Ebru BALLI, Banu ÇOŞKUN, Ş. Necat YILMAZ, Aynur ÖZGE, Ülkü ÇÖMELEKOĞLU

Effect of cypermethrin on ısolated frog sciatic nerve: an ultrastructural study

Amaç: Cypermethrin tip 2 pyrethroid insektisitlerin önemli bir temsilcisidir. Bu çalışmada cypermethrinin izole kurbağa siyatik siniri ultrastrüktürü üzerine etkisinin incelenmesi amaçlanmıştır. Yöntemler: 28 kurbağa seçilmiş ve rastgele dört gruba bölünmüştür (n = 7). Dekapitasyondan sonra siyatik sinirler izole edilmiştir. Kontrol grubu dışındaki bütün sinirlere 30 (grup 1), 45 (grup 2) ve 60 (grup 3) dakika 2.5 uM cypermethrin uygulanmıştır. Doku örnekleri transmisyon elektron mikroskobunda incelenmiştir. Bulgular: Cypermethrin uygulanan tüm gruplarda miyelin kılıfta dejenerasyon, axonal hasar, mikrotübül ve nörofılament sayısında azalma ve mitokondrilerde hasar gözlenmiştir. Sonuç: Bulgularımız cypermethrinin tüm gruplarda miyelin kılıf ve aksonu etkileyerek sinir impuls iletiminde bozulmaya yol açtığını düşündürmektedir. Bu bulgulara ek olarak mitokondri dejenerasyonu ve mikrotübül sayısındaki azalmanın da sinir iletiminin bozulmasında önemli rol oynayabileceği düşünülmüştür.

Cypermethrinin kurbağa izole siyatik siniri üzerine etkileri: ultrastrüktürel bir çalışma

Aim: Cypermethrin is a. potent representative of the type 2 pyrethroid insecticides. This study aimed to investigate the ultrastructural effects of cypermethrin on isolated frog sciatic nerve. Materials and Methods: 28 Bana ridibunda frogs were chosen and randomly divided into four groups (n = 7). After decapitation, sciatic nerves were isolated. All nerves except the control group were exposed to 2.5 uM cypermethrin in Ringer's solution for 30 (group 1), 45 (group 2) and 60 (group 3) minutes, respectively. Tissue samples were evaluated by transmission electron microscope. Results: Degeneration in the myelin sheath and axon, decrease in the number of microtubules and neurofilaments, and evident damage in mitochondria were observed in all treated groups. Conclusions: Our findings suggest that cypermethrin affects both the myelin sheath and the axon in all groups, thereby impairing the nerve impulse conduction. In addition to these findings, notable degeneration of mitochondria and decrease in numbers of microtubules may also play an important role in this nerve conduction impairment.

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