Nagihan DAMAR, Sevda ÖZKARDEŞLER, Uğur KOCA, Ömür MAVİOĞLU, Zahide ELAR

Tavşanlarda oluşturulan medulla spinalis iskemi reperfüzyon modelinde diltiazem,insülün ve C vitamininin nöroprotektif etkileri

ve C vitamininin nöroprotektif etkilerinin araştırılması amaçlandı. Gereç ve yöntem: Yeni Zelanda tipi 24 adet beyaz tavşan randomize olarak dört gruba ayrıldı (her grupta n=6). Grup 1’de diltiazem kullanıldı. Grup 2’de diltiazeme ek olarak kan glukoz düzeyini 60-100 mg dl-1 arasında tutabilecek dozda 2-10 U sa-1 hızında intravenöz (İV) kristalize insülin infuze edildi. Grup 3’de Grup 2’deki ilaç tedavisine ek olarak iskemi öncesinde 500 mg İV C vitamini uygulandı. Dördüncü Grup’ta herhangi bir ilaç uygulaması yapılmadı. Otuz dakikalık suprarenal iskemi modeli yaratıldı. İskemi öncesi (bazal değer), iskeminin 5., 15. ve 30. dakikaları ile reperfüzyonun 5. ve 15. dakikasında arteriyel kan örnekleri alınarak kan gazları, potasyum, laktat ve glukoz değerleri çalışıldı. Postoperatif 1., 18. ve 24. saatlerde sağ kalım ve Tarlow skorlama sistemi kullanlarak nörolojik durum değerlendirmesi yapıldı. Bulgular: Zamana bağlı olarak kan pH değerlerindeki azalmanın ve kan laktat değerlerindeki artışın, tüm gruplarda istatistiksel olarak anlamlı olduğu saptandı (p

The neuroprotective efects of diltiazem,insulin and vitamin C in A rabbit medulla spinalis ischemia and reperfusion model

Objective: The neuroprotective effects of diltiazem, insulin and vitamin C on medulla spinalis ischemia and reperfusion, were investigated. Material and method: Twenty four New Zealand white rabbits were used. Animals were randomly divided into four groups. In Group 1 (n=6), diltiazem was used. In Group 2 (n=6), in addition to diltiazem, regular insulin was infused intravenously at a rate of 2-10 U h-1 to achieve a blood glucose level between 60-100 mg dl-1. In Group 3 (n=6), following the procedure that had been used in Group 2, 500 mg intravenous bolus vitamin C was administered before ischemia. In Group 4 (n=6) no medication was used. Arterial blood gases, potassium, lactate, glucose values were evaluated before the surgical intervention and 5., 15., 30. minutes following clamping and 5., 15. minutes after unclamping of the aorta. Neurological status was assessed via Tarlow Scoring System at the 1, 18 and 24th hours. Results: Significant decrease in blood pH values and increase in blood lactate values were obtained throughout the study in all groups. Decreases in blood pH in groups 1 and 4 were statistically significant compared to group 2 and 3. Increases in blood lactate levels were statistically significant when group 4 was compared with the other groups and when group 1 was compared with either groups 2 or 3 (p<0.05). We did not observe any neurological deficit at the end of 24 hours in groups which insulin was used (p<0.05). All animals were paraplegic in the group 4. The animals in group 1 were paraplegic at the first hour and they developed paraparesia at the 24th hour. Conclusion: We conclud that although diltiazem pretreatment provides some neuroprotective effects against spinal cord ischemia and reperfusion injury, adding insulin and vitamin C to diltiazem pretreatment causes more effective neuroprotection.

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