Neurogenesis in the amygdala: a new etiologic hypothesis of autism?
Neurogenesis studies had an increased development after BrdU (5-bromo-3'-deoxyuridine), a marker of cell proliferation. Today, several studies have showed the relevance of neurogenesis in the hippocampal formation. Notwithstanding, other brains areas have been described presenting neurogenesis, including the amygdala. This key structure is a complex cerebral region which has been associated with social behaviors and the emotional significance of the daily experiences. Several studies have associated the amygdala to the autism, a severe neurodevelopmental disorder. In this paper, we discuss the hypothesis of neurogenesis in the amygdala as a contributing cause of autism. The social skills require competent new neuronal connections, including efficient plasticity synaptic rearranging. Interestingly, emotional context cannot be imprinting in mature neurons in the presence of GABA, a neurotransmitter release during new environments experiences. However, it is known that new neurons are not well responsive to GABA stimulation, allowing the long-term potentiation necessary for the learning process. Based on these evidence it is tantalizing to hypothesize that the sociability impairment seen in some individuals with autism may partly be assigned to impaired regulation of the GABAergic system and to the impact of this impairment on the adequate functioning of the amygdala and on its capacity to store new experiences and to modulate the plasticity of the corticostriatal connections.
Mercadante
Marcos Tomanik
MT
Department of Psychiatry, Universidade Federal de São Paulo/Escola Paulista de Medicina, São Paulo, Brazil.
Cysneiros
Roberta Monterazzo
RM
Schwartzman
José Salomão
JS
Arida
Ricardo Mario
RM
Cavalheiro
Esper Abrão
EA
Scorza
Fulvio Alexandre
FA
D000679:Amygdala / Q000254:growth & development / Q000473:pathology / Q000503:physiopathology*; D000818:Animals; D001321:Autistic Disorder / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology / Q000523:psychology; D006801:Humans; D008959:Models, Neurological; D009473:Neuronal Plasticity; D012919:Social Behavior; D005680:gamma-Aminobutyric Acid / Q000502:physiology
D005680:gamma-Aminobutyric Acid