An Investigation of Correlation between Electrophysiological and Functional Recovery after the Sciatic Nerve Injury

Year 2012, Volume: 37 Issue: 4, 177 - 185, 01.12.2012

Mustafa Güven İbrahim Kahraman İsmail Günay

Abstract

Purpose: Video or photo assisted footprint analysis method is used to determine the motor and sensorial development instead of classic walking track footprint analysis in experimental peripheral nerve injury. Besides, the sucrose-gap method is used for measuring the electrophysiological activity in the sciatic nerves in-vitro. The aim of this study is to investigate the relationship between functional and electrophysiological recovery during the nerve regeneration in Wistar rats. Methods: In the experiments, after the unilateral sciatic nerve crushing, the rats were evaluated at the preoperative and 2nd, 4th, 6th and 8th weeks postoperative using the sucrose gap method, and photo assisted footprint method. The compound action potentials (CAP), the Peak- time (PT) and the ½ Falling- time (1/2FT) were measured, and compared to functional results. Results: Two weeks after being crushed sciatic nerves, complete function loss was seen operated legs in all rats. The amplitude of CAP was determined too small. The PT and the 1/2FT values were three fold longer than intact. However, following 4th - 8th weeks, the amplitude of CAP and other parameters of CAP were closed to intact values. Conclusion: The findings indicated that the results of the functional recovery were correlated to electrophysiological results. However, functional results showed almost full functional recovery in the 4th week, the electrophysiological results did not reach to intact values in the 8th week. We conclude that photo assisted footprint analysis method and sucrose-gap technique, which are useful functional and electrophysiological methods to produce complementary knowledge with each other in the investigation of experimental peripheral nerve regeneration.

Keywords

Footprint, compound action potential, sucrose-gap, crush, regeneration, sciatic nerve

Siyatik Sinir Ezilmesinden Sonra Elektrofizyolojik ve Fonksiyonel İyileşme İlişkisinin Araştırılması

Abstract

Amaç: Deneysel periferik sinir yaralanmalarında motor ve duyusal iyileşmeyi belirlemek için klasik yürüme izi analiz yöntemi yerine, video ya da fotoğraf destekli footprint analiz yöntemi kullanılabilmektedir. Bunun yanında in-vitro bir yöntem olan sukroz-gap yöntemi de sıçan siyatik sinirlerinde elektrofizyolojik aktivitenin ölçülmesinde kullanılmaktadır. Bu çalışmadaki amacımız Wistar türü sıçanlarda, sinir rejenerasyonu sırasındaki fonksiyonel ve elektrofizyolojik iyileşme ilişkisini araştırmaktır. Yöntem: Çalışmalarımızda, siyatik sinirlerde tek taraflı ezildikten sonra, sıçanlar operasyon öncesi, 2., 4., 6. ve 8. haftalarda sukroz-gap ve fotoğraf destekli footprint yöntemi ile değerlendirildi. Bileşik aksiyon potansiyelleri (CAP), yükselme süresi (PT) ve ½ düşme süresi ölçüldü (1/2 FT) ve fonksiyonel sonuçlarla karşılaştırıldı. Bulgular: Siyatik sinirlerin ezilmesinden iki hafta sonra tüm sıçanların ezilmiş sinirin bulunduğu ayaklarda tam fonksiyon kaybı oldu. CAP genliği çok düşük olarak belirlendi. PT ve 1/2FT değerleri normal değerlerinden üç kere daha uzundu. Buna rağmen, takip eden 4. - 8. haftalarda, CAP genliği ve diğer CAP parametreleri normale yakın değerlere geri döndü. Sonuç: Bulgular, fotoğraf destekli footprint yöntemi sonuçları ile, elektrofizyolojik sonuçların yakın bağlantı içinde olduğuna işaret etmektedir. Bununla birlikte, fonksiyonel sonuçlar, 4. haftada neredeyse tam iyileşmeyi gösterirken, elektrofizyolojik ölçümler 8. haftaya kadar normal değerlere ulaşmadı. Sonuç olarak, fotoğraf destekli footprint analiz ve sukroz-gap yönteminin deneysel periferik sinir rejenerasyonun araştırılmasında birbirini tamamlayıcı bilgiler ürettiğini düşünüyoruz.

Keywords

Footprint, Bileşik sinir aksiyon potansiyeli, Sukroz-gap, Sinir rejenerasyonu, Siyatik sinir

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