Sıçan Beyninde Vanilloid Resptör Altgrup Tip-1’in Gonodotropin Salgılayan Hormon Nöronlarında Ifade Edilmesi

Abstract

Kapsisum 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 sensitif nöronları tanımlamak için nöroparmakolojik bir araç olarak kullanılmaktadır. Kapsaisin etkisini Vanilloid Reseptör Alt Tür-Tip 1 (VR1) ile gösterir. Kapsaisin, çeşitli beyin bölgelerini etkiler, beyinde vanillod duyarlı nöronların var olduğu çeşitli çalışmalarda bildirilmiştir. Hipotalamusta bulunan VR1 reseptörleri büyük olasılıkla ağrı vücut ısısının düzenlenmesi, besin alımı, metabolik denge vb. diğer önemli fonksiyonlara sahiptir. Bu çalışmada, VR1 reseptörlerinin üreme üzerindeki potansiyel fizyolojik rolünü araştırmayı amaçladık. Bu amaç ile sıçan beyninde VR1 ifade eden Gonodotropin Salgılayan Hormonu (GnRH) nöronlarının dağılımını araştırmak için ikili immünoflöresan tekniğini kullandık. Çoğu VR1 pozitif GnRH nöronu ağırlıklı olarak organ vascualris lamina terminalinde bulunur ve preoptik alan daha az medial septum diyagonal bandında uzanır. VR1'in GnRH nöronlarında ifade edilmesi önemlidir, bu bulgu VR1’in üreme aksında rol oynayabileceğini gösterebilir.

Keywords

• GnRH
• VR-1
• Ko-lokalizasyon

The Expression of Vanilloid Receptor Subtype-1 (VR1) in Gonadotropin-Releasing Hormone in Rat Brain

Abstract

Capsaicine (CAP), a lipophilic vanilloid substance found in Capsicum peppers which produces the sensation of heat, has a prominent excitatory action on primary afferent neurons, and has long been used as a neuropharmacological tool to identify sensitive neurons. CAP shows its effect via Vanilloid Receptor Subtype-1 (VR1). Capsaicin affects a variety of brain regions , the presence of vanillod sensitive neurons in the brain has been reported in several studies. The VR1 receptors present in the hypothalamus most likely have other important functions including regulation of body temperature, food intake, metabolic balance etc. In this study we aimed to investigate potential physiological role of VR1 receptors in reproduction. Fort his purpose we performed dual immunofluorescence staining to explore the distribution of Gonodotropin Releasing Hormone (GnRH) neurons that express VR1 in rat brain. Most VR1 positive GnRH neurons found predominantly in organum vascularis lamina terminalis and preoptic area lesser extend in medial septum diagonal band. 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.

Keywords

• GnRH
• VR1
• Co-Localization

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