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Arousal deficit shown in aged rat's quantitative EEG and ameliorative action of pramiracetam compared to piracetam

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Abstract

The basal EEG profile of the aged Fisher-344 rat was consistently different from that of the young rat, showing dominant high voltage slow-wave components. These slow waves were present in both the frontal cerebral cortex and dorsal hippocampus. Absent or greatly attenuated in the aged rat's hippocampal EEG was rhythmic theta activity, which was always dominant in the young awake rat's hippocampus. These EEG differences were clearly apparent only under basal test conditions, i.e., following habituation to the test situation. Pramiracetam sulfate acted strongly to normalize the aged rat's EEG, while the action of piracetam was weak and appeared to undergo tolerance development.

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... Прамирацетам способствовал нормализации ЭЭГ у старых крыс. На фоне его применения повышалась частота высоковольтажных медленных волн, ослабленных или отсутствующих у старых животных [499,500]. ...
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Монография посвящена анализу методов синтеза и биологической активности рацетамов - структурных аналогов ноотропного препарата пирацетама. В книге систематизированы литературные данные и результаты собственных исследований по методам синтеза и фармакологическим свойствам наиболее известных рацетамов, содержащих пирролидоновый цикл. В первой главе представлены сведения о способах получения рацетамов, применяемых в медицинской практике или находящихся на разных стадиях разработки, а также о свойствах и строении со-кристаллических форм рацетамов с различными органическими кислотами и неорганическими солями. Вторая глава содержит анализ фармакологических свойств рацетамов, используемых в медицине или изучаемых в качестве биологически активных субстанций. Книга предназначена для преподавателей, научных сотрудников, аспирантов, студентов магистратуры и бакалавриата, работающих в области органической, медицинской химии и фармакологии.
... In humans, EEG slowing is related with cognitive impairment secondary to neurological disorders ( Leocani et al., 2000Leocani et al., , 2010 or, even in healthy subjects, with lower scores of working memory (Klimesch, 1997), IQ (Klimesch, 1999) or with drug-induced drowsiness and cognitive impairment (Salinsky et al., 2004). In rodents, background EEG slowing and reduced thetaealpha power are nonspecific events, often associated with physiological or druginduced vigilance deficits (Parmentier et al., 2002), learning impairment ( Colas et al., 2005), aging ( Poschel et al., 1985) or pathological conditions, such as traumatic brain injury (Fedor et al., 2010). In addition, a direct effect of drug treatment on EEG and behaviour has been reported (Pálení cek et al., 2012;Krijzer et al., 1993). ...
... In rodents, background EEG slowing and reduced theta-alpha power are non specific findings, usually associated with physiological or drug-induced vigilance deficit. Those are generally considered as a landmark of learning impairment after administration of anticholinergic drugs (Vanderwolf, 1991), aging (Poschel et al., 1985 ) or pathological conditions, such as traumatic brain injury (Fedor et al., 2010). In the present study, the lack of continuous monitoring does not allow to determine whether EEG background slowing precedes or follows the first ever seizure in these mice. ...
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