P2Y₁receptor switches to neurons from glia in juvenile versus neonatal rat cerebellar cortex

• Main Authors: Sancesario Giuseppe, Martorana Alessandro, Vacca Fabrizio, Amadio Susanna, Volonté Cinzia
• Format: Article
• Language: English
• Published: BMC 2007-06-01
• Series: BMC Developmental Biology
• Online Access: http://www.biomedcentral.com/1471-213X/7/77

<p>Abstract</p> <p>Background</p> <p>In the CNS, several P2 receptors for extracellular nucleotides are identified on neurons and glial cells to participate to neuron-neuron, glia-glia and glia-neuron communication.</p> <p>Results</p> <p>In this work, we describe the cellular and subcellular presence of metabotropic P2Y₁receptor in rat cerebellum at two distinct developmental ages, by means of immunofluorescence-confocal and electron microscopy as well as western blotting and direct membrane separation techniques. At postnatal day 21, we find that P2Y₁receptor in addition to Purkinje neurons, is abundant on neuronal specializations identified as noradrenergic by anatomical, morphological and biochemical features. P2Y₁receptor immunoreactivity colocalizes with dopamine β-hydroxylase, tyrosine hydroxylase, neurofilament light chain, synaptophysin and flotillin, but not with glial fibrillary acidic protein for astrocytes. P2Y₁receptor is found enriched in membrane microdomains such as lipid rafts, in cerebellar synaptic vesicles, and is moreover visualized on synaptic varicosities by electron microscopy analysis. When examined at postnatal day 7, P2Y₁receptor immunoreactivity is instead predominantly expressed only on Bergmann and astroglial cells, as shown by colocalization with glial fibrillary acidic protein rather then neuronal markers. At this age, we moreover identify that P2Y₁receptor-positive Bergmann fibers wrap up doublecortin-positive granule cells stretching along them, while migrating through the cerebellar layers.</p> <p>Conclusion</p> <p>Membrane components including purinergic receptors are already known to mediate cellular contact and aggregation in platelets. Our results suggesting a potential role for P2Y₁protein in cell junction/communication and development, are totally innovative for the CNS.</p>