Findings of Somatosensory Evoked Potential to Stimulation of the Sciatic Nerve in Two Different Rat Strains.

Abstract

Abstract:No comparative study about somatosensory evoked potentials (SEP) on different rat strains has been done yet. It is evident that comparative SEP studies are important since different rat strains have different physiological properties. We aimed to compare early latency SEP values from stimulation of sciatic nerve in Wistar (Wr) and Sprague-Dawley (SDr) rats which are frequently used rat strains in experimental studies. In Wr group, the mean of first far field potential (Ff1) latency was shorter and the mean Ff1 amplitude was lower than that of Sprague-Dawley rat group. Mean cortical potential latency in Wr group was longer than that of SDr group while amplitude was not different. Central conduction time (CCT) in Wistar rat group was found to be longer than that of SDr group. Shorter Ff1 latency in Wr group implies that afferent volley reaches cervical posterior fasciculus from sciatic nerve earlier than SDr group while longer CP latency implies that afferent volley reaches cortex later than SDr group. Similarity between the latencies of lumbar potentials implies that peripheral conduction velocity has no effect on the difference of Ff1 latencies. Key words: central conduction time, somatosensory evoked potentials, Sprague-Dawley rat, Wistar rat Materials and MethodsThe female rats investigated were 10-12 weeks old and a total of 12 Wr and 12 SDr rats were included in the study. Both groups were kept under the same conditions, i.e. temperature was between 22-25°C, relative humidity was about 50%, and the light-dark cycle was 12:12 hr. During and after the study none of the animals were killed or disabled. Recordings were done under general anesthesia which was achieved by injecting intraperitoneally a mixture of 12 mg/kg xylazine and 75 mg/kg ketamine. Two-channel recording was

Comparison of ATP-MgCl2 and Methylprednisolone in Experimentally Induced Spinal Cord Trauma

“…[25] yaptıkları çalışmada tibial sinir uyarımıyla torakal 1. ve 2. vertebraların prosessus spinozusları arasından kayıt alarak latansı 3,3±1,4ms, korteks bölgesi için ise 13,9±1,7ms olarak hesaplamışlardır. Oğuzhanoğlu ve Kurt [26] ise yaptıkları çalışmada bu çalışmada olduğu gibi siyatik sinir stimülasyonu ile lumbal 1. vertebra seviyesinden ve korteksten kayıt almışlardır ve buldukları latans değerleri sırasıyla 1,81ms ve 19,88±1,64ms' dir. Bu çalışmada ise kaudalden kaydedilen normal SEP kaudal latans (K-ANP) değerleri FTS, MP ve ATP grupları için sırasıyla 2,40±0,09ms, 2,33±0,17ms ve 2,42±0,18ms' dir.…”

“…Bazı çalışmalarda tibial uyarımla kaydedilen sağlıklı rat kortikal latans değerleri 20,53±0,78ms [24] ve 13,9±1,7ms' dir [25]. Siyatik sinirin stimülasyonuyla elde edilen kayıtta ise kortikal latans 22,39ms olarak bildirilmiştir [26]. Bu çalışmada elde edilen normal kortikal latans değerleri FTS, MP, ATP grupları için sırasıyla 14,34±0,76ms (n=8), 14,96±2,13ms (n=8), 17,90±1,03ms (n=7)' dir.…”

“…Bu çalışmada elde edilen normal kortikal latans değerleri FTS, MP, ATP grupları için sırasıyla 14,34±0,76ms (n=8), 14,96±2,13ms (n=8), 17,90±1,03ms (n=7)' dir. Bu sonuçlar Oğuzhanoğlu ve Kurt' un [26] bildirdiğinden küçük olmakla birlikte Hu ve ark. 'nın [25] sonuçlarına benzerdir.…”

Effects of L‐arginine on the brain ischaemia‐reperfusion damage in rats: An investigation by somatosensory evoked potentials and histopathology

“…Somatosensory evoked potential (SEP) recordings: At the end of the 72-hour reperfusion period SEPs were collected by a Medelec Premiere-Plus recording unit as described earlier (14). The sweep duration was set to 30 ms and the signals were filtered (low and high band pass 0.1 Hz and 10 KHz).…”