Behavioral studies on alkaloids extracted from the leaves of Hunteria zeylanica.
The effects of a crude methanol extract, butanol- and chloroform-fractions, and a pure compound, corymine, extracted from the leaves of H. zeylanica on locomotor activity and rearing, pentobarbital-induced sleep, and drug-induced convulsions were studied in mice. The methanol extract dose-dependently decreased rearing without a significant effect on locomotor activity at doses of 15, 60 and 120 mg/kg. It did not significantly prolong the sleeping time but potentiated the convulsions induced by strychnine, but not that by either picrotoxin or pentylenetetrazole, at a dose of 120 mg/kg. The butanol-fraction significantly prolonged sleeping time at a dose of 125 mg/kg but did not affect either of the convulsive drugs. The chloroform fraction prolonged sleeping time at doses of 62.5 and 125 mg/kg and potentiated the convulsions induced by either strychnine or picrotoxin, but not that by pentylenetetrazole, at doses of 15, 30, 60 and 120 mg/kg. Corymine did not significantly prolong sleeping time, but potentiated the convulsions induced by either strychnine or picrotoxin, not by pentylenetetrazole, at doses of 2, 8 and 15 mg/kg. These results suggest that crude alkaloidal extracts of H. zeylanica leaves produce biphasic effects on the central nervous system (CNS), depression and stimulation, while the pure compound, corymine, has a unique central stimulatory effect in mice.
Leewanich
P
P
Division of Pharmacology, Research Institute for Wakan-Yaku (Oriental Medicines), Toyama Medical and Pharmaceutical University, Japan.
Tohda
M
M
Matsumoto
K
K
Subhadhirasakul
S
S
Takayama
H
H
Aimi
N
N
Watanabe
H
H
D000470:Alkaloids / Q000494:pharmacology* / Q000633:toxicity; D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology; D001208:Asia; D001522:Behavior, Animal / Q000187:drug effects*; D006993:Hypnotics and Sedatives / Q000494:pharmacology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009043:Motor Activity / Q000187:drug effects; D010424:Pentobarbital / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry*; D012890:Sleep / Q000187:drug effects
D000470:Alkaloids; D000927:Anticonvulsants; D006993:Hypnotics and Sedatives; D010936:Plant Extracts; D010424:Pentobarbital