The modulatory role of β‑amyloid in the regulation of nociception in mice

Abstract

β‑amyloid is an important factor in the pathophysiology of Alzheimer’s disease. This study investigates β‑amyloid’s role in the regulation of nociception in mice. Pretreated once, 2 weeks prior to testing with β‑amyloid, male ICR mice were examined on various nociceptive tests. Pretreatment with β‑amyloid reversed the nociceptive effects induced by intraperitoneally administered acetic acid (writhing response) and intraplantar injection of 5% formalin into the hind paw. β‑amyloid pretreatment also elevated the threshold for nociception in the mechanical von Frey test. Additionally, p‑CREB and p‑ERK levels in the spinal cord and the adrenal gland increased after formalin injection. Pretreatment with β‑amyloid attenuated formalin‑induced overexpression of p‑CREB and p‑ERK in the spinal cord and the adrenal gland. Our results suggest that chemical and mechanical nociception appear to be altered in β‑amyloid‑treated animals. Furthermore, the reduction of nociception by β‑amyloid in the formalin pain model appears to be mediated, at least in part, by the suppression of p‑CREB and p‑ERK level in the spinal cord and the adrenal gland.