Antiphlogistic action of phenylbutazone in normal and adrenalectomized rats of different ages relation to the 5-hydroxytryptamine blood concentration.

The authors have attempted to demonstrate the effect of bilateral adrenalectomy on carrageenin-induced oedema and on the antiphlogistic action of phenylbutazone in relation to the changes of blood 5-hydroxtryptamine (5-HT) in rats of different ages (21 days, 42 days, 3 months and 18 months old). It was found that the influence of adrenalectomy on the antiphlogistic action of phenylbutazone and on the blood 5-HT concentration is related to the age of rats. The lowest antiphlogistic action of phenylbutazone was found in 21-day-old rats and highest in the 18-month-old ones. In adrenalectomized 21- and 42-day-old rats the antiphlogistic action is decreased and fully suppressed in rats 3 and 18 months old. Adrenalectomy does not influenced basal values of blood 5-HT concentration. Blood 5-HT in adrenalectomized rats with inflammationadrenalectomized rats 42 days and 3 months old with inflammation after injection of phenylbutazone an increase of 5-HT was observed, but in 18-month-old animals in which antiphlogistic action is highest a decrease of 5-HT was observed.