Thymulin reduces hyperalgesia induced by peripheral endotoxin injection in rats and mice.

In a new model of peripheral localized inflammation, induced by intraplantar endotoxin (1.25 micrograms) injection in the hind paw of rats and mice, thymulin, a hormone of the thymus gland involved in immunomodulation, reduced inflammatory pain. High doses of thymulin reduced significantly, and in a dose-dependent manner, mechanical hyperalgesia as assessed by the paw pressure test and thermal hyperalgesia as assessed by the hot plate test and tail immersion test.