DURMUŞ BOLAT, SADULLAH BAHAR, AYTÜL KÜRÜM, MURAT ERDEM GÜLTİKEN

Ergin atlarda III, IV ve VI. çift kranial sinirlerin transversal kesit alanları ve myelinli akson sayıları

Ekstrinsik göz kaslarının motor uyarımını sağlayan n. oculomotorius, n. trochlearis ve n. abducensin transversal kesit alanları ve içerdiği myelinli akson sayılarının belirlenmesi amaçlandı. Çalışmada 3 dişi, 3 erkek yetişkin at kullanıldı. Doku örnekleri sinirlerin cavum subarachnoidealede seyreden bölümlerinden alındı. Parafin blokları hazırlanan dokular 4 μm kalınlığında transversal olarak rotary mikrotom ile kesildi, Masson trikrom ile boyandı. Sinirlerin kesit alanları Cavalieri metodu ile içerdikleri myelinli akson sayıları ise parçalama yöntemi ile araştırıldı. Sağ ve sol göze ait sinirlerin kesit alanları ve içerdikleri myelinli akson sayıları arasında istatistiki bir fark gözlenmediğinden sinirlerin akson sayıları taraf ayırt etmeksizin tek bir veri olarak (median) değerlendirildi. Sinir kesitlerinin alanları n. oculomotorius, n. trochlearis ve n. abducens için sırası ile 2.647 mm2, 0.511 mm2 ve 1.092 mm2 olarak, myelinli akson sayıları ise sırası ile 13.523, 2.034 ve 4.151 adet olarak tespit edildi. Atlarda III, IV ve VI. çift kranial sinirlerin transversal kesit alanlarının ve myelinli akson sayılarının belirlendiği çalışma sonuçlarının bu alandaki bilgi birikimine katkı sağlayacağı ve gelecekte yapılacak çalışmalara ışık tutacağı sonucuna varıldı.

Anahtar Kelimeler:

periferal sinirler, Equus, hayvan anatomisi, biyometri, kan dolaşımı, vücut ölçümleri, gözler, at, morfoloji, morfometri

The Area of cross sections and the number of myelinated axons of cranial nerves III, IV and VI of adult horse

It was aimed to determine the number of myelinated axons and the area of cross sections of oculomotor, trochlear and abducens nerves providing motor innervation of extrinsic muscles of the eye. The study included 3 male and 3 female adult horses. Tissue samples were taken from the part of nerve being in subarachnoid space. Paraffin blocks of tissues were prepared and cut with a rotary microtome transversely at a thickness of 4 μm and sections were stained with Massons trichrome. The area of cross sections was determined with Cavalieris method and the number of myelinated axons was calculated by fractionator technique. There were no statistically significance of cross sectional areas and the number of myelinated axons of the right and the left sides, thus the data belonging to both sides were accepted as a single data (median). The areas of cross sections of oculomotor, trochlear and abducens nerves were calculated to be 2.647 mm2, 0.511 mm2 and 1.092 mm2 and the number of myelinated axons 13.523, 2.034 and 4.151 respectively. The results of the study performed to determine the area of cross sections and the number of myelinated axons of III., IV. and VI. cranial nerves of the horse will contribute to the knowledge of this area and shed light on the studies to be conducted in the future.

Keywords:

peripheral nerves, Equus, animal anatomy, biometry, blood circulation, body measurements, eyes, horses, morphology, morphometrics,

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