Receptores GABAA (ácido -aminobutírico) y su relación con la dependencia al alcohol

Ingeniería y ciencia, ISSN 1794-9165, Nº. 1, 2005, pags. 77-96 01/2012;
Source: OAI

ABSTRACT El síndrome de dependencia al alcohol es una enfermedad multifactorial, ambiental, cultural, social y genética. Son innumerables las investigaciones que han intentado elu- cidar los posibles mecanismos neurobiológicos de este síndrome para entender los cambios fisiológicos y comportamentales del individuo, de tal manera que se puedan brindar alter- nativas farmacológicas que ayuden a controlar este tipo dependencia. Esta revisión describe el papel de la neurotransmisión involucrada en el síndrome de de- pendencia al alcohol, principalmente la relacionada con el glutamato, la dopamina, los opioides y en especial el ácido -aminobutírico (GABA), porque la activación del receptor GABAA (receptor canal de cloro) desencadena un efecto inhibitorio a nivel neuronal, y en individuos alcohólicos presenta hipofunción, la cual no le permite modular la recurrente excitación neuronal obteniendo como resultado un estado de desinhibición/hiperexcitación típico de alcohólicos. Por otra parte, los genes que codifican para las subunidades de los receptores GABAA ubicados en los cromosomas 4 y 15 han sido asociados con alcoholis- mo, al presentarse fuertes relaciones entre el desequilibrio de unión entre estos genes y el fenotipo de las ondas _ en los electroencefalogramas de los individuos con el síndrome de dependencia al alcohol y sus descendientes. De acuerdo a las investigaciones en el tema, finalmente proponemos las posibles vías y sus mecanismos de control implicados en el síndrome de dependencia al alcohol.

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