Efekat neurotoksičnosti aluminijuma na elektrokortikalnu aktivnost mozga pacova

Abstract

The aim of our study was to investigate the electrophysiological effects of aluminium neurotoxicity. This animal model of neurodegenerative dementia was induced by chronic treatment of Wistarrats with aluminum chloride for 4 weeks - 2mg Al/kg, i.p, per day. Electrophysiological recordings of left and right somatosensory cortical areas of animals treated by aluminium and the control rats were done under Nembutal anesthesia. Analog to the digital one conversion of the recorded signals was performed at the sampling rate of 256 Hz. Spectral analysis of electrocortical activity during sequences of 120 s (divided in epochs of 8s) was obtained by Fast Fourier Transformation while fractal dimension (FD) of these signals was calculated by Higuchi's algorithm. The relative power spectra of cerebral activity were increased in delta frequency range and decreased in (8.1-32.0 Hz) range in aluminium treated animals compared to the controls. The average fractal dimension of electrocortical activity in aluminium treated animals was lower - 1.290 than the average fractal dimension of electrocortical activity in the control rats - 1.377. Spectral and fractal characteristics of brain activity could bean electrophysiological sign of developing neurodegenerative process similar to the Alzheimer's dementia.

Predmet ovog istraživanja je bio da se elektrofiziološki prouče efekti aluminijumske neurotoksičnosti. Animalni model neurodegenerativne demencije postignut je hroničnim tretmanom Wistar pacova sa aluminium hloridom u toku 4 nedelje u dozi od 2 mg/kg aluminijuma dnevno. Elektrofiziološko registrovanje levog i desnog somatosenzornog korteksa pacova tretiranih aluminijumom i kontrolnih pacova je vršeno pod Nembutalskom anestezijom. Analogno-digitalna konverzija registrovanih signala je izvršena pri frekvenciji semplovanja 256Hz. Spektralna analiza elektrokortikalne aktivnosti u trajanju od 120s (podeljena u epohe od 8s) je izvršena Furijeovom transformacijom, a fraktalna dimenzija ovih signala je izračunata Higučijevim algoritmom. Relativni spektri snage cerebralne aktivnosti u delta frekventnom opsegu su bili povećani, a u (8.1-15.0 Hz) frekventnom opsegu su bili smanjeni kod aluminijumom tretiranih životinja u odnosu na kontrolne. Srednja fraktalna dimenzija elektrokortikalne aktivnosti kod tretiranih pacova je manja - 1,290 u odnosu na srednju fraktalnu dimenziju elektrokortikalne aktivnosti kontrolnih pacova - 1,377. Spektralne i fraktalne karakteristike mogu biti elektrofiziološki znak razvitka neurodegenerativnih procesa kao kod Alchajmerove bolesti.