Mohammad Ali Ebrahimi SAADATLOU, Hamed TAVOUSI, Rana KEYHANMANESH

The study of histogenesis of sheep fetus iris

Bu çalışmada, koyunlarda iris histogenezinin belirlenmesi için farklı ve belirli yaşlarda 32 adet koyun fetus örneği kullanıldı. Numune hazırlama ve tesbit sonrası, yaş durumları belirlenerek histolojik ve anatomik çalışmalar gerçekleştirildi. Histolojik çalışmalarda, H & E boyama ve diğer iki spesifik boyama (Verhoeff ve Masson’s Trichrome) kullanıldı. Elde edilen sonuçlar, iki katmanlı çanak formasyonunun ilk ayda oluşmasına rağmen retinanın anterior ve ceca bölümlerinden iris ayrılmasının ikinci ayda meydana geldiğini gösterdi. İrisin siliyer cisimden ayrılması üçüncü ayda tamamlandı. Üçüncü ayın başından itibaren, iris değişiklikleri oluşmuş ve onun iç açısının dış açısından daha büyük olabilmesi için sirküler şekli oval forma değiştiği ve bu durumun gebeliğin sonuna kadar muhafaza edildiği gözlemlendi. Pupilin genel şekli iris genel şekli ile uyumlu bulundu. Histolojik olarak ortaya çıkan bulguda, iris ikinci ayda dış ve iç katmanların bağlantı yerindeki optik çanağın anterior bölümünü oluşturduğu ve bundan sonra yüzeysel ektodermin bir kısmının ve koroidin buna eklendiği belirlendi. Iris elastik liflerinin yanı sıra düz kasların görünümünün ilk belirtileri ikinci ayda anlamlı bulundu. Posterior hücreler iris hücre formasyonu başlangıcından itibaren pigmentli halde gözlemlendi. Irisin anterior epitel dokusu, üçüncü ayda stabilize olan onun posterior epitelini oluşturan basit skuamöz ve iki katmanlı kübik hücreler şeklinde olduğu belirlendi. Kollajen ve elastik lifler ve düz kasların sayısı ve onların büyüklüğünün yaş ile arttığı sonucuna varıldı.

Anahtar Kelimeler:

koyun, yaş farklılıkları, hayvan anatomisi, hayvan dokuları, biyolojik gelişim, kollajen, gözler, dölüt, morfoloji, retina, düz kas

Koyun fetus irisinin histogenesisi üzerine bir çalışma

In this study, for determination of histogenesis of iris in sheep, 32 samples of sheep fetuses at different and certain ages were used. After sample preparation and fixation, their age were determined and histological and anatomical studies were done. In histological studies, the H&E staining and two other specific staining (verhoeff and Masson’s Trichrome) were used. Obtained results demonstrated that a two-layered cup formed in first month but iris separation from the anterior and ceca part of retina occurred in second month. The separation of iris from ciliary body was completed in third month. From the beginning of third month, the iris formed changes and its circular shape changed to oval form so that its internal angle was larger than its external angle and this condition was retained until the end of pregnancy. General shape of pupil conformed to general shape of iris. It was histologically revealed that iris was formed from the anterior part of the optic cup just at the connection place of outer and inner layers in second month and thereafter a part of superficial ectoderm and choroid was added to it. The first signs of elastic fibers in iris as well as smooth muscles appearance were significant in second month. The posterior cells are pigmented from the beginning of the iris cell formation. Anterior epithelial tissue of the iris was simple squamous and two layer cuboidal cells formed its posterior epithelium which were stabilized in third month. The number of collagen and elastic fibers and smooth muscles and their size increase with age.

Keywords:

sheep, age differences, animal anatomy, animal tissues, biological development, collagen, eyes, fetus, morphology, retina, smooth muscle,

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