THE EXPRESSION OF VANILLOID RECEPTOR SUBTYPE-1 (VR1) IN GONADOTROPIN-RELEASING HORMONE IN RAT BRAIN

Objective Capsaicin (CAP), a lipophilic vanilloid substance found in Capsicum peppers which produces the sen sation of heat, has a prominent excitatory action on primary afferent neurons, and has long been used as a neuropharmacological tool to identify sensitive neurons. Capsaicin shows its effect via Vanilloid Re ceptor Subtype-1 (VR1). Capsaicin affects a variety of brain regions, the presence of vanillod sensitive neurons in the brain has been reported in several stu dies. The VR1 receptors present in the hypothalamus most likely have other important functions including regulation of body temperature, food intake, metabo lic balance etc. In this study we aimed to investigate potential physiological role of VR1 receptors in repro duction. Material and Methods Fort his purpose we performed dual immunofluores cence staining to explore the distribution of Gono dotropin Releasing Hormone (GnRH) neurons that express VR1 in rat brain. Results Most VR1 positive GnRH neurons found predomi nantly in organum vasculosum lamina terminalis and preoptic area lesser extend in medial septum diago nal band. Discussion The findings that VR1 is expressed in GnRH neurons is of great importance, it can be speculated that VR1 may have a role in reproductive axis.

SIÇAN BEYNİNDE VANİLLOİD RESPTÖR ALTGRUP TİP-1’İN GONODOTROPİN SALGILAYAN HORMON NÖRONLARINDA İFADE EDİLMESİ

Amaç Kapsikum biberlerinde bulunan ve ısı hissini üreten lipofilik bir vanilloid madde olan Kapsaisin (KAP), birincil afferent nöronlar üzerinde belirgin bir uyarıcı etkiye sahiptir ve uzun zamandan beri hassas nöron ları tanımlamak için nöroparmakolojik bir araç olarak kullanılmaktadır. Kapsaisin etkisini Vanilloid Reseptör Alt Türü-1 (VR1) ile gösterir. Kapsaisin, çeşitli beyin bölgelerini etkiler, beyinde vanillod duyarlı nöronların var olduğu çeşitli çalışmalarda bildirilmiştir. Hipotala musta bulunan VR1 reseptörleri büyük olasılıkla ağrı vücut ısısının düzenlenmesi, besin alımı, metabolik denge vb. diğer önemli fonksiyonlara sahiptir. Bu ça lışmada, VR1 reseptörlerinin üreme üzerindeki potan siyel fizyolojik rolünü araştırmayı amaçladık. Gereç ve Yöntem Bu amaç ile sıçan beyninde VR1 ifade eden Gonodot ropin Salgılayan Hormonu (GnRH) nöronlarının da ğılımını araştırmak için ikili immünoflöresan tekniğini kullandık. Bulgular Çoğu VR1 pozitif GnRH nöronları ağırlıklı olarak or ganum vaskülozum lamina terminalis ve preoptik alanda, daha az olarak ise medial septum diyagonal bandında gözlendi. Sonuç VR1'in GnRH nöronlarında ifade edilmesi önemlidir, bu bulgu VR1’in üreme aksında rol oynayabileceğini gösterebilir.

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