Sıçan midesinde leptin ekspresyonunun immunohistokimyasal olarak gösterilmesi

iriş: Leptin, ob gen tarafından kodlanan 16-kDa ağırlığında bir moleküldür. İlk olarak yağ dokusunda tanımlanan leptinin son zamanlarda vücutta çeşitli dokularda da ifade edildiği gözlenmiştir. Çeşitli çalışmalar leptinin midede de fonksiyon gösterebileceğini önermektedir. Bu çalışmada, sıçan mide dokusunda leptinin immünohistokimyasal dağılımını ve ifadesini araştırmak amaçlanmıştır. Gereç ve Yöntem: Bu çalışmada 190-210 gr ağırlığında erkek sıçanlar kullanılmıştır. Işık mikroskopik incelemeler için Wistar albino 5 sıçan anastezi edilmiş ve heparinize edilip fosfat tamponlu % 4 paraformaldehit ile intrakardiyak perfüze edilmiştir. Rutin histolojik takip uygulanan mide dokusu daha sonra 5 µm kalınlıkta kesilip Leptin immunohistokimyasal boyaması yapılmıştır. Bulgular: Midenin fundus bölgesinde leptin (+) boyanan gerek esas hücre, gerekse pariyetal hücre sayısı korpus bölgesine oranla anlamlı derecede artmış bulundu. Korpustaki leptin (+) hücreler kıyaslandığında esas hücre ve pariyetal hücre sayıları arasında anlamlı bir fark saptanmadı; diğer taraftan fundustaki leptin (+) esas hücre sayısının leptin (+) pariyetal hücre sayısından anlamlı şekilde fazla olduğu gözlendi. Ayrıca, myenterik pleksusta boyanma gözlemlendi. Sonuç: Bu çalışmada diğer çalışmalardan farklı olarak temel olarak gastrointestinal hareketleri kontrol eden myenterik pleksusda da leptinin varlığı gösterilmektedir. Leptinin sinerjistik etki gösterip beslenmenin düzenlenmesinde kısa süreli regülasyon ve/veya uzun süreli regülasyonda rol oynayabileceği gösterilmektedir.

Immunohistochemical demonstration of leptin expression in the rat stomach

Introduction: Leptin is a 16-kDA-protein molecule, expressed by the ob gene. It has first been found in the adipose tissue and several tissues in the body have recently been described to express leptin. Various reports have suggested that leptin can also involve in stomach functions. This study was focused on the expression and distribution of leptin in rat stomach using immunohistochemistry. Material and Methods: The study was conducted on male rats weighing 190–210 g. For light microscopic examination, 5 Wistar albino rats were anaesthetized and perfused transcardiacally with heparinised saline followed by %4 paraformaldehyde in phosphate buffer. Leptin immunohistochemistry was performed on stomach tissues preprocessed for routine histological examination at 5 µm slices. Results: The number of leptin (+) principal cells and parietal cells in the fundus of stomach was significantly higher than the corpus. The comparison of leptin (+) cell number within the corpus revealed no significant difference between the number of principal cells and parietal cells; however statistical analysis within the fundus showed that leptin (+) principal cell number was significantly higher than leptin (+) parietal cell number. Moreover, marked stain was observed in the myenteric plexus. Conclusion: Differing from the available studies, data obtained in the current study show that leptin is expressed in the myenteric plexus controlling the gastrointestinal peristaltism. It has been postulated that leptin may participate synergistically in the short- and/or long-term regulation of alimentary functions.

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