Related Experiment Video
Updated: Jun 23, 2026
12:33
A Method for Mouse Pancreatic Islet Isolation and Intracellular cAMP Determination
Published on: June 25, 2014
Inhibitory effects of leptin on pancreatic alpha-cell function
Eva Tudurí1, Laura Marroquí, Sergi Soriano
1Instituto de Bioingeniería, Universidad Miguel Hernandez, Elche, Spain.
Diabetes
|April 30, 2009
Summary
Leptin, a hormone from fat cells, suppresses glucagon secretion by inhibiting alpha-cell electrical activity and calcium signaling. This reveals a new role for leptin in adipo-insular communication and glucose homeostasis.
Area of Science:
- Endocrinology
- Cell Biology
- Metabolism
Background:
- Leptin regulates food intake, energy balance, and glucose homeostasis.
- Leptin influences pancreatic beta-cells, affecting insulin secretion.
- The role of leptin in pancreatic alpha-cell function remains largely uncharacterized.
Purpose of the Study:
- To investigate the functional interaction between leptin and pancreatic alpha-cells.
- To determine if leptin affects glucagon secretion.
Main Methods:
- Detection of leptin receptors (ObR) using RT-PCR, Western blot, and immunocytochemistry.
- Analysis of alpha-cell electrical activity and calcium signaling via patch-clamp and confocal microscopy.
- Assessment of glucagon secretion using fluorescence methods and radioimmunoassay.
Main Results:
- Leptin receptors (ObR isoforms, including ObRb) were detected in alpha-cells.
- Leptin hyperpolarized alpha-cells, suppressed electrical activity, and inhibited calcium signaling.
- Leptin reduced glucagon secretion from islets, an effect mediated by the phosphatidylinositol 3-kinase pathway.
Conclusions:
- Leptin directly inhibits alpha-cell function.
- Alpha-cells are involved in adipo-insular communication, linking fat-derived signals to glucose regulation.
More Related Videos
07:44Surgical Injury to the Mouse Pancreas through Ligation of the Pancreatic Duct as a Model for Endocrine and Exocrine Reprogramming and Proliferation
Published on: August 7, 2015
11:24Lentiviral Mediated Gene Silencing in Human Pseudoislet Prepared in Low Attachment Plates
Published on: May 14, 2019
Related Concept Videos
01:27Glucose Homeostasis: Pancreatic Islets and Insulin Secretion
The pancreatic islets comprising only 1%-2% of the volume are highly vascularized and innervated mini-organs. They contain five endocrine cell types, including β cells that secrete insulin, which is synthesized as a single polypeptide chain, preproinsulin, processed to proinsulin, and finally to insulin and C-peptide. This process is complex and regulated, involving the Golgi complex, the endoplasmic reticulum, and the secretory granules of the β cell.
Insulin and C-peptide are co-secreted in...
Insulin and C-peptide are co-secreted in...
01:16Hormones Regulating Blood Glucose
Insulin is released by beta cells of the pancreas when blood glucose levels are high. It facilitates glucose absorption and utilization in insulin-dependent cells with insulin receptors on their plasma membranes. Insulin promotes glucose uptake by increasing the number of glucose transport proteins in the cell membrane, allowing glucose to enter the cell. As a result, glucose utilization and ATP production are enhanced.
In addition to accelerating glucose uptake and utilization, insulin has...
In addition to accelerating glucose uptake and utilization, insulin has...
01:16Cells and Secretions of the Pancreas
The pancreas, a vital organ within the abdominal cavity, plays dual roles in the digestive and endocrine systems, collaborating with exocrine and endocrine cells to maintain optimal digestion and blood sugar levels.
Exocrine function is carried out by acinar cells, organized into clusters known as acini. These cells contribute to digestion by releasing substantial quantities of enzyme-rich, alkaline digestive juices.
Concurrently, the dispersed clusters of endocrine cells throughout the...
Exocrine function is carried out by acinar cells, organized into clusters known as acini. These cells contribute to digestion by releasing substantial quantities of enzyme-rich, alkaline digestive juices.
Concurrently, the dispersed clusters of endocrine cells throughout the...
01:58Cell Specific Gene Expression
Multicellular organisms contain a variety of structurally and functionally distinct cell types, but the DNA in all the cells originated from the same parent cells. The differences in the cells can be attributed to the differential gene expression. Liver cells, whose functions include detoxification of blood, production of bile to metabolize fats, and synthesis of proteins essential for metabolism, must express a specific set of genes to perform their functions. Gene expression also varies with...
01:24Type II Diabetes II: Pathophysiology
PathophysiologyType 2 diabetes mellitus (T2DM ) is a chronic metabolic disorder characterized by insulin resistance and progressive pancreatic β-cell dysfunction, leading to impaired glucose homeostasis. It results from interactions among genetic predisposition, environmental factors, and metabolic stressors, such as overnutrition and a sedentary lifestyle.Insulin Resistance and Glucose DysregulationEarly T2DM involves insulin resistance in skeletal muscle, adipose tissue, and the liver.
01:30Regulation of Food Intake
Short-term regulation of food intake primarily involves neural signals from the gastrointestinal (GI) tract, blood nutrient levels, and GI tract hormones. Communication between the gut and brain via vagal nerve fibers plays a significant role in evaluating the contents of the gut. Clinical studies have shown that protein ingestion produces a more prolonged response in these nerve fibers compared to an equivalent amount of glucose. Additionally, the activation of stretch receptors caused by GI...