Centro de Estudios Farmacol?gicos y Bot?nicos (CEFYBO-CONICET-UBA), Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, 1121ABG Buenos Aires, Argentina.
Stress. 2011 Mar;14(2):216-26. doi: 10.3109/10253890.2010.532254.
All forms of stress, including restraint stress (RS) and lipopolysaccharide (LPS) administration, activate the hypothalamic-pituitary-adrenal (HPA) axis. LPS binds to a recognition protein (CD14) and toll-like receptor 2/4 in different cells and tissues, including the adrenal gland, to induce the production of cytokines and cause upregulation of cyclooxygenase and nitric oxide synthase (NOS) enzymes. Acute ethanol exposure activates the HPA axis, but in some conditions prolonged administration can dampen this activation as well as decrease the inflammatory responses to LPS. Therefore, this study was designed to evaluate the adrenal response to a challenge dose of LPS (50 μg/kg) injected i.p., after submitting male rats to RS, twice a day (2 h each time) for 5 days and/or ethanol administration (3 g/kg) by gavage also for 5 days, twice daily. At the end of the experiment, plasma corticosterone concentrations and adrenal gland content of prostaglandin E (PGE) and NOS activity were measured as stress mediators. The results showed that repetitive ethanol administration attenuated the adrenal stress response to LPS challenge alone and after RS, by preventing the increase in plasma corticosterone concentrations and by decreasing the PGE content and NOS activity in the adrenal gland. Therefore, we conclude that moderate alcohol consumption could attenuate the effects of psychophysical stress and impair an inflammatory response.
所有形式的应激，包括束缚应激（RS）和脂多糖（LPS）给药，都会激活下丘脑-垂体-肾上腺（HPA）轴。LPS 与不同细胞和组织中的识别蛋白（CD14）和 Toll 样受体 2/4 结合，包括肾上腺，诱导细胞因子的产生，并导致环加氧酶和一氧化氮合酶（NOS）酶的上调。急性乙醇暴露会激活 HPA 轴，但在某些情况下，长期给药会抑制这种激活，并降低对 LPS 的炎症反应。因此，本研究旨在评估雄性大鼠在 RS 后，每天两次（每次 2 小时）接受 5 天，或通过灌胃接受 5 天（每天两次）3 g/kg 乙醇给药后，对 LPS（50μg/kg）腹腔注射挑战剂量的肾上腺反应。在实验结束时，测量血浆皮质酮浓度和前列腺素 E（PGE）的肾上腺含量以及 NOS 活性作为应激介质。结果表明，反复乙醇给药可通过防止血浆皮质酮浓度升高并降低肾上腺中 PGE 含量和 NOS 活性，减轻 LPS 单独和 RS 后对肾上腺应激反应的影响。因此，我们得出结论，适度饮酒可以减轻心理生理应激的影响，并损害炎症反应。
