Jj. Waite et Lj. Thal, THE BEHAVIORAL-EFFECTS OF HEPTYLPHYSOSTIGMINE ON RATS LESIONED IN THENUCLEUS BASALIS, Neuroscience research, 21(3), 1995, pp. 251-259
The time course and dose dependence of acetylcholinesterase inhibition
in three regions of brain were measured for the long-acting physostig
mine derivative, heptylphysostigmine (HP). Behavioral studies were per
formed on rats lesioned with ibotenic acid in the nucleus basalis magn
ocellularis (nBM) using doses of HP that inhibit cholinesterase activi
ty 20%, 40%, and 60% 2 h after injection. Spatially-cued learning and
memory were tested in the water maze. Lesioned animals that received h
igher doses of HP showed a trend towards improvement in the acquisitio
n of this task, but this was not statistically significant. Swimming s
peed was reduced in the group receiving the highest dose of HP in comp
arison with a lower dose. The acoustic startle response was diminished
in all groups given HP in comparison with both lesioned and sham-lesi
oned saline-injected controls. Open field activity was slightly enhanc
ed by the presence of the nBM lesion. HP reduced the hyperactivity in
a dose-dependent manner. Deficiencies in limb strength or coordination
were not detected. These results suggest that HP may decrease spontan
eous, stressed, or reflexive activity, although an effect on the spati
al learning deficit produced by an ibotenic acid lesion of the nucleus
basalis was not detected.