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Background: There is no universally accepted behavioral scoring to define the early development of pentylenetetrazole (PTZ) kindling. Therefore, studies investigating alterations of neurogenesis in the PTZ model were mainly focused on full kindled animals rather than early stages of kindling. This study aimed to determine an appropriate behavioral index for categorizing stages of PTZ kindling progress and to evaluate neurogenesis during PTZ kindling., Materials and Methods: Twenty-four mice were intraperitoneally injected with a sub-convulsive dose of PTZ (40mg/kg) every other day until they became full kindled. The first occurrence of different seizure behaviors and their durations were recorded during kindling development, and the different stages of kindling were categorized. Neurogenesis was evaluated in the lateral subventricular zone (SVZ) at each stage of kindling by immunofluorescence staining., Results: First occurrence of restlessness, motionless staring, hind limb tonic extension, Straub's tail, myoclonic jerk, and tonic-clonic were sequentially observed in more than 80% of animals with increasing PTZ injections. The duration of the myoclonic jerk was significantly longer than the other seizure behaviors. The significantly higher percentage of BrdU-positive cells was found in SVZ of mice showing tonic-clonic in comparison to other seizure behaviors., Conclusion: A hierarchy behavior was observed during the kindling process when considering the first occurrence of seizure behaviors. We defined the first occurrence of restlessness, motionless, hind limb tonic extension and Straub's tail behaviors as an early phase, myoclonic jerk as a borderline phase and tonic-clonic as a late phase of PTZ-induced kindling. Our results indicated an enhanced SVZ neurogenesis at the late phase of kindling., (Copyright© 2019, Galen Medical Journal.)

Background: Treatment of Alzheimer as a disease that is associated with cognitive impairment has been associated with some restrictions. Recently, researchers have focused on non-pharmacological treatments, including non-invasive stimulation of the brain by transcranial electrical stimulation (tES). Four main paradigms of transcranial electrical current include transcranial direct current stimulation (tDCS), transcranial alternative current stimulation (tACS), transcranial random noise stimulation (tRNS), transcranial pulse current stimulation (tPCS). The tDCS is a possible new therapeutic option for patients with cognitive impairment, including Alzheimer disease., Materials and Methods: The study was done on Sprague-Dawley male rats weighing 250-270 g. to develop Alzheimer's model, the cannula was implanted bilaterally into the hippocampus. Aβ 25-35 (5μg/ 2.5µl/day) was microinjected bilaterally for 4 days. Then, an electrical stimulation paradigm was applied to the animal for 6 days. Animal cognitive capacity was evaluated on day 11 and 12 by novel object recognition (NOR) test., Results: Our results showed that application of tDCS; tACS; tRNS and tPCS reversed beta-amyloid-induced impairment (P<0.05). The tRNS Group spent total exploration time around the objects compared to other groups (P<0.05). There was no significant difference between the four different paradigms in discrimination ratio and the percentage of total exploration time., Conclusion: The results of this study showed that the use of multiple sessions of different tES paradigms could improve Aβ-induced memory impairment in the NOR test. Therefore, based on evidence, it can be expected that in addition to using tDCS, other stimulatory paradigms may also be considered in the treatment of AD., (Copyright© 2019, Galen Medical Journal.)