Pathology and pathophysiology of the amygdala in epileptogenesis and epilepsy

Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
Epilepsy Research (Impact Factor: 2.19). 03/2008; 78(2-3):102-16. DOI: 10.1016/j.eplepsyres.2007.11.011
Source: PubMed

ABSTRACT Acute brain insults, such as traumatic brain injury, status epilepticus, or stroke are common etiologies for the development of epilepsy, including temporal lobe epilepsy (TLE), which is often refractory to drug therapy. The mechanisms by which a brain injury can lead to epilepsy are poorly understood. It is well recognized that excessive glutamatergic activity plays a major role in the initial pathological and pathophysiological damage. This initial damage is followed by a latent period, during which there is no seizure activity, yet a number of pathophysiological and structural alterations are taking place in key brain regions, that culminate in the expression of epilepsy. The process by which affected/injured neurons that have survived the acute insult, along with well-preserved neurons are progressively forming hyperexcitable, epileptic neuronal networks has been termed epileptogenesis. Understanding the mechanisms of epileptogenesis is crucial for the development of therapeutic interventions that will prevent the manifestation of epilepsy after a brain injury, or reduce its severity. The amygdala, a temporal lobe structure that is most well known for its central role in emotional behavior, also plays a key role in epileptogenesis and epilepsy. In this article, we review the current knowledge on the pathology of the amygdala associated with epileptogenesis and/or epilepsy in TLE patients, and in animal models of TLE. In addition, because a derangement in the balance between glutamatergic and GABAergic synaptic transmission is a salient feature of hyperexcitable, epileptic neuronal circuits, we also review the information available on the role of the glutamatergic and GABAergic systems in epileptogenesis and epilepsy in the amygdala.


Available from: Brita Fritsch, May 08, 2015
  • Source
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Las psicosis de la epilepsia: presentación de un caso clínico y revisión de la literatura. The psychosis of epilepsy: a case report and literature review. Recibido: 13/08/2012; aceptado con modificaciones: 17/12/2012 RESUMEN: Presentamos el caso de un varón de 72 años con un diagnóstico previo de epilepsia del lóbu-lo temporal y esquizofrenia paranoide, que mostraba episodios de psicosis con sintomatología pleomórfica y atípica que no respondía bien al tratamiento anti-psicótico. El paciente no presentaba un deterioro en su personalidad y había demostrado un buen ajuste y funcionamiento social. Tras revisar el caso se llega a cuestionar el diagnóstico previo de esquizofrenia paranoide proponiendo el diagnóstico alternativo de epilepsia del lóbulo temporal: crisis comiciales con sintomatología psicótica. Se instaura el tratamiento adecuado con éxito lo que permite el alta del paciente a su domicilio. Revisamos la literatura en la materia, concluyendo que las psicosis de la epilepsia han de tenerse en cuenta en casos de psicosis atípicas, resis-tentes a tratamiento en personas con buen funciona-miento psico-social sin deterioro en su personalidad. PALABRAS CLAVE: epilepsia del lóbulo temporal; psicosis comiciales; psicosis de la epilepsia; psicosis de la epilepsia tipo esquizofrenia. CONFLICTO DE INTERESES: Ninguno. ABSTRACT: We describe the case of a 72 year old man with a diagnosis of temporal lobe epi-lepsy and paranoid schizophrenia, who presented atypical psychotic episodes which did not res-pond to anti-psychotic medication. His personali-ty had not deteriorated and he showed good social adjustment and functioning. After reviewing the case, we challenged the diagnosis of paranoid schizophrenia, proposing an alternative diagno-sis of temporal lobe epilepsy with ictal psycho-sis. He was successfully treated and discharged home. We review the literature on the subject. The psychosis of epilepsy are a diagnostic option which must be seriously considered in cases of treatment resistant atypical psychosis in subjects with good pre-morbid functioning and social ad-justment free from personality decline. KEY WORDS: temporal lobe epilepsy; ictal psychosis; psychosis of epilepsy; schizophrenia like psychosis of epilepsy. DECLARATION OF INTEREST: None.
    01/2013; 33(118):123-134. DOI:10.4321/S0211-57352013000200010
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Epilepsy is a mystery even though it affects an estimated 50 million people worldwide. Its management is enigmatic and as such, is not curative, but rather aims to attain freedom from seizures without side-effects. However, an approach for the selection of the most effective drugs and doses for individual patients is lacking. Almost all of the antiepileptic drugs in current use are associated with adverse reactions, some of which are severe and life-threatening. A more comprehensive treatment strategy requires improved research on epilepsy. This is the key to developing a treatment plan focused on the individual needs of each patient. Pharmacogenetics can offer a novel line of attack in the treatment of epilepsy. The potential advantages of gene therapy in the management of epilepsy are manifold. It encompasses the principle of testing as to how genetic variation among individuals affects variation in drug response, efficacy, and potential adverse drug events. Pharmacogenomics is the investigation of relationships between patient genotype and responses to drug treatment. It holds the promise of selecting the right drug at the right dose for the right person. A conceptual framework that outlines the pharmacogenetic and pharmacogenomic aspects of epilepsy presented here. Future directions for research and the application of these technologies to the clinical practice of individualising treatment for epilepsy are also discussed. A combination of research strategies and prudent policies from government may lead to a better understanding of treatment effects and futuristic but realistic management in epilepsy.