KAINIC ACID MODIFIES BURYING BEHAVIOR IN RATS
Abstract number :
2.061
Submission category :
Year :
2003
Submission ID :
3655
Source :
www.aesnet.org
Presentation date :
12/6/2003 12:00:00 AM
Published date :
Dec 1, 2003, 06:00 AM
Authors :
Raymundo B[aacute]ez, Alonso Fern[aacute]ndez-Guasti, Luisa L. Rocha Farmacobiologia, CINVESTAv-IPN, Mexico, D.F., Mexico; Facultad de Psicologia, UNAM, Mexico, D.F., Mexico
Approximately 50% of patients with temporal lobe epilepsy (TLE) present anxiety symptoms. Two factors are crucial for this propensity: the neuropathological epileptic substrate and its chronicity. The main goal of the present study was to evaluate the anxiety behavior using a burying behavior test in rats pretreated with kainic acid (KA), which is a model of TLE associated with progressive hippocampal damage.
Male Wistar rats received an administration of KA (9 mg/kg i.p.) that produced status epilepticus. Seven (n=9 ), 28 (n=7) and 180 (n=12 ) days after KA, animals were used to evaluate the burying behavior test consisting of the exposure to a shock-probe inserted in a cage. Four measures were estimated during 10 min: burying latency (BL), burying time (BT), rearing time (RT) and number of shocks received (SH). Every group was properly compared to a saline treated group.
When compared with controls, BL was longer in KA rats ([italic]Kruskal-Wallis =43.417, p[lt]0.05)[/italic], while BT was shorter ([italic]Kruskal-Wallis=9.34, p[lt]0.05[/italic]) at all times evaluated. Nevertheless, there was not an intratreatment effect. No differences were detected in RT ([italic]Kruskal-Wallis=6.11, p[gt]0.05) [/italic]and SH ([italic]Kruskal-Wallis=9.34, p[gt]0.05[/italic]) evaluations in KA treated rats when compared with controls.
The results obtained in this study suggest that the anxiolytic effect (BT) observed from the seventh day after KA is neither associated to the progressive epileptogenic effect nor the neuronal damage beyond that day. However, it could be related to the characteristic hippocampal damage observed 24h. post KA administration. Although this effect could be masked by hyporeactivity (BL), it is not associated neither with nociception (SH) nor with exploratory behavior (RT). Since KA produces hippocampal lesions and this brain area participates in the control of burying behavior, the results here observed should be cautiously interpreted.
[Supported by: CONACYT 31702-M and Fundaci[oacute]n Miguel Alem[aacute]n.]