Susceptibility of different cortical areas to generate spike and wave discharges : an in virto study

• Main Author: Rigas, Pavlos
• Format: Others
• Language: en
• Published: McGill University 2003
• Subjects: Biology - Neuroscience
• Online Access: http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19427

During sleep and anesthesia the normal cortex displays slow-wave oscillations. Application of GABA-A receptor antagonists, such as bicuculline (BMI), both in vivo and in vitro transforms these slow oscillations into spike-wave discharges (SWDs). We studied if some areas of the cerebral cortex have a stronger propensity to generate SWDs and trigger SWDs in other less prone areas. Ten sequential mouse brain slices were prepared and named after 1-10 from posterior to frontal. During application of BMI spontaneous SWDs were observed in all slices and cortical sites. Interestingly, SWDs recurred at different frequencies in different slices; posterior slices (1-6) had a higher rate than the frontal slices (7-10) (~0.2 vs 0.1 Hz, posterior vs frontal). Investigating the origin of this discrepancy we found that neocortices are not primarily different. Instead, intrinsic differences along the posterior-frontal axis of the piriform cortex are what secondarily differentiate posterior and frontal slices.