Yetişkin Erkek Suriye Hamsterleri (Mesocricetus auratus), Serum Melatonin ve Leptin Seviyelerinde ve Ayrıca GnRH, GnIH ve Kisspeptin Genlerinin Ekspresyonunda Günlük Ritim Gösterir

Nöroendokrin ve üreme sistemi beyin ve gonadlar arasındaki kompleks nöronal ve hormonal etkileşim ile kontrol edilmektedir. GnRH, GnIH ve Kisspeptin bu ilişkide önemli nöropeptidlerdir. Bu nöropeptitlerin mevsimsel olarak değişimleri fotoperiyodik hayvanlarda gösterilmiş olsa da, günlük ritimlerinde net bir bilgi bulunmamaktadır. Ayrıca, melatonin ve leptin hormonları da üremenin düzenlenmesinde önemli iki hormondur. Çalışmamızda günlük melatonin ve leptin ritimlerinin GnIH, GnRH ve kisspeptin gen ekspresyonları ve protein salınımları ile ilişkisi incelendi. Yetişkin erkek Suriye hamsterleri uzun fotoperiyotta tutuldular. 30 günlük deney süresinin sonunda her gruptan günün 04:00, 12:00, 20:00 ve 00:00 saatlerinde kan ve doku örnekleri alındı. Melatonin ve leptin hormonlarının günlük ritimleri ELISA ile belirlendi. Real Time PCR yöntemiyle GnRH, GnIH, kisspeptin ve β-aktin genlerine karşılık gelen primerler kullanılarak bu genlerin kantitatif analizi yapıldı. Protein ifadeleri Western Blot tekniği ile belirlendi. Serum melatonin ve leptin seviyeleri ters yönlü ritmik ilişki gösterdi. Karanlıkta leptin düzeyi düşük, melatonin düzeyi yüksek bulundu. GnIH, GnRH ve Kisspeptin mRNA ifadelerinde ve protein salınımlarında günlük ritimler gözlendi. Sonuç olarak bulgularımız, melatonin, leptin, GnIH, GnRH ve kisspeptin arasındaki ilişkilerin üreme üzerinde olmayabileceği ancak metabolik olabileceğini düşündürmektedir

Anahtar Kelimeler:

Gen ekspresyonu, GnIH, GnRH, Kisspeptin, Leptin, Melatonin

Adult Male Syrian Hamsters (Mesocricetus auratus) Exhibit Daily Oscillations in Their Serum Levels of Melatonin and Leptin As Well As in the Expression of the GnRH, GnIH, and Kisspeptin Genes

Keywords:

Gene expression, GnIH, GnRH, Kisspeptin, Leptin, Melatonin,

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