Dopaminergic signaling in the developing retina.
Brain Res Rev
; 54(1): 181-8, 2007 Apr.
Article
em En
| MEDLINE
| ID: mdl-17292477
ABSTRACT
The role of dopamine in the retina has been studied for the last 30 years and there is now increasing evidence that dopamine is used as a developmental signal in the embryonic retina. Dopamine is the main catecholamine found in the retina of most species, being synthesized from the L-amino acid tyrosine. Its effects are mediated by G protein coupled receptors constituting the D(1) (D(1) and D(5)) and D(2) (D(2), D(3) and D(4)) receptor subfamilies that can be coupled to adenylyl cyclase in opposite manners. Dopamine-mediated cyclic AMP (cAMP) accumulation, via D(1)-like receptors, is observed very early during retina ontogeny, before synaptogenesis and, in some species, before the expression of tyrosine hydroxylase (TH), the enzyme that characterizes the neuronal dopaminergic phenotype. D(2)-like receptors appear in the tissue days after D(1)-like activity is detected. In the embryonic avian retina, before the tissue is capable of synthesizing its own dopamine via TH, dopamine synthesis is observed from L-DOPA supplied to the neuroretina from retina pigmented epithelium which results in dopaminergic communication in the embryonic tissue before TH expression. Müller cells, the main glia type found in the retina, seem to actively contribute to dopaminergic activity in the retinal tissue. Understanding the dopaminergic role during retina development may contribute to novel strategies approaching certain visual dysfunctions such as those found in ocular albinism.
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Base de dados:
MEDLINE
Assunto principal:
Retina
/
Transdução de Sinais
/
Dopamina
/
Neurônios
Limite:
Animals
Idioma:
En
Revista:
Brain Res Rev
Assunto da revista:
CEREBRO
Ano de publicação:
2007
Tipo de documento:
Article
País de afiliação:
Brasil