To investigate the effect of crocin on the progression and generalized seizure of temporal lobe epilepsy in mice.Hippocampus rapid kindling model was established in C57BL/6J mice. The effects of crocin on seizure stage, afterdischarge duration (ADD), number of stimulation in each stage and final state, the incidence of generalized seizure (GS), average seizure stage and ADD were observed.Crocin (20 mg/kg) significantly retarded behavioral seizure stages (<0.05) and shortened cumulative ADD (<0.01) during hippocampus rapid kindling acquisition in mice compared with vehicle group. Meanwhile, number of stimulations in stage 1-2 was significantly increased (<0.05) and the incidence of fully kindled animals was significantly decreased (<0.01). However, 10 or 50 mg/kg crocin showed no significant effect on the above indexes (all>0.05). Crocin (100 or 200 mg/kg) significantly decreased the incidence of GS (all<0.01) and reduced average seizure stages (all<0.01) in fully-kindled mice compared with vehicle group; Fifty mg/kg crocin only reduced average seizure stages (<0.05).Low-dose crocin can retard the progression in hippocampus rapid kindling acquisition in mice, while high-dose crocin relieves the GS in fully-kindled mice, which suggests that crocin may be a potential anti-epileptic compound.
Animals ; Anticonvulsants ; pharmacology ; Carotenoids ; pharmacology ; therapeutic use ; Dose-Response Relationship, Drug ; Electric Stimulation ; Epilepsy, Temporal Lobe ; chemically induced ; drug therapy ; Hippocampus ; drug effects ; physiopathology ; Kindling, Neurologic ; drug effects ; physiology ; Mice ; Mice, Inbred C57BL ; Seizures ; classification ; drug therapy

To investigate the effects of neuronal histamine on spatial memory acquisition impairment in rats with pentylenetetrazole-kindling epilepsy, and to explore its mechanisms.A subconvulsive dose of pentylenetetrazole (35 mg/kg) was intraperitoneally injected in rats every 48 h to induce chemical kindling until fully kindled. Morris water maze was used to measure the spatial memory acquisition of the rats one week after fully pentylenetetrazole-kindled, and the histamine contents in different brain areas were measured spectrofluorometrically. Different dosages of hitidine (the precursor of histamine), pyrilamine (H1 receptor antagonist), and zolantidine (H2 receptor antagonist) were intraperitoneally injected, and their effects on spatial memory acquisition of the rats were observed.Compared with control group, escape latencies were significantly prolonged on Morris water maze training day 2 and day 3 in pentylenetetrazole-kindling epilepsy rats (all<0.05); and the histamine contents in hippocampus, thalamus and hypothalamus were decreased significantly (all<0.05). Escape latencies were markedly shortened on day 3 by intraperitoneally injected with histidine 500 mg/kg, and on day 2 and day 3 by intraperitoneally injected with histidine 1000 mg/kg in pentylenetetrazole-kindling epilepsy rats (all<0.05). The protection of histidine was reversed by zolantidine (10 and 20 mg/kg), but not by pyrilamine.Neuronal histamine can improve the spatial memory acquisition impairment in rats with pentylenetetrazole-kindling epilepsy, and the activation of H2 receptors is possibly involved in the protective effects of histamine.
Animals ; Benzothiazoles ; pharmacology ; Brain Chemistry ; drug effects ; Epilepsy ; chemically induced ; complications ; Hippocampus ; chemistry ; Histamine H1 Antagonists ; pharmacology ; Histamine H2 Antagonists ; pharmacology ; Histidine ; pharmacology ; Hypothalamus ; chemistry ; Kindling, Neurologic ; physiology ; Memory Disorders ; drug therapy ; etiology ; Pentylenetetrazole ; Phenoxypropanolamines ; pharmacology ; Piperidines ; pharmacology ; Pyrilamine ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Receptors, Histamine H2 ; drug effects ; physiology ; Spatial Memory ; drug effects ; Spectrometry, Fluorescence ; Thalamus ; chemistry

OBJECTIVETo investigate the antiepileptic effects of various stimulation modes of low-frequency stimulation(LFS) on the kindling rats.

METHODSStimulating electrodes were implanted in the amygdala and current with constant intensity was applied to evoke kindling-induced seizures. The antiepileptic effect of LFS by open loop stimulation(before kindling), closed loop stimulation(immediately after kindling) and different forms of closed loop stimulation(whole stage after kindling and early stage after kindling) were investigated in amygdala kindled rats.

RESULTSThe closed loop LFS of whole stage after kindling can significantly inhibited seizure stages(P<0.01) and reduced afterdischarge duration(P<0.05). The closed loop LFS of early stage after kindling can significantly suppress the seizure stages, mainly in stages 0-3(P<0.05 or P<0.01). The open loop low-frequency stimulation did not inhibit the seizure stage during kindling acquisition(P>0.05).

CONCLUSIONThe antiepileptic effect of low frequency stimulation may have a mode-dependent effect. It may be helpful for the deep brain stimulation as a promising approach applied to clinical antiepileptic therapy in the future.

Amygdala ; Animals ; Deep Brain Stimulation ; Kindling, Neurologic ; Rats ; Seizures ; therapy

OBJECTIVETo investigate whether the waveform of electrical stimulus affects the antiepileptic effect of focal low-frequency stimulation (LFS).

METHODSThe antiepileptic effects of the LFS in sine, monophase square and biphase square waves were investigated in hippocampal kindled mice, respectively.

RESULTSCompared to the control group, sine wave focal LFS (30 s) inhibited seizure stages (2.85 ± 0.27 vs 4.75 ± 0.12, P<0.05), lowered incidence of generalized seizures (53.6% vs 96.5%, P<0.01) and reduced afterdischarge durations [(16.2 2 ± 1.69)s vs (30.29 ± 1.12)s, P<0.01] in hippocampal kindled mice, while monophase or biphase square wave LFS (30 s) showed no antiepileptic effect. Monophase square LFS (15 min) inhibited seizure stages (3.58 ± 0.16, P<0.05) and incidence of generalized seizures (66.7%,P<0.01), but had weaker inhibitory effect on hippocampal afterdischarge durations than sine wave LFS. In addition, pre-treatment and 3 s but not 10 s post-treatment with sine wave LFS resulted in suppression of evoked seizures (P<0.05 or P<0.01).

CONCLUSIONThe antiepileptic effect of LFS is dependent on its waveform. Sine wave may be optimal for closed-loop LFS treatment of epilepsy.

Animals ; Anticonvulsants ; Electric Stimulation ; Epilepsy ; Hippocampus ; physiopathology ; Kindling, Neurologic ; Mice ; Seizures ; physiopathology

Synaptic vesicle protein 2A (SV2A) involvement has been reported in the animal models of epilepsy and in human intractable epilepsy. The difference between pharmacosensitive epilepsy and pharmacoresistant epilepsy remains poorly understood. The present study aimed to observe the hippocampus SV2A protein expression in amygdale-kindling pharmacoresistant epileptic rats. The pharmacosensitive epileptic rats served as control. Amygdaloid-kindling model of epilepsy was established in 100 healthy adult male Sprague-Dawley rats. The kindled rat model of epilepsy was used to select pharmacoresistance by testing their seizure response to phenytoin and phenobarbital. The selected pharmacoresistant rats were assigned to a pharmacoresistant epileptic group (PRE group). Another 12 pharmacosensitive epileptic rats (PSE group) served as control. Immunohistochemistry, real-time PCR and Western blotting were used to determine SV2A expression in the hippocampus tissue samples from both the PRE and the PSE rats. Immunohistochemistry staining showed that SV2A was mainly accumulated in the cytoplasm of the neurons, as well as along their dendrites throughout all subfields of the hippocampus. Immunoreactive staining level of SV2A-positive cells was 0.483 ± 0.304 in the PRE group and 0.866 ± 0.090 in the PSE group (P < 0.05). Real-time PCR analysis demonstrated that 2(-ΔΔCt) value of SV2A mRNA was 0.30 ± 0.43 in the PRE group and 0.76 ± 0.18 in the PSE group (P < 0.05). Western blotting analysis obtained the similar findings (0.27 ± 0.21 versus 1.12 ± 0.21, P < 0.05). PRE rats displayed a significant decrease of SV2A in the brain. SV2A may be associated with the pathogenesis of intractable epilepsy of the amygdaloid-kindling rats.
Amygdala ; drug effects ; metabolism ; physiopathology ; Animals ; Anticonvulsants ; pharmacology ; Disease Models, Animal ; Drug Resistance ; Electric Stimulation ; Epilepsy ; drug therapy ; genetics ; metabolism ; pathology ; Gene Expression Regulation ; Hippocampus ; drug effects ; metabolism ; physiopathology ; Kindling, Neurologic ; drug effects ; genetics ; metabolism ; pathology ; Male ; Membrane Glycoproteins ; genetics ; metabolism ; Nerve Tissue Proteins ; genetics ; metabolism ; Phenobarbital ; pharmacology ; Phenytoin ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Synaptic Transmission ; Synaptic Vesicles ; drug effects ; metabolism ; pathology

BACKGROUNDHistamine H(3) receptor antagonists have been considered as potential drugs to treat central nervous system diseases. However, whether these drugs can inhibit epileptogenesis remains unclear. This study aimed to investigate the effects of thioperamide, a selective and potent histamine H(3) receptor antagonist, on the seizure development and memory impairment induced by pentylenetetrazole (PTZ)-kindling epilepsy in rats.

METHODSChemical kindling was elicited by repeated intraperitoneal (ip) injections of a subconvulsant dose of PTZ (35 mg/kg) once every 48 hours for 12 times, and seizure activity of kindling was recorded for 30 minutes. Control rats were ip injected with saline instead of PTZ. Morris water maze was used to evaluate the spatial memory. Phosphorylated cyclic adenosine monophosphate response element binding protein (p-CREB) was tested by Western blotting in hippocampus.

RESULTSIntracerebroventricular (icv) injections with thioperamide (10 µg, 20 µg) 30 minutes before every PTZ injections, significantly prolonged the onset of PTZ-kindling and inhibited the seizure stages. PTZ-kindling seizures led to the impairment of spatial memory in rats, and thioperamide ameliorated the impairment of spatial learning and memory. Compared to non-kindling rats, there was a significant decrease in p-CREB level in hippocampus of the PTZ-kindling rats, which was reversed by thioperamide.

CONCLUSIONSThioperamide plays a protective role in seizure development and cognitive impairment of PTZ-induced kindling in rats. The protection of thioperamide in cognitive impairment is possibly associated with the enhancement of CREB-dependent transcription.

Animals ; Anticonvulsants ; pharmacology ; Cyclic AMP Response Element-Binding Protein ; metabolism ; Histamine H3 Antagonists ; pharmacology ; Kindling, Neurologic ; drug effects ; Male ; Memory Disorders ; prevention & control ; Neuroprotective Agents ; pharmacology ; Pentylenetetrazole ; Piperidines ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Seizures ; prevention & control ; Synaptic Transmission

Animals ; Kindling, Neurologic ; drug effects ; Male ; Pentylenetetrazole ; toxicity ; Rats ; Rats, Wistar ; Skin ; innervation ; Sympathetic Nervous System ; physiology

OBJECTIVETo investigate and compare the effects of Compound Chaihu Shugan Decoction (CHSGD, "treatment from Gan") and Dingxian Pill (DXP, "treatment from the sputum") on the metabolism path of glutamate in the pentylenetetrazol-kindled seizure rats' hippocampus, thus exploring the molecular mechanism of "heterotherapy for homopathy".

METHODSA chronic kindling seizures rat model was established by intraperitoneal injecting pentylenetetrazol (PTZ). Totally 24 fully kindled seizure rats were randomized into four groups, i.e., the model control group, the Sodium Valproate (VPA) group, the DXP group, and the CHSGD group. They were respectively treated with normal saline, VPA, CHSGD, and DXP, respectively. Rats in the control group were treated with normal saline by peritoneal injection and by gastrogavage. After intragastric administration for 4 successive weeks, the glutamate (Glu) levels in the hippocampus were detected by high performance liquid chromatography (HPLC). The expressions of glutamate transporter-1 (GLT-1) proteins were detected by Western blot. The activity of glutamine synthetase (GS) was detected by using GS detection kit.

RESULTSCompared with the control group, the content of Glu in the model group significantly increased, and the expression of GLT-1 and the activity of GS significantly decreased (P < 0.01). Compared with the model group, the content of Glu in each medication group significantly decreased, and the protein expression of GLT-1 as well as the activity of GS significantly increased (P < 0.01). But when compared between the CHSGD group and the DXP group, the content of Glu was lower and the activity of GS was higher in the CHSGD group than in the DXP group (P < 0.01), while there was no statistical difference in the expression of GLT-1 between the two groups (P > 0.05).

CONCLUSIONSCHSGD ("treatment from Gan") and DXP ("treatment from the sputum") could both decrease the level of Glu and raise the expression of GLT-1 and the activity of GS, indicating that CHSGD and DXP both could regulate the metabolism path of Glu to affect the level of the Glu in the brain. But the effects of CHSGD were superior to those of DXP in decreasing the content of Glu and up-regulating the activity of GS, suggesting that there were some different effects targets between the two compounds on the metabolism path of Glu, which may be one of possible molecular mechanisms for treating epilepsy by heterotherapy for homopathy.

Animals ; Excitatory Amino Acid Transporter 2 ; metabolism ; Glutamic Acid ; metabolism ; Hippocampus ; metabolism ; Kindling, Neurologic ; Male ; Medicine, Chinese Traditional ; methods ; Pentylenetetrazole ; adverse effects ; Rats ; Rats, Wistar ; Seizures ; metabolism ; therapy

OBJECTIVETo investigate the effects of epileptogenesis and low frequency stimulation at epileptic focus on spontaneous neuropathic pain in rats.

METHODSBipolar stimulating electrodes were implanted in the amygdala and current with constant intensity was applied to evoke kindling-induced seizures. In partial and generalized stages of seizure acquisition, neuroma model of spontaneous neuropathic pain was prepared by completely transection of the left sciatic and saphenous nerves of rats. Autotomy behavior was scored daily until d 63 postoperatively. Rats were divided into 5 groups: Control (n=7), rats with partial seizures (1-3 stages, n=5), rats with generalized seizures (4-5 stages, n=7), rats with partial seizures and low frequency stimulation(n=4), rats with generalized seizures and low frequency stimulation(n=4). Low frequency stimulation was applied to the amygdala, the epileptic focus for 21 d from the d 2 after nerve transection.

RESULTSAutotomy level in rats with partial seizures was significantly lower than that in controls. The autotomy scores during postoperative d 40 ≊63 were significantly lower than those of controls, the area under the progression curve of autotomy behavior was decreased from 308.2 ±51.57 to 45.80 ±24.64, the onset day of autotomy was postponed by 32 d and none of the animals with partial seizures showed high autotomy, while 71.4 % of controls showed that on d 63 postoperatively. Rats with generalized seizures showed autotomy similar to controls, except that the onset day was postponed by 16 d. Autotomy behavior in rats receiving low frequency stimulation of the amygdala was not different from that in controls.

CONCLUSIONFocal seizures can lower sensitivity to spontaneous neuropathic pain in rats, while low frequency stimulation applied to the focus can abolish such effect.

Animals ; Disease Models, Animal ; Electric Stimulation ; adverse effects ; Epilepsy ; complications ; etiology ; Kindling, Neurologic ; Male ; Neuralgia ; etiology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the effects and mechanisms of Wuling mycelia on seizure development and learning ability induced by pentylenetetrazole-kindling epilepsy in rats.

METHODSSD rats were randomly divided into four groups: pentylenetetrazole-kindling model group (model group), low dose Wuling mycelia (0.3 g*kg(-1)) group (LD-WM group), high dose Wuling mycelia (0.6 g*kg(-1)) group (HD-WM group) and control group. The rats were intraperitoneal injected with a subconvulsive dose (35 mg*kg(-1)) of pentylenetetrazole (saline in control group) every 48 h for 12 times. Wuling mycelia was intragastrically applied 30 min before pentylenetetrazole injection. An 8-arm radial maze ( 4 arms baited) was used to measure the learning ability. Histamine was measured by chemical fluorometric enzyme immunoassay.

RESULTSCompared with the model group, the kindling stage of LD-WM group degraded significantly after 7th injection, the latency to the onset of myoclonic jerks (LTMJ) and the latency to the onset of generalized seizures (LTGS) prolonged after the 6th and 7th injection, respectively (P<0.05). The kindling stage of HD-WM group also degraded markedly after the 6th to 8th injection, and the LTMJ and the LTGS extended after the 8th to 9th and 6th injection, respectively (P<0.05). Compared with the control group, the frequency of working memory error (WME) and reference memory error (RME) of the model group in the 8-arm radial maze increased through 3-d training (P<0.05). The memory tests showed that the impairment induced by pentylenetetrazole was partially reversed by Wuling mycelia. Compared with the control group, brain histamine contents (hippocampus, cortex, thalamus and hypothalamus) were significantly lower in model group (P<0.05). But compared with the model group, hippocampal histamine contents in LD-WM group and hippocampal, thalamic and hypothalamic histamine contents in HD-WM group were elevated (P<0.05).

CONCLUSIONWuling mycelia can delay the kindling and ameliorate the ability of learning in rats with pentylenetetrazole-induced epilepsy and the enhancement of neuronal histamine activity may be one of possible mechanisms.

Animals ; Disease Models, Animal ; Drugs, Chinese Herbal ; therapeutic use ; Epilepsy ; chemically induced ; metabolism ; prevention & control ; Hippocampus ; metabolism ; Histamine ; metabolism ; Kindling, Neurologic ; drug effects ; Learning ; drug effects ; Male ; Pentylenetetrazole ; toxicity ; Rats ; Rats, Sprague-Dawley