6/15/2023 0 Comments Hypoxia memory note book![]() Using drugs to block the activity of an enzyme called cyclooxygenase-2 or other proteins called L-type calcium channels prevented both the oxygen shortage and the behavioural impairments that follow seizures. The experiments show that after an epileptic seizure, blood vessels become narrower, which reduces blood supply to the areas of the brain involved in the seizure and dramatically reduces oxygen levels in those same areas. studied blood flow in the brains of mice, rats and human volunteers with epilepsy. Following a seizure, is there a local stroke-like event that is responsible for the behavioural and memory impairments? It has been observed that the impairments that follow seizures are similar to those that follow strokes, where for a period of time blood flow to certain areas of the brain is restricted and these areas are starved of oxygen. While these events reduce quality of life in people with epilepsy, they have gone untreated because we did not understand what occurs in the brain after seizures. Likewise, amnesia may follow a seizure that affects brain areas involved in memory. Because the brain is organized so that specific tasks happen in particular areas, seizures that affect areas of the brain that control movement are often followed by muscle weakness. It has long been known that after an epileptic seizure, individuals often experience an extended period of impairments that affect how the brain works. Thus, epilepsy is much more than a disease hallmarked by seizures, since the occurrence of postictal hypoperfusion/hypoxia results in a separate set of neurological consequences that are currently not being treated and are preventable. Using inhibitors of these targets we separated the seizure from the resulting severe hypoxia and show that structure specific postictal memory and behavioral impairments are the consequence of this severe hypoperfusion/hypoxic event. This event lasted over an hour, is mediated by hypoperfusion, generalizes to people with epilepsy, and is attenuated by inhibiting cyclooxygenase-2 or L-type calcium channels. We measured brain oxygenation in localized areas from freely-moving rodents and discovered a severe hypoxic event (pO 2 < 10 mmHg) after the termination of seizures. Here we show that seizures result in a severe hypoxic attack confined to the postictal period. Seizures are often followed by sensory, cognitive or motor impairments during the postictal phase that show striking similarity to transient hypoxic/ischemic attacks.
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