Sıçan Kemik Defekti Modelinde Ekzenatidin Göz İçi Basıncı Üzerindeki Geçici Etkileri

Öz

Bu çalışma, glukagon benzeri peptid-1 (GLP-1) reseptör agonisti exenatidin, kemik defekti oluşturulan Sprague-Dawley sıçanlarda intraoküler basınç (IOB) üzerine etkisini ve uygulama zamanı ile süresinin bu etkiyi değiştirip değiştirmediğini değerlendirmeyi amaçladı. Sekiz-on haftalık, 200–250 g ağırlığında toplam 36 erkek sıçan, iki kontrol ve dört tedavi grubu olmak üzere altı gruba rastgele ayrıldı. Tedavi gruplarında exenatid, cerrahi öncesi veya sonrası dönemde farklı sürelerde intraperitoneal olarak uygulandı. Tüm hayvanlarda başlangıç IOB ölçümleri yapıldıktan sonra cerrahi olarak kemik defekti oluşturuldu ve yedinci postoperatif günde rebound tonometre ile tekrar IOB ölçümü gerçekleştirildi. IOB ölçümleri, çalışmanın birincil sonucu olmaktan ziyade, deneysel kemik defekti modelinde keşif amaçlı ikincil bir sonuç olarak dahil edilmiştir. Sonuçlara göre yalnızca postoperatif dönemde üç gün exenatid uygulanan grupta IOB’da istatistiksel olarak anlamlı bir değişiklik saptandı (P=0.027). Diğer exenatid uygulama protokollerinde anlamlı bir fark gözlenmedi. Buna karşılık, her iki kontrol grubunda da postoperatif dönemde IOB’da anlamlı düşüşler tespit edildi (plasebo grubu: P=0.023; yalnızca defekt grubu: P=0.026). Bu bulgular, ekzenatidin bazı postoperatif koşullar altında GİB’i geçici olarak etkileyebileceğini ve kontrol gruplarında gözlenen azalmayı kısmen dengeleyebileceğini düşündürmektedir. Ancak olası karıştırıcı faktörler nedeniyle etkinin yönü ve büyüklüğü belirsiz olup, sonuçlar keşifsel nitelikte değerlendirilmelidir.

Anahtar Kelimeler

• Exenatid
• glukagon benzeri peptid-1 agonistleri
• intraoküler basınç
• oküler fizyoloji
• sıçan

Etik Beyan

Bu çalışmada kullanılan hayvanlar daha önce “Glukagon benzeri peptid-1 reseptör agonisti olan eksenatid, sıçanlarda kemik iyileşmesini olumsuz etkileyebilir: histopatolojik, biyokimyasal ve in silico bulgular” başlıklı araştırmada kullanılmıştı. Çalışma protokolü Kastamonu Üniversitesi Deney Hayvanları Yerel Etik Kurulu tarafından onaylanmıştır (onay no: 2025/5).

Transient Effects of Exenatide on Intraocular Pressure in a Rat Bone Defect Model

Öz

This study aimed to evaluate whether the glucagon-like peptide-1 (GLP-1) receptor agonist exenatide influences intraocular pressure (IOP) in Sprague–Dawley rats subjected to a bone defect model, and whether the timing and duration of administration modify this effect. A total of 36 male rats (8–10 weeks old, 200–250 g) were randomly allocated into six groups, including two control groups and four treatment groups receiving exenatide either preoperatively or postoperatively for different durations. Baseline IOP was measured in all animals prior to surgical creation of a bone defect. Exenatide or saline was administered intraperitoneally, and IOP was re-evaluated on postoperative day 7 using a rebound tonometer. IOP measurements were included as an exploratory secondary outcome within the experimental bone defect model rather than the primary endpoint of the study. The results demonstrated a statistically significant change in IOP only in the group receiving exenatide for three days postoperatively (P=0.027), whereas no significant changes were observed in the other treatment groups. In contrast, both control groups exhibited significant postoperative reductions in IOP (placebo group: P=0.023; sham group: P=0.026). These findings suggest that exenatide might transiently influence IOP under certain postoperative conditions, possibly counteracting decreases observed in control groups. However, due to potential confounding factors, the direction and magnitude of this effect remain uncertain and should be considered exploratory.

Anahtar Kelimeler

• Exenatide
• glucagon-like peptide-1 agonists
• intraocular pressure
• ocular physiology
• rat

Etik Beyan

The animals used in this study had been previously utilized in the research entitled “Exenatide, a glucagon-like peptide-1 receptor agonist, may negatively impact bone healing in rats: histopathological, biochemical, and in silico findings.” The study protocol was approved by Kastamonu University Local Ethics Committee for Experimental Animals (approval no: 2025/5).

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