Patologia Animal, Escuela de Medicina Veterinaria y Zootecnia, Facultad de Ciencias Agropecuarias y Recursos Naturales, Villavicencio, Colombia.
Neuroimmunomodulation. 2010;17(6):386-95. doi: 10.1159/000292063. Epub 2010 May 27.
BACKGROUND/AIM: Prolactin (PRL), a hormone produced by the pituitary gland, has multiple physiological functions, including immunoregulation. PRL can also be secreted in response to stressful stimuli. During stress, PRL has been suggested to oppose the immunosuppressive effects of inflammatory mediators. Therefore, the aim of the present study was to analyze the effects of short- and long-term hyperprolactinemia on the inflammatory response in rats subjected to acute or chronic cold stress.
Inflammatory edema was induced by carrageenan in male rats, and hyperprolactinemia was induced by injections of the dopamine receptor antagonist domperidone. The volume of inflammatory edema was measured by plethysmography after carrageenan injection. Additionally, the effects of hyperprolactinemia on body weight and serum corticosterone levels were evaluated.
Five days of domperidone-induced hyperprolactinemia increased the volume of inflammatory edema. No differences in serum corticosterone levels were observed between groups. No significant differences were found among 30 days domperidone-induced hyperprolactinemic animals subjected to acute stress and the inflammatory response observed in chronic hyperprolactinemic animals subjected to chronic stress. The results suggest that short-term hyperprolactinemia has pro-inflammatory effects. Because such an effect was not observed in long-term hyperprolactinemic animals, PRL-induced tolerance seems likely. We suggest that short-term hyperprolactinemia may act as a protective factor in rats subjected to acute stress. These data suggest that hyperprolactinemia and stress interact differentially according to the time period.
背景/目的：催乳素（PRL）是由垂体分泌的一种激素，具有多种生理功能，包括免疫调节。PRL 也可以响应应激刺激而分泌。在应激期间，PRL 被认为可以对抗炎症介质的免疫抑制作用。因此，本研究旨在分析短期和长期高催乳素血症对急性或慢性冷应激大鼠炎症反应的影响。
雄性大鼠用角叉菜胶诱导炎症性水肿，用多巴胺受体拮抗剂多潘立酮诱导高催乳素血症。角叉菜胶注射后通过体积描记法测量炎症性水肿的体积。此外，还评估了高催乳素血症对体重和血清皮质酮水平的影响。
多潘立酮诱导的 5 天高催乳素血症增加了炎症性水肿的体积。各组血清皮质酮水平无差异。30 天多潘立酮诱导的高催乳素血症的急性应激动物与慢性应激的慢性高催乳素血症动物的炎症反应之间没有显著差异。结果表明，短期高催乳素血症具有促炎作用。由于在长期高催乳素血症动物中未观察到这种作用，因此似乎存在 PRL 诱导的耐受。我们建议，短期高催乳素血症可能在急性应激大鼠中起保护作用。这些数据表明，高催乳素血症和应激根据时间的不同而相互作用。
