Depression and/or potentiation of cortical responses after status epilepticus in immature rats

Title:

Depression and/or potentiation of cortical responses after status epilepticus in immature rats

Creator:

Grigorij Tsenov and Pavel Mareš

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:200ca049-4458-4b86-a964-87bb4eca470f
uuid:200ca049-4458-4b86-a964-87bb4eca470f
issn:0862-8408

Subject:

Fyziologie člověka a srovnávací fyziologie, fyziologie, epilepsie, ontogeneze, potkan, physiology, epilepsy, ontogeny, Rattus norvegicus, status epilepticus, evoked potentials, frequency depression, 14, and 612

Type:

article, články, model:article, and TEXT

Format:

print, bez média, and svazek

Description:

Lithium-pilocarpine status epilepticus (SE) resulted in delayed changes of single cortical in terhemisperic (transcallosal) responses in immature rats. Low-frequency stimulation inducing depression and/or potentiation was studied to analyze possible dynamic changes in cortical responses. Status was elicited in 12-day-old (SE12) or 25-day-old (SE25) rats. Control siblings received saline instead of pilocarpine. Interhemispheric responses were elicited by stimulation of the sensorimotor region of the cerebral cortex 3, 6, 9, 13, or 26 days after status. A series of 5 biphasic pulses with intensity equal to twofold threshold were used for stimulation. The interval between pulses was 100, 125, 160, 200 or 300 ms, eight responses were always averaged. Peak amplitude of the first positive, first negative and second positive waves was measured and responses to the second, third, fourth and fifth pulse were compared with the first one. Animals after status epilepticus as well as lithium-paraldehyde controls exhibit a frequency depression at nearly all the intervals studied. An outlined increase of responses in SE rats in comparison with the controls three days after SE stayed just below the level of statistical significance. In addition, animals in the SE12 group exhibited potentiation of responses at this interval after SE. With longer intervals after SE, the relation between SE and control animals changed twice resulting in a tendency to lower amplitude of responses in SE than in control rats 26 days after SE. Rats in the SE25 group exhibited higher responses than controls 13 days after status, but this difference was not present at the longest interval after SE. Low-frequency stimulation did not reveal increased cortical excitability as a long-lasting consequence of status epilepticus induced in immature rats. In addition, the outlined differences between SE and control rats changed with the time after SE., G. Tsenov, P. Mareš., and Obsahuje bibliografii a bibliografické odkazy

Language:

English

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Source:

Physiological research | 2007 Volume:56 | Number:4

Harvested from:

CDK

Metadata only:

false