RESUMO
Prolactin (PRL) and glucocorticoids are hormones involved in the regulation of the immune system. Rheumatoid arthritis (RA) is an inflammatory condition that presents a diurnal rhythm of disease activity. PRL/cortisol ratio, and IL-1beta and TNF-alpha levels were determined in patients with RA and in control subjects at 0600, 1000, 1400, 1800, 2200, and 0200 hours. In patients with RA we observed higher PRL/cortisol ratio at 0200 hours, whereas IL-1beta and TNF-alpha reached their highest serum levels at 0200 and 0600 hours. In patients with RA we observed an imbalance in favor of proinflammatory hormones as opposed to levels of antiinflammatory hormones during nocturnal hours together with increased levels of IL-1beta and TNF-alpha of the diurnal rhythm of disease activity.
