SCOPOLAMINE-INDUCED CONVULSIONS IN FASTED RATS AFTER FOOD INTAKE: THE EFFECT OF DURATION OF FOOD DEPRIVATION

Öz

Objective: Mice and rats fasted for 2 days and then treated with antimuscarinic drugs, scopolamine or atropine, develop convulsions soon after food intake. It has been demonstrated that deprivation of food for less than 48 h also causes convulsions in mice. Since there are differences in characteristics of the seizures between mice and rats, the present study evaluated whether rats also develop convulsions after being deprived of food for 3-24 h.

Material and Method: Rats were deprived of food for 3, 6, 18, 24 and 52 h. At the time of testing, the animals were treated i.p. with saline or 3 mg/kg scopolamine and given food 20 min later. All animals were observed for 30 min, checking for the incidence and onset of convulsions.

Results: The fasted animals treated with scopolamine developed convulsions after food intake. The incidence of convulsions was statistically significant in the 6, 18, 24 and 52 h deprived animals. However, neither the incidence nor the latency to seizures showed differences with respect to duration of food deprivation or fasting-induced weight loss.

Conclusion: The present results demonstrate that the scopolamine treated rats that fasted for 24 h or less developed seizures after refeeding intake, indicating that food deprivation in itself, rather than its duration, seems to be the principal factor in the development of these convulsions.

Anahtar Kelimeler

• Scopolamine,convulsion,food deprivation,rat

AÇ SIÇANLARA SKOPOLAMİN UYGULANMASI VE YEM VERİLMESİ İLE OLUŞAN KONVÜLSİYONLAR: YEM YOKSUNLUĞU SÜRESİNİN ETKİSİ

Öz

Amaç: İki gün aç bırakıldıktan sonra antimuskarinik, skopolamin veya atropin, uygulanan fare ve sıçanlar yeniden yedikten hemen sonra konvülsiyon geçirmektedirler. Farelerin 48 saatten daha kısa süre yemden yoksun bırakılmasıyla da konvülsiyon oluştuğu gösterilmiştir. Fare ve sıçanlar arasında nöbet özelliklerinde farklar olduğu için, bu çalışmada 3-24 saat açlık sonrası sıçanlarda konvülsiyon oluşumu araştırılmıştır.

Gereç ve Yöntem: Sıçanlar 3, 6, 18, 24 ve 52 saat yemden yoksun bırakıldı. Açlık sonrası, hayvanlara serum fizyolojik veya 3 mg/kg skopolamin i.p. uygulandı ve 20 dakika sonra yem verildi. Tüm hayvanlar konvülsiyon sıklığı ve konvülsiyon başlama süresi için 30 dakika izlendi. 

Bulgular: Skopolamin uygulanan aç hayvanlar yem yedikten sonra konvülsiyon geçirdi. Konvülsiyon sıklığı 6, 18, 24 ve 52 saat yemden yoksun bırakılan hayvanlarda istatistiksel olarak anlamlı bulundu. Ancak nöbet sıklığı ve başlama süresi açısından, yem yoksunluğu süresi veya açlığa bağlı ağırlık kaybı ile ilişkili bir farklılık ortaya çıkmadı.

Sonuç: Bu sonuçlar, 24 saat veya daha kısa süre aç bırakıldıktan sonra skopolamin uygulanan sıçanlarda yeniden yedikten sonra konvülsiyon oluştuğunu göstererek; sürenin değil, yemden yoksun kalmanın konvülsiyon oluşumunda ana etken olabileceğini işaret etmektedir.

Anahtar Kelimeler

• Skopolamin,konvülsiyon,yem yoksunluğu,sıçan

Kaynakça

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