neurons and reduction of excessive concentration of concentration in some epileptic animal models which has intracellular calcium. Specific drugs used to treat epilepsy inhibitory effect on seizures. During seizures increased are absence seizure kind of like channels as T-type intracellular calcium ion concentration while extra cellular calcium in thalamic neurons are blocked. This reduced calcium concentration decreases [1-6]. Calcium channel calcium ion concentration of the important goals in antagonists for the treatment of hypertension were development of neuroprotective and antiepileptic drugs produced in the year 1980. Use of these drugs over time [5, 6]. Calcium entry into neurons play an important role in to treat other diseases was developed, such as treatment creating the seizures and calcium channel inhibitors have of angina, supraventricular tachycardia attack, different effects on health, including cardiovascular hypertrophic cardiomyopathy, pulmonary hypertension diseases, migraine and headaches caused by vascular and migraine. Recently have shown that calcium channel changes, nerve regeneration and neuronal regenerative blockers may have anticonvulsant effects in some animal processes [4], So it seems calcium channel inhibitors used models. Calcium channel blockers inhibit calcium ion flow to treat seizures can be useful. Results of these studies for through L-type calcium channels sensitive to voltage the anticonvulsant effects of calcium channel inhibitors [1, 3, 7]. It has been shown that calcium channel inhibitors suggests, therefore likely to pranidipine reduce Primphosin models of nerve tissue in a large protective effect [3, 8]. induced seizures. Since no research based on the Corresponding Author: Hatefi Farzam, Young Researchers Club, Tabriz Branch, Islamic Azad University, Tabriz, Iran. Tel: +98-914-491-0458. 11

combined effect of these seizures from Primphos there, in administered intraperitoneally with constant volume and this case study seems necessary. Insecticide use in by weight per animal. To remove the effect of injection agriculture and veterinary medicine as strange since volume on seizures, all drugs and Twin 80, at 10 ml/kg was World War II and grew during the past 20 years has set. First, seizures was assessed in animals receiving reached its highest rate constant. While the main Primphos and then evaluated the effect of Twin 80 on consumers of agricultural insecticide industry is also large Primphos-induced seizures with the above injection, 30 quantities of other industries use them and their minutes before the seizure was determined. More applications in and around homes is considerable. Most experimental animals, different doses of pranidipine of insecticide residues on the remaining products and (2.5, 5, 10, 20 and 40 mg/kg) received 30 min before the people exposed to low doses of chemicals through the intraperitoneal injection of Primphos. To create seizures, foods. Numerous incidents of acute insecticide poisoning mice received Primphos (500 mg/kg B.W.) intraperitoneally caused by eating food that mainly followed during and then the animals treated for 120 minutes were storage or transportation had been infected was created recorded by video camera. Films from the following four [1, 2, 13]. Including the insecticide, which are potential behaviors were recorded: starting time of clonic seizures toxicity, are organophosphate. One of the after injection of Primphos (second), Generation time of organophosphate is Primphos. The aim of this study was death after Primphos injection (second), mortality after to determine the effect of pranidipine (calcium channel injection of Primphos (persentage) and type of seizures antagonist) on Primphos-induced seizures. induced by injection of Primphos (percentage). After testing data as the mean±sem expression and to analyze MATERIALS AND METHODS data, ANOVA followed by Tukey multiple comparison tests were used. Value of p<0.05 to determine significance Male mice NMRI, weighing between 25-30 grams, between groups was considered. were purchased and maintained in laboratory of animal breeding center of Tabriz Islamic Azad University and RESULTS were kept at room temperature, light and humidity constant. Animals access to food and water were freely. Effect of Twin 80 as solvent, on Primphos-induced All tests were performed between 10-16 hours. Primphos seizures showed that this substance has no significant and pranidipine, both were solved in Twin 80 (5%). effect on seizures. Therefore the results had not presented Animals were divided randomly and placed in treatment in graphs and tables have been avoided. Effect of groups (each group n=10). Pranidipine and Twin 80 were different doses of pranidipine (2.5, 5, 10, 20 and 40 mg /kg Graph 1: Effect of different doses of pranidipine on the starting time of clonic seizures after injection of Primphos (second). mean±sem any form of graphs are presented. * P<0.05, ** P<0.01 and *** P<0.001 compared with Primphos group 12

Graph. 2: Effect of different doses of pranidipine on Generation time of death after Primphos injection (second). mean±sem any form of graphs are presented. * P<0.05 and *** P<0.001 compared with Primphos group Graph. 3: Effect of different doses of pranidipine on the mortality after injection of Primphos (percentage) b. wt.) on Primphos-induced seizures showed that this became more severe and cause death. In this study, drug dose-dependently reduced the Primphos-induced pranidipine dose dependently reduced clonic and tonic seizures (Graphs 1 and 2) Most anticonvulsant effect of seizures and deaths from Primphos. The results showed pranidipine on the mortality and severity of seizures with that the results of different researchers before treatment a dose of 40 mg/kg was observed (Table 1 and Graph 3). with calcium channel antagonists, seizure activity creation of different materials down to is in agreement. If DISCUSSION pranidipine in preventing tonic convulsions caused by PTZ [4], Aminophyline [9] and pilocarpine [10] have a In this study, Primphos cause clonic and tonic protective effect, but unlike the above models in all tests seizures and ultimately death. After the mice received anticonvulsant effect has been observed. For example intraperitoneal Primphos, some degree of tremor and Kainic acid induced seizures, administration of nimodipine excessive activity showed that over time the symptoms before this material could not reduce seizures [7, 8]. 13

Table 1: Effect of different doses of pranidipine on the type of seizures induced by Primphos injection (percentage) Type of seizures (percentage) ----------------------------------------------- Group Low Moderate Severe Primphos 0 0 100 Pranidipine 2.5+primphos 0 0 100 Pranidipine 5+primphos 0 20 80 Pranidipine 10+primphos 20 40 40 Pranidipine 20+primphos 50 30 20 Pranidipine 40+primphos 60 30 10 In another study showed that calcium channel blockers with values above 80 mg/kg could inhibit tonic seizures from chemicals including PTZ in mice and rats [7, 11, 14], but later showed that high doses of calcium channels blockers cause systemic and cardiac disorders, such as a sharp reduction in coronary blood pressure, decreased movements, imbalance and headache relief [5, 6]. Epilepsy in patients who were resistant to treatment, have reported that nimodipine in an uncontrolled study, seizure frequency is reduced [7, 15], but in another study that two strains were unaware controls, no anticonvulsant effects was observed by nimodipine [16]. Other problems prescription drug, long term administration of drugs with low prescribed intervals (three to four times a day to several weeks) and side effects include headache and hypotension, pronounced the man was from animal models. However, after 24 and 72 hours of administration of nimodipine, percent of alpha and theta waves was increased and vice versa percent in delta waves electroencephalogram was reduced [6, 16]. Other studies have shown that the anticonvulsant effects of calcium channel blockers, with other ntiepileptic drugs, increases, For example, in mice and rats with concurrent administration of nimodipine with other drugs can be decreased PTZ-induced tonic seizures, seizures resulting from sound and relieve the electroshock [8, 11-12]. Dihydropyridine calcium channels blockers in experimental seizures by ischemia, bicuculine, electrical cortical shocks, nitrous oxide and alcohol withdrawal syndrome is caused due, have anticonvulsant effects [17]. In another study, calcium channel blockers such as verapamil, nifedipine and Flunarizine to prevent of penicillin-induced seizures and electroencephalogram range have changed [17]. Calcium channel inhibitors on seizures induced by N-methyl-D, L-aspartate (NMDLA) and dihydropyridine calcium channel agonist BAY K 8644 have been effective [5, 18]. In another study on rats have shown that nimodipine in animal models of seizures, nerve discharge from BAY K 8644 and reduced the decrease in spike-wave EEG [7, 5]. Also have shown that this drug is ischemic brain damage has protective effects [17]. These studies suggest that protective effects of calcium channel antagonists probably due to blocking L-type calcium channels during seizures. These drugs inhibit voltagedependent calcium channels in seizures, the increase in intracellular calcium to prevent. Well marked that increased Ca2+ into the cell in the incidence of certain types of seizures plays a role [4], also marked the loss of calcium outside the cell with reduced flow of calcium from the membranes of neurons for several seconds the discharge of neurons that causes seizures be prevented and the threshold increases [19]. Some of the other antiepileptic drugs such as phenytoin and carbamazepine with a direct effect on neuronal sodium channels act directly or indirectly the flow of calcium ions from the membranes of neurons are inhibited [5, 6]. So it is likely that dihydropyridine calcium channel antagonists to act with similar mechanisms. Also have shown that pranidipine may inhibit calcium, sodium, chloride and potassium and calcium dependent glutamate channels [5]. CONCLUSION In summary, this study showed that pranidipine (voltage-dependent calcium channel antagonist type L) decreased clonic and tonic seizures from Primphos in mice are probably the main mechanism anticonvulsant related to block calcium channels and reduce calcium flow within neurons. Of course, that this could be generalized to humans rather than question and anticonvulsant effects of dihydropyridine calcium channel antagonists in humans, further investigation is needed. REFERENCES 1. Khayatnouri, M., F. Hatefi and P. Iagmaie, 2011. Effect of Nifedipine on Primphos-Induced Seizure in Mice. Global Veterinaria, 6(6): 551-555. 2. Mohebbi, G.H., A. Jahangiri and P. Hajeb, 2011. Inhibition of Acetyl Cholinesterase Activity Farmers Exposed to Organophosphat Pesticides in Bushehr, Iran. American-Eurasian J. Toxicological Sci., 3(3): 127-129. 3. Khayatnouri, M., P. Iagmaie and F. Hatefi, 2011. Effect of Diltiazem on Primphos-Induced Seizure in Mice. American-Eurasian J. Toxicological Sci., 3(3): 115-119. 14

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