Electrophysiology of pancreatic beta cells: a comprehensive review of ion channel function, electrical activity, and secretory mechanisms

Öz

Pancreatic β-cells play a crucial role in maintaining glucose homeostasis through the regulation of insulin secre- tion. The electrophysiological properties of these cells, including ion channel function, electrical activity, and secretory mechanisms, are essential for their proper physiological function. In this comprehensive review, we provide an in-depth analysis of the electrophysiology of pancreatic β-cells. We discuss the various ion channels involved in the generation and modulation of electrical signals, such as voltage-gated ion channels, ATP-sensitive and delayed rectifier potassium ion channels, calcium ion channels, chloride channels and transient receptor poten- tial channels. Additionally, we examine the intricate interplay between intracellular calcium dynamics and insulin release. Furthermore, we explore the physiological and pathological factors that influence the electrophysiology of β-cells. A comprehensive understanding of the electrophysiological mechanisms governing pancreatic beta cell function is crucial for elucidating the pathogenesis of diabetes mellitus and developing novel therapeutic strategies.

Anahtar Kelimeler

• pancreatic beta cell
• insulin
• electrophysiology
• KATP channels
• BK channels
• TRPM channels

Pankreas Beta Hücrelerinin Elektrofizyolojisi: İyon Kanal Fonksiyonları, Elektriksel Aktivite ve Sekresyon Mekanizmalarının Kapsamlı Bir Derlemesi

Öz

Pankreatik β-hücreler, insülin salınımının düzenlenmesi yoluyla glukoz homeostazının korunmasında hayati bir rol oynar. Bu hücrelerin iyon kanalı fonksiyonu, elektriksel aktivite ve sekresyon mekanizmaları gibi elektrofizyolojik özellikleri, fizyolojik görevlerini sağlıklı bir şekilde yerine getirebilmeleri açısından kritik öneme sahiptir. Bu kapsamlı derlemede, pankreatik β-hücrelerin elektrofizyolojisi ayrıntılı olarak ele alınmaktadır. Elektriksel sinyal- lerin oluşumu ve modülasyonunda rol oynayan voltaj kapılı iyon kanalları, ATP'ye duyarlı ve gecikmeli rektifiye potasyum kanalları, kalsiyum iyon kanalları, klor kanalları ve geçici reseptör potansiyel (TRP) kanalları gibi çeşitli iyon kanalları tartışılmıştır. Ayrıca, hücre içi kalsiyum dinamiği ile insülin salınımı arasındaki karmaşık etkileşim incelenmiştir. Bunun yanı sıra, β-hücre elektrofizyolojisini etkileyen fizyolojik ve patolojik faktörler de gözden geçirilmiştir. Pankreatik beta hücre fonksiyonlarını yöneten elektrofizyolojik mekanizmaların kapsamlı bir şekilde anlaşılması, diyabetes mellitus patogenezinin aydınlatılması ve yeni tedavi stratejilerinin geliştirilmesi açısından büyük önem taşımaktadır.

Anahtar Kelimeler

• pankreatik beta hücreleri
• insülin
• elektrofizyoloji
• KATP kanalları
• BK kanalları
• TRPM kanalları

Kaynakça

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