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Journals / Genel Tıp Dergisi / 2005 / Cilt: 15 - Sayı: 2

Orexins (hipocretins): Novel target molecules in obesity treatment

Oreksinler (hipokretinler): Obezite tedavisinde yeni hedef moleküller

Hülya GÜLTEKİN
SERKAN ŞAHİN
Pages
85–90
DOI
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Conclusion: Except of feeding behavior, several functions are affected by orexins such as energy homeostasis, sleep-wake cycle, drinking, nociception, cardiovascular and neurohumeral process.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:Objective: Orexin A and orexin B are two peptides derived from proteolysis of a 130 amino acid precursor prepro-orexin.
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Key Findings & Data:Main findings: Immunoreactive fibers of orexins are present widespread in brain and two receptors of orexins, OX1 and OX2, are described so far.
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Conclusion & Impact:Conclusion: Except of feeding behavior, several functions are affected by orexins such as energy homeostasis, sleep-wake cycle, drinking, nociception, cardiovascular and neurohumeral process.
🔬Design:Review & Systematic Survey
📍Scope:Comprehensive Sample
⚙️Variables:Nöropeptitler · Narkolepsi · İştah

Abstract

Objective: Orexin A and orexin B are two peptides derived from proteolysis of a 130 amino acid precursor prepro-orexin. The aim of this review was to summarize role of these recently described neurotransmitters in regulation of appetite and other functions which they contribute to. Main findings: Immunoreactive fibers of orexins are present widespread in brain and two receptors of orexins, OX1 and OX2, are described so far. Orexin-A is equipotent at OX1 and OX2 receptors, whilst orexin-B displays 10 fold selectivity for OX2 receptor. Orexin-A and orexin-B are demonstrated in hypothalamus and other regions of central nervous system and also in adrenal gland and small intestine. OX1 receptor is defined mainly in the hypothalamus, locus coeruleus and spinal cord. OX2 receptor is presented in hypothalamus, cortex, spinal cord and a few brain nuclei. Conclusion: Except of feeding behavior, several functions are affected by orexins such as energy homeostasis, sleep-wake cycle, drinking, nociception, cardiovascular and neurohumeral process.

Özet

Amaç: Oreksin-A ve oreksin-B, 130 amino asidli prekürsör prepro-oreksinin proteolizi sonucu oluşan iki peptiddir. Bu derlemenin amacı, nispeten yeni tanımlanan bu nörotransmitterlerin iştahın düzenlenmesindeki rollerinin ve katkıda bulundukları diğer işlevlerin özetlenmesidir. Ana bulgular: İmmunoreaktif lifleri beyinde geniş ölçüde dağılan oreksinlerin şimdiye kadar iki reseptörü, OX1 ve OX2, tanımlanmıştır. Oreksin-A, OX1 ve OX2 reseptörlerine eşit etkinlikte, oreksin-B ise OX2 reseptörüne yaklaşık 10 kat daha selektiftir. Oreksin-A ve oreksin-B hipotalamusta ve santral sinir sisteminin diğer bölgelerinde, adrenal bezde ve ince barsakta gösterilmiştir. OX1 reseptörü esas olarak hipotalamus, locus coeruleus ve omurilikte tanımlanmıştır. OX2 reseptörü ise hipotalamus, korteks, omurilik ve bazı beyin nukleuslarında gösterilmiştir. Sonuç: Oreksinler, beslenme davranışı dışında, enerji dengesi, uyku-uyanıklık döngüsü, susama, ağrı, kardiyovasküler ve nörohormonal çeşitli işlevlere katılmaktadır.

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Cite This Article

GÜLTEKİN, H., ŞAHİN, S. (2005). Orexins (hipocretins): Novel target molecules in obesity treatment. Genel Tıp Dergisi, Cilt: 15 - Sayı: 2, 85–90. https://ajindex.com/articles/224942

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