Wantana Reanmongkol, Sanan Subhadhirasakul, Chittima Pairat, Chaiya Poungsawai, and Wiparat Choochar

pp. 227 - 234

Abstract

The effects of the chloroform extract from the leaves of Dyera costulata Hook. f. (D. costulata) on
nociceptive response using writhing, hot plate and formalin tests in mice and the antipyretic activity in
yeast-induced fever in rats, were examined. General behavior was also examined using pentobarbitalinduced sleep and locomotor activity in mice. The LD₅₀ value of intraperitoneally injected D. costulata
extract in mice was 0.27 g/kg. Oral administration of D. costulata extract (100-400 mg/kg) dose dependently
decreased the number of contortions and stretchings induced by acetic acid and licking activity of the late
phase in the formalin test but not in the heat-induced pain in mice. The extract (100-400 mg/kg, p.o.) had no
significant effect on fever induced by yeast in rats. The D. costulata extract (100-400 mg/kg, p.o.) prolonged
the duration of pentobarbital-induced sleep but had no significant effect on locomotor activity in mice.
These results suggest that the D. costulata extract possesses marked analgesic but no antipyretic effect.