Expression of medium and heavy chain neurofilaments in the developing human auditory cortex.
Brain Struct Funct
; 217(2): 303-21, 2012 Apr.
Article
en En
| MEDLINE
| ID: mdl-21987049
ABSTRACT
Neurofilament medium (NF-M) and heavy (NF-H) chain proteins have been used as markers for maturity in the developing brain since their accumulation in axons leads to an increase in conduction velocity. Earlier studies have demonstrated immunoreactivity of neurofilaments in Layer I of the human auditory cortex at 22 gestation weeks (GW), whereas that in other layers developed between 1 and 12 postnatal years, suggesting a gradual increase in the processing of sounds. However, third trimester fetuses and infants are fairly sophisticated in their ability to discern different aspects of complex sounds. Given these contradictory findings, we decided to study the expression of neurofilaments in human auditory cortex between 15 GW and adulthood. We found that mRNA and protein for both NF-M and NF-H were present in the presumptive human auditory cortex in the second trimester and during the postnatal period (1 year--adulthood). Axons in all layers of the auditory cortex were immunoreactive for neurofilaments by 25 GW and the density of the neurofilament-rich plexus in the cortical wall became adult-like during the first postnatal year in humans (9 postnatal months). Our results suggest that in terms of neurofilament expression, axons within the preterm human auditory cortex may be more mature than previously thought.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Corteza Auditiva
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Envejecimiento
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Proteínas de Neurofilamentos
Límite:
Adult
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Child, preschool
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Female
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Humans
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Infant
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Male
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Middle aged
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Newborn
Idioma:
En
Revista:
Brain Struct Funct
Asunto de la revista:
CEREBRO
Año:
2012
Tipo del documento:
Article
País de afiliación:
India