Epilepsy is a chronic noncommunicable disease of the brain that affects people of all ages and causes frequent seizures. It is one of the most common neurological diseases globally, with around 50 million people worldwide having it.
In epilepsy, the electrical signals in the brain become scrambled and there are sometimes sudden bursts of electrical activity, which causes seizures. The causes of epilepsy are still unclear, but it is possible it could be partly caused by you genes or damage to the brain such as stroke and brain tumour.
Seizures caused by epilepsy can occur at any time, usually lasting from a few seconds to a few minutes. It can affect people in different ways and gives different symptoms and manifestations of seizures, depending on the location of seizure onset and propagation, and can be classified as focal (begins on one side of the brain) and generalised seizures (involve both sides of the brain).
Possible symptoms of epilepsy includes:
- Uncontrollable jerking and shaking, called a “fit”
- Losing awareness and staring blankly into space
- Becoming stiff
- Strange sensations, such as a “rising” feeling in the tummy, unusual smells or tastes, and a tingling feeling in your arms or legs
- Collapsing
- Sometimes patients with epilepsy might pass out and not remember what happened.
Seizures can be controlled, and up to 70% of people living with epilepsy could become seizure-free with appropriate use of antiseizure medicines. And, around 25% of epilepsy cases are preventable. Sometimes, other methods such as surgeries may be used, and most cases are curable. Before doctors can prescribe medications to their patients, preclinical studies on drug screening are important to ensure the drug safety.
Animal Models for Epilepsy – PTZ Model
Pentylenetetrazol(PTZ), a GABA-A receptor antagonist, is used to create a common chemically-induces seizure model. The PTZ model are categorized as a model of generalized seizure.
PTZ induces all four behavioural phenomena: freezing, myoclonic twitches, clonic seizures, and tonic-clonic seizures. The PTZ-induced kindling model has become a widely applicable technique for studying seizure mechanisms and to investigate the pathophysiology of epilepsy. Also, the PTZ model is used to investigate neuronal damage after epileptic seizures.
Animal Models for Epilepsy – KA Model
Kainic acid (KA) is a potent glutamate analog that is used to induce neurodegeneration and model temporal lobe epilepsy(TLE) in rodents. The model presents with neuropathological and electroencephalographic features that are seen in patients with TLE.
KA reliably induces severe, prolonged seizures, which is convulsive status epilepticus. The kainic acid model is widely used in the study of epilepsy and is reliable model for understanding TLE.