Author(s)

Marta López-Santibáñez Guevara, Eileen Uribe-Querol, Alma Lilia Fuentes Farías, Esperanza Meléndez-Herrera, Agustine Joseph D’Ercole, Gabriel Gutiérrez-Ospina

Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México D.F., México.
Departamento de Zoología, Instituto de Investigaciones sobre los Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, México.
Department of Pediatrics, The University of North Carolina at Chapel Hill, Chapel Hill, USA.
División de Estudios de Posgrado e Investigación, Facultad de Odontología, Universidad Nacional Autónoma de México, México D.F., México.

Circuits in barrels of the rodent brain’s primary somatosensory (S1) cortex build up following constructivist rules. Previous evidence in mice supports that the precise addition of barrel neuropil is promoted by insulin-like growth factor-1 (IGF-1). The signaling cascades mediating this response remain undetermined. To address whether the effects of IGF-1 upon the growth of S1 circuits are mediated by insulin receptor substrate-1 (IRS-1), we studied barrel size in adult mice having the IRS-1 gene knocked out (IRS-1 ko). Our results reveal that barrel size is similar between wild type and IRS-1 ko mice suggesting that IRS-1 is not essential for barrel circuitry growth. Hence, investigations aimed at exploring other substrates activated by IGF-1, namely IRS-2 and IRS-4, are needed to reveal signaling pathways that mediate the precise addition of S1 neuronal circuitry. 

Barrel Cortex; Neuronal Circuit Assemblage; Trophic Interactions; Constructivism

Guevara, M. , Uribe-Querol, E. , Fuentes Farías, A. , Meléndez-Herrera, E. , D’Ercole, A. and Gutiérrez-Ospina, G. (2013) Cortical columns (barrels) display normal size in the brain’s primary somatosensory cortex of mice carrying null mutations of the insulin receptor substrate 1 gene: A preliminary report. Advances in Bioscience and Biotechnology, 4, 945-948. doi: 10.4236/abb.2013.410125.