IHEM   20887
INSTITUTO DE HISTOLOGIA Y EMBRIOLOGIA DE MENDOZA DR. MARIO H. BURGOS
Unidad Ejecutora - UE
artículos
Título:
Purkinje cells express Angiotensin II AT2 receptors at different developmental stages
Autor/es:
MARÍA E. ARCE; SUSANA I. SÁNCHEZ; FRANCISCO LÓPEZ AGUILERA; LEONARDO R. SEGUIN; ALICIA M. SELTZER; GLADYS M. CIUFFO
Revista:
NEUROPEPTIDES
Editorial:
CHURCHILL LIVINGSTONE
Referencias:
Lugar: Bethesda; Año: 2010
ISSN:
0143-4179
Resumen:
Abstract: Angiotensin II (Ang II) binds and activates two major receptors subtypes, namely AT1 and
AT2. In the fetus, AT2 receptors predominate in all tissues and decline shortly after birth, being
restricted to a few organs including brain. Interpretation of the function of Ang II in the cerebellum
requires a thorough understanding of the localization of Ang II receptors. The aim of the present paper
is to evaluate the localization of Ang II AT2 receptors in the Purkinje cell (PC) layer during
development. By binding autoradiography, a clear complementary pattern of AT1 and AT2 binding
labeled by [125I] Ang II was observed in young rats within the cerebellar cortex. This pattern was
present at the stages P8 and P15, but not at P30 and P60, where AT2 binding appears low and
superimposed with AT1 binding. We demonstrate that AT2 antibodies recognized postmitotic Purkinje
cells, labeling the somata of these cells at all the stages studied, from P8 to P60, suggesting that PCs
express these receptors from early stages of development until adulthood. In P8 and P15 animals, we
observed a clear correspondence between immunolabeling and the well-defined layer observed by
binding autoradiography. Confocal analysis allowed us to discard the co-localization of AT2 receptors
with glial fibrillary acidic protein (GFAP), a glial marker. Double immunolabeling allowed us to
demonstrate the co-localization of Ang II AT2 receptors with zebrin II, a specific PC marker. Since PCs
are the sole output signal from the cerebellar cortex and considering the role of cerebellum in
movement control, the specific receptor localization suggests a potential role for Ang II AT2 receptors
in the cerebellar function.