Ertuğrul ÖĞÜN, Semih KÜÇÜKGÜÇLÜ, Bahar KUVAKİ, Osman YILMAZ, Alper BAĞRIYANIK, Ensari GÜNELİ

Sıçanlarda intratekal uygulanan esmolol'ün analjezik etkinliğinin ve nörotoksisitesinin değerlendirilmesi

Amaç: Bu çalışma ile sıçanlara intratekal uygulanan esmololün spinal düzeyde analjezik etkinliğinin olup olmadığı ve spinal korddaki histopatolojik etkisinin araştırılması amaçlandı. Yöntem: Çalışmada 24 adet Wistar sıçan kullanıldı. Sıçanlar dört gruba ayrılarak, 10 JİL volüm içinde Grup Ve %0.9 NaCl (kontrol grubu), Grup 2'ye 1 mg esmolol, Grup 3'e 2 mg esmolol, Grup 4'e 4 mg esmolol önceden yerleştirilmiş olan intratekal kateterden uygulandı. İlaç uygulamasından önce (0) ve uygulandıktan sonraki 5, 10, 20, 30, 45, 60 ve 90. dakikalarda, sıçanlara "Tail-Flick" testi uygulandı. Motor blok değerlendirmesi de yukarıda belirtilen süre ve zaman aralıklarında gerçekleştirildi. Nörotoksisite araştırması için medulla spinalisten kesitler alındı. Bulgular: Kontrol grubu ile karşılaştırıldığında grup 2 ve 3'de "Tail-Flick" süreleri arasında istatistiksel olarak anlamlı bir fark saptanmazken Grup 4' de "Tail-Flick" süreleri 5,10, 20 ve 30 dakikalarda diğer gruplara göre anlamlı olarak daha uzun bulundu (p0.05). Sonuç: Bu araştırmada sıçanlara intratekal uygulanan 4 mg esmolol bolus doz ile motor blok görülmeden 30 dakika süren analjezi sağlanmıştır. Ayrıca histopatolojik olarak nörotoksisite bulgularına rastlanmamıştır.

Anahtar Kelimeler:

Analjezikler, Enjeksiyon, spinal, Sıçan, Wistar, Nörotoksisite sendromları, Modeller, hayvan

Evaluation of the analgesic efficacy and neurotoxicity of intrathecally administered esmolol in rats

Objective: The aim of this study was to evaluate the analgesic effect and toxicity at spinal level when esmolol is administered intrathecally in rat. Methods: In this study, 24 Wistar rats were used. The rats were divided into four groups: 0.9 % NaCl was administered intrathecally to Group 1 (control); esmolol 1 mg to Group 2; 2 mg to Group 3; 4 mg to Group 4 in 10 JIL volume each. Tail-flick tests were performed on all groups, before administering drug (0) and at 5,10, 20, 30, 45, 60 and 90 minutes after drug administration. Motor block was also evaluated at these times. Samples of spinal cord were taken to evaluate neurotoxicity. Results: When compared with the control group there was no difference in tail flick times between group 2 and 3. In the fourth group however the Tail-Flick times at 5, 10 20 and 30 min were significantly longer than in the other groups (p<0.05). Motor block did not developed in either group after IT administration of esmolol. There were no statistically significant histopathological changes and histopathological scores were 0 in each group (p>0.05). Conclusion: In conclusion, this study, in which esmolol was used for the first time intrathecally, shows that 4 mg esmolol provides analgesia for 30 minutes without any motor block or histhopathological toxicity.

Keywords:

Analgesics, Injections, Spinal, Rats, Wistar, Neurotoxicity Syndromes, Models, Animal,

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