The Central Nervous System stimulant effects of the ethanolic extract from the toxic brazilian plant Pseudocalymma elegam

Abstract

The effects of the ethanolic extract from the Brazilian toxic plant Pseudocalymma elegans (Veil.) Kuhlm. upon the behavior of mice were studied. Mice that received 1.6 to 3 g/kg of body weight extract presented seizure-like signs dying with a mean latency of 8 min. The LD50 in this situation was estimated in 1.8 g/kg. Mice that received extract 1 g/kg i.p. were observed in an open field 30 min later, presented a decrease in the number of rearings and an increase in the freezing time, without significant differences in the number of crossings, grooming time or number of fecal boluses compared to the control group. Mice submitted to the same treatment and tested on the elevated plus-maze presented a reduction in the percentage of entries and in the time spent in the open arms of the maze. These animals reduced the locomotor activity measured automatically and presented no difference in the muscular tonus, measured by the time of permanence hanging from a wire. These data suggest that the plant extract has compounds with stimulant effects upon the central nervous system: In a lower dose (1 g/kg) we observed behavioral effects that suggest an anxiogenic action of the extract without affecting the muscular tonus, and higher doses resulted in convulsions and death.