In vitro and in vivo effects of serine and threonine on follicle growth differentiation and atresia

Bu çalışma, serine ve threonine amino asitlerinin foliküler büyümeye, farklılaşmaya ve dejenerasyona etkilerini in vivo ve in vitro koşullarda araştırmak için planlandı. Bu amaçla biri in vitro diğeri ise in vivo olmak üzere iki deney düzenlendi. Birinci deneyde, 21 günlük ev faresine ait foliküller kültürde dört değişik işleme (kontrol, pozitif kontrol (Gebe kısrak serum gonadotropini, PMSG), serine/threonine (AA) ve AA + PMSG ) tabi tutularak her 24 saatte bir foliküllerin çapları ölçüldü, ikinci deneyde aynı farelere izotonik tuz çözeltisi (kontrol) ve 165 nmol. serine ile 70 nmol threonine içeren bir karışım (test) günde bir kez beş gün boyunca enjekte edildi. Son enjeksiyondan sonra hayvanlara servikal dislokason yapıldı, sonra ovaryumlar histolojik analizler için alındı. Alınan organlar mikrotomla 10 um kalınlıkta kesildikten sonra eosin ve hematoksilin ile boyandı. Kesitler üzerindeki foliküller mikroskop altında çaplarına göre, antrum oluşumuna göre ve dejenere olup olmadıklarına göre sınıflandırılarak sayıldı. Birinci deneyde amino asitlerin primer folikül gelişimine bir etkisinin olmadığı belirlendi, ikinci deneyde amino asit enjeksiyonu primer foliküller ile dejenerasyona uğrayan erken antral safhadaki folüküllerin sayısının azalmasına sebep olur iken antral safhadaki sağlıklı foliküllerin sayısını artırdı. Sonuç olarak in vitro koşullarda serine ve threonine amino asitlerinin yanlız veya PMSG ile birlikte kültüre ilavesinin küçük foliküllerin büyümesine etkisi olmadığı fakat bu amino asitlerin enjeksiyonu primer foliküllerin ve dejenere olmuş erken antral safhadaki foliküllerin sayısını azaltığı, antral safhadaki sağlıklı foliküllerin sayısını da artırdığı belirlenmiştir.

Serine ve threonine amino asitlerinin in vitro ve in vivo koşullarda fare foliküllerinin büyümesine, farklılaşmasına ve dejenerasyonuna etkisi

This work was designed to test the effect of serine and threonine on follicle growth, differentiation and atresia under in vitro and in vivo conditions. Two experiments were conducted. In the first experiment, follicles 90-120 urn in diameter, from 21-day old mice, were dissected mechanically and cultured individually for 7 days. Follicles were subjected to 4 different treatments. Follicles in medium without amino acids and gonadotrophins were assigned as control groups. Follicles in medium with PMSG and without amino acids constituted a positive control whereas the other treatments were test groups. Every 24 h follicle diameters were measured and the media was changed. In the second experiment, the mice were injected daily with 0.2 ml of saline (control) or saline with a mixture of serine and threonine (test) for 5 days. After the last injection, the mice were cervically dislocated and the ovaries were removed and then stained with haematoxylin and eosin. The numbers of activated primordial follicles, primary follicles, preantral follicles, antral follicles and atretic follicles were blind counted in every 7 sections. In culture, neither of the treatments significantly increased the diameters of the follicles over those of the control group. According to the results of the second experiment, the injection of serine/threonine significantly reduced the number of activated primordial follicles entering the primary stage of growth, but after the primary stage the growth rate increased in the amino acid injected animals. Preantral follicle growth beyond the secondary stage was stimulated by amino acid injection and more follicles went through to the antral stage. As the growth rate increased, the number of atretic follicles was also increased by amino acid injection. In the early antral stage, the number of atretic follicles in the test animals was significantly lower, because atresia in the test group occurred mostly in the late antral stage.

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