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

Amaç Kapsikum biberlerinde bulunan ve ısı hissini üretenlipofilik bir vanilloid madde olan Kapsaisin (KAP),birincil afferent nöronlar üzerinde belirgin bir uyarıcıetkiye sahiptir ve uzun zamandan beri hassas nöron ları tanımlamak için nöroparmakolojik bir araç olarakkullanılmaktadır. Kapsaisin etkisini Vanilloid ReseptörAlt Türü-1 (VR1) ile gösterir. Kapsaisin, çeşitli beyinbölgelerini etkiler, beyinde vanillod duyarlı nöronlarınvar olduğu çeşitli çalışmalarda bildirilmiştir. Hipotala musta bulunan VR1 reseptörleri büyük olasılıkla ağrıvücut ısısının düzenlenmesi, besin alımı, metabolikdenge 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 tekniğinikullandık.Bulgular Çoğu VR1 pozitif GnRH nöronları ağırlıklı olarak or ganum vaskülozum lamina terminalis ve preoptikalanda, daha az olarak ise medial septum diyagonalbandında gözlendi. Sonuç VR1'in GnRH nöronlarında ifade edilmesi önemlidir,bu bulgu VR1’in üreme aksında rol oynayabileceğinigösterebilir.

THE EXPRESSION OF VANILLOID RECEPTORSUBTYPE-1 (VR1) IN GONADOTROPIN-RELEASINGHORMONE IN RAT BRAIN

Objective Capsaicin (CAP), a lipophilic vanilloid substancefound in Capsicum peppers which produces the sen sation of heat, has a prominent excitatory action onprimary afferent neurons, and has long been usedas a neuropharmacological tool to identify sensitiveneurons. Capsaicin shows its effect via Vanilloid Re ceptor Subtype-1 (VR1). Capsaicin affects a varietyof brain regions, the presence of vanillod sensitiveneurons in the brain has been reported in several stu dies. The VR1 receptors present in the hypothalamusmost likely have other important functions includingregulation of body temperature, food intake, metabo lic balance etc. In this study we aimed to investigatepotential 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 thatexpress VR1 in rat brain.Results Most VR1 positive GnRH neurons found predomi nantly in organum vasculosum lamina terminalis andpreoptic area lesser extend in medial septum diago nal band.Discussion The findings that VR1 is expressed in GnRH neuronsis of great importance, it can be speculated that VR1may have a role in reproductive axis.

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