IHEM   20887
INSTITUTO DE HISTOLOGIA Y EMBRIOLOGIA DE MENDOZA DR. MARIO H. BURGOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Early and late onset of inflammation affects AT2R expression levels and subcellular localization in different subpopulations of nociceptors
Autor/es:
ACOSTA CG; SELTZER, AM; BENITEZ S,
Lugar:
Mar del Plata
Reunión:
Congreso; XXXII CONGRESO ANUAL SAN 2017; 2017
Institución organizadora:
Sociedad Argentina de Investigación en Neurociencias
Resumen:
Pharmacological evidence suggests that the type 2 receptor for angiotensin II (AT2R) plays a role in relieving neuropathic pain, an effect that has been attributed to both inhibition (by EMA401) and activation (by mycolactone) of the receptor. Thus, more research is needed to uncover the underlying mechanisms. We injected Complete Freund's Adjuvant (CFA) into the hindpaw of female Wistar rats and analyzed the effect 1 (CFA1) and 4 (CFA4) days thereafter.We combined immunohistochemistry with a detailed quantification analysis to examine a)subcellular localization and b) relative levels of AT2R. We found that AT2R was restricted to both small and medium size dorsal root ganglion neurons that either bound IB4 or expressed TrkA or both. These markers indicated that AT2R expressing neurons were C and A-delta nociceptors. The intracellular localization of AT2R varied amongst the neurons. We observed two patterns: retracted to the peri-nuclear region or evenly distributed to the cell membrane.Membrane-associated staining is likely to reflect functional AT2R whereas cytoplasmic distribution reflects receptor synthesis and availability. Hence, we measured both signals and compare them across neuronal sizes. At CFA1 the receptor level increased significantly only at the cell edge of small neurons, whereas at CFA4 AT2R levels increased only at the edge of medium neurons. This pattern could partly explain the dual behavior observed for AT2R in pathological pain models.