Immunohistochemistry of neuron specific enolase NSE in the rat brain after single and repeated pentylenetetrazol PTZ induced epileptic seizures

Creative Commons License

Yardımoğlu Yılmaz M., İlbay G., Dalçık C., Dalçık H., Şahin D., Ateş N.

5nd National Congress of Neuroscience (V.Ulusal Sinirbilimleri Kongresi, Neuroanatomy Abstract Book, vol.5, pp.23-24, 2006 (Conference Book)


P25 Immunohistochemistry of neuron specific enolase (NSE) in the rat brain after single and repeated pentylenetetrazol (PTZ) induced epileptic seizures.

Yardimoglu M [1], Ilbay G [2], Dalcik C [3], Dalcik H [1], Sahin D [2], Ates N [2].

Neuron specific enolase (NSE) is a sensitive marker of neuronal damage in central nervous system (CNS) diseases including epilepsy. While multiple reports have documented elevation in NSE levels following neuronal injury in various neurologic disorders, limited knowledge is available about localization of NSE in human different brain regions after chemically induced seizures. Changes in NSE localization have not been analyzed clearly in the CNS after epileptic seizures. Therefore, the present work was designed to investigate changes in NSE immunoreactivity in different brain regions after pentylene tetrazol (PTZ) induced acute and chronic epileptic seizures in rats. Male Wistar rats were divided into three groups: 1- single dose of PTZ group; 2-repeated dose of PTZ group; 3-control group. Following PTZ injections, generalized seizures started with the clonus of the facial and the forelimb muscles, and continued with the neck and tail extensions, loss of straightening reflex. Eeach rat was sacrified and removed brains for microscopic examination. Serial paraffin sections (5 µm) were stained with cresyl fast violet (CFV) and NSE immunocytochemistry. The NSE immunoreactivity was expressed in the neuronal perikarya with dendrites in the control and seizing animals. In thalamus, the number of immunoreactive cells were significantly (p=0.006) increased in PTZ groups compared to the control group. In single dose of PTZ group, the number of NSE (+) neurons increased significantly (p<0.05) in hypothalamus compared to the other groups. However, in the repeated-PTZ group, the number of NSE(+) neurons decreased significantly (p<0.05) in the hypothalamus compared to the single dose of PTZ group. It was seen a possible correlation between the NSE immunoreactivity and Nissl staining in the neurons of the same brain regions. It was revealed that Nissl staining was less with CFV in repeated dose of PTZ group in these regions compared to the other groups. In conclusion our results indicated that in animal models NSE immunoreactivity is a valuable marker in determining the changes in the number of metabolically active neurons in various brain regions after single and repeated seizures.

Key words: Epileptic seizures; Pentylene tetrazol; Neuron Specific Enolase; Nissl; Rat brain.