Cerebral serotonin depletion induces egocentric learning improvement in developing rats.
Egocentric learning ability of developing serotonin (5-HT)-depleted female rats was evaluated in the Morris maze test. 5-HT depletion was accomplished by a unique intracisternal injection of 5,7-dihydroxytriptamine at 21 days-old. A first behavioral test was applied before the lesion procedure. The animals were thereafter challenged to resolve the same test at 40 and 60 days-old. 5-HT depletion caused a dual effect on the rats' egocentric learning ability, i.e. at 40 days; control rats learned the task while the experimental rats were unable to learn it. At 60 days, control animals were unable to learn the test, while the experimental rats showed a successful performance. These results strongly suggest that 5-HT neurotransmission is necessary for egocentric learning establishment and regulation.
Olvera-Cortés
E
E
Laboratorio de Psicobiología, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro Social, A.P. 7-70; C.P. 58261, Morelia, Michoacán Mexico. maesolco@yahoo.com
Barajas-Pérez
M
M
Morales-Villagrán
A
A
González-Burgos
I
I
D015116:5,7-Dihydroxytryptamine / Q000494:pharmacology; D000367:Age Factors; D000818:Animals; D001921:Brain / Q000254:growth & development* / Q000378:metabolism*; D005260:Female; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology*; D008568:Memory / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000378:metabolism*; D018490:Serotonin Agents / Q000494:pharmacology; D013028:Space Perception / Q000502:physiology
D018490:Serotonin Agents; D015116:5,7-Dihydroxytryptamine; D012701:Serotonin