Endoplasmic reticulum stress in rat acute pancreatitis: Role of atrial natriuretic peptide.

ANA PAULA COURREGES; ANA CLARA NAJENSON; MARCELO S. VATTA; LILIANA G. BIANCIOTTI

Buenos Aires

Congreso; Reunión Conjunta de Sociedades Biomédicas.; 2017

Sociedad Argentina de Investigación Clínica

In previous studies we showed that ANF attenuates the severityof experimental acute pancreatitis (AP) by reducing trypsinogenactivation and the inflamatory response. Recent studies supportthat endoplasmic reticulum (ER) stress precedes these events. ERstress, which occurs when misfolded or unfolded proteins accumulatewithin the organelle, triggers the unfolded protein response(UPR) which aims to restore ER homeostasis. In this sense wepreviously reported that ANF inhibits the expression of BiP (majorchaperone controlling UPR) and eIF (protein translation regulator)whereas it increases CHOP (apoptosis inducer) and improvesER swelling. In the present work we advanced in the knowledgeof ANF effect on the signaling pathways involved in the UPR. APwas induced in Sprague-Dawley strain rats (200-220g) by four repetitivecerulein injections (40μg/Kg). Thirty minutes before the firstcerulein injection animals were infused with either saline (control)or ANF (1μg/Kg/h) for 60 min. Following euthanasia (60 min afterthe last cerulein injection) pancreatic samples were harvested forimmnunoblotting and fluorometric assays. ANOVA followed by aStudent?s t test modified by Bonferroni was used for statistical analysis.Results are expressed as the means±S.E.M. and p values of0.05 or less were considered statistically significant. ANF did notchange PERK activation or sXBP-1, factors which favor cell survival.However it decreased Bcl-2 expression in both control (P