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

Abstract

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.

Keywords

• Scopolamine,convulsion,food deprivation,rat

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

Abstract

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.

Keywords

• Skopolamin,konvülsiyon,yem yoksunluğu,sıçan

References

1. 1. Enginar N, Nurten A. Seizures triggered by food intake in antimuscarinic-treated fasted animals: Evaluation of the experimental findings in terms of similarities to eating-triggered epilepsy. Epilepsia 2010;51(Suppl. 3):80-4.
2. 2. Nurten A, Enginar N. The evaluation of antimuscarinic-induced convulsions in fasted rats after food intake. Epilepsy Res 2006;72(2-3):171-7.
3. 3. Nurten A, Özerman B, Özen İ, Kara İ. The role of solid fluid intake in antimuscarinic-induced convulsions in fasted mice. Epilepsy Behav 2009:15(2):142-5.
4. 4. Büget B, Zengin Türkmen A, Allahverdiyev A, Enginar N. Antimuscarinic-induced convulsions in fasted animals after food intake: Evaluation of the effects of levetiracetam, topiramate and different doses of atropine. Naunyn-Schmiedeberg’s Arch 2016;389(1):57-62.
5. 5. Italiano D, Ferlazzo E, Gasparini S, Spina E, Mondello S, Labate A, et al. Generalized versus partial reflex seizures: a review. Seizure 2014;23(7):512-20.
6. 6. Pothos EN, Creese I, Hoebel BG. Restricted eating with weight loss selectively decreases extracellular dopamine in the nucleus accumbens and alters dopamine response to amphetamine, morphine, and food intake. J Neurosci 1995;15(10):6640-50.
7. 7. Karami KJ, Coppola J, Krishnamurthy K, Llanos DJ, Mukherjee A, Venkatachalam KV. Effect of food deprivation and hormones of glucose homeostasis on the acetyl CoA carboxylase activity in mouse brain: a potential role of acc in the regulation of energy balance. Nutr Metabol (Lond) 2006;3:15.
8. 8. Wu Q, Lemus MB, Stark R, Bayliss JA, Reichenbach A, Lockie SH, et al. The temporal pattern of cfos activation in hypothalamic, cortical, and brainstem nuclei in response to fasting and refeeding in male mice. Endocrinology 2014;155(3):840-53.

9. 9. Hwang BH, Guntz JM. Downregulation of corticotropin-releasing factor mRNA, but not vasopressin mRNA, in the paraventricular hypothalamic nucleus of rats following nutritional stress. Brain Res Bull 1997;43(5):509-14.
10. 10. Enginar N, Nurten A, Zengin Türkmen A, Büyüklü Ç. Scopolamine-induced convulsions in fasted animals after food intake: Sensitivity of C57BL/6J mice and Sprague-Dawley rats. Epilepsy Res 2015;112:150-3.
11. 11. Enginar N, Nurten A, Özünal ZG, Zengin A. Scopolamine-induced convulsions in fasted mice: The effect of duration of food deprivation. Epilepsia 2009;50(1):143-6.
12. 12. Squadrito F, Calapai G, Altavilla D, Cucinotta D, Zingarelli B, Campo GM, et al. Food deprivation increases brain nitric oxide synthase and depresses brain serotonin levels in rats. Neuropharmacology 1994;33(1):83-6.
13. 13. Maniscalco JW, Rinaman L. Overnight food deprivation markedly attenuates hindbrain noradrenergic, glucagon-like peptide-1 and hypothalamic neural responses to exogenous cholecystokinin in male rats. Physiol Behav 2013;121:35-42.
14. 14. Saal D, Dong Y, Bonci A, Malenka RC. Drugs of abuse and stress trigger a common synaptic adaptation in dopamine neurons. Neuron 2003;37(4):577-82.
15. 15. Adell A, Artigas F. The somatodentritic release of dopamine in the ventral tegmental area and its regulation by afferent transmitter systems. Neurosci Biobehav Rev 2004;28(4):415-31.