[Effects of estrogens on learning of rats with chronic brain cholinergic deficit in Morris water maze].
A chronic deprivation of brain cholinergic functions in rats caused by intracerebroventricular injection of neurotoxin AF64A increases the escape latency in Morris water maze test as compared to control sham-operated animals. Measurements and analysis of rat movement tracks using an original computerized "Behavioral Vision" system revealed the ability of 17 beta-Estradiol and its synthetic isomer J-861 (both administered daily in per os dose 0.2 mg/kg during 7 days before and 10 days after a single intracerebroventricular injection of AF64A) to improve learning of the animals. Directivity of search trajectories was estimated by a novel index of track straightness. The introduction of an index of "passive swimming" made it possible to reveal episodes of immobility in water-maze behavior of AF64A-injected animals. Unlike J-861, 17 beta-Estradiol almost completely eliminated these episodes. The newly developed indices (especially straightness) seem to be very useful in differentiating learning ability of rats from a decrease in their mobility in the Morris water-maze test, in particular, in case of the estrogens under study.
Mukhina
T V
TV
Institute of Physiologically Active Compounds, Russian Academy of Sciences, Chernogolovka, Moscow Oblast. mukhina@ipac.ac.ru
Lermontova
N N
NN
Van'kin
G I
GI
Oettel'
M
M
Pachev
V K
VK
Bachurin
S O
SO
D000818:Animals; D001388:Aziridines / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000378:metabolism*; D002794:Choline / Q000031:analogs & derivatives* / Q000494:pharmacology; D004195:Disease Models, Animal; D004958:Estradiol / Q000494:pharmacology*; D007858:Learning / Q000187:drug effects*; D008297:Male; D008568:Memory / Q000187:drug effects*; D009466:Neuromuscular Blocking Agents / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011950:Receptors, Cholinergic / Q000172:deficiency* / Q000187:drug effects; D013550:Swimming
D001388:Aziridines; D009466:Neuromuscular Blocking Agents; D011950:Receptors, Cholinergic; D004958:Estradiol; C044894:ethylcholine aziridinium; D002794:Choline