BACKGROUND: Several studies have demonstrated antinociception induced by exercise; however, the specific mechanisms for this effect are not well understood. Thus, we investigated the involvement of α2-adrenergic receptors (α2-ARs) in the antinociceptive effect produced by exercise in rats and mice. METHODS: Male Wistar rats performed acute aerobic (AA) and acute resistance exercise protocols, and male α2A/α2C-ARs knockout mice and their wild-type mice were also submitted to AA. RESULTS: After the exercise protocols, the nociceptive threshold of rats and wild type was increased, (except in knockout mice). This effect was reversed by yohimbine, a nonselective α2-ARs antagonist (4 mg/kg, subcutaneously [s.c.]); rauwolscine, a selective α2C-ARs antagonist (4 mg/kg, s.c.); BRL 44408, a selective α2A-ARs antagonist (4 mg/kg, s.c.) and guanethidine, a selective inhibitor of transmission in adrenergic nerves (30 mg/kg, intraperitoneal). Furthermore, when given intrathecally or intracerebroventricularly, yohimbine did not alter antinociception induced by exercise protocols. In addition, α2-ARs expression in rat brains did not change after AA and acute resistance exercise. CONCLUSION: These results suggest a peripheral involvement of α2-ARs in the antinociception induced by aerobic and resistance exercise.
BACKGROUND: Several studies have demonstrated antinociception induced by exercise; however, the specific mechanisms for this effect are not well understood. Thus, we investigated the involvement of α2-adrenergic receptors (α2-ARs) in the antinociceptive effect produced by exercise in rats and mice. METHODS: Male Wistar rats performed acute aerobic (AA) and acute resistance exercise protocols, and male α2A/α2C-ARs knockout mice and their wild-type mice were also submitted to AA. RESULTS: After the exercise protocols, the nociceptive threshold of rats and wild type was increased, (except in knockout mice). This effect was reversed by yohimbine, a nonselective α2-ARs antagonist (4 mg/kg, subcutaneously [s.c.]); rauwolscine, a selective α2C-ARs antagonist (4 mg/kg, s.c.); BRL 44408, a selective α2A-ARs antagonist (4 mg/kg, s.c.) and guanethidine, a selective inhibitor of transmission in adrenergic nerves (30 mg/kg, intraperitoneal). Furthermore, when given intrathecally or intracerebroventricularly, yohimbine did not alter antinociception induced by exercise protocols. In addition, α2-ARs expression in rat brains did not change after AA and acute resistance exercise. CONCLUSION: These results suggest a peripheral involvement of α2-ARs in the antinociception induced by aerobic and resistance exercise.
Authors: Giovane Galdino; Thiago Romero; José Felippe Pinho da Silva; Daniele Aguiar; Ana Maria de Paula; Jader Cruz; Cosimo Parrella; Fabiana Piscitelli; Igor Duarte; Vincenzo Di Marzo; Andrea Perez Journal: Anesth Analg Date: 2014-09 Impact factor: 5.108
Authors: Martina Ferioli; Giorgio Zauli; Alberto M Martelli; Marco Vitale; James A McCubrey; Simona Ultimo; Silvano Capitani; Luca M Neri Journal: Oncotarget Date: 2018-02-08