Related Experiment Video
Updated: Aug 4, 2026
11:31
Isolation of Peritoneum-derived Mast Cells and Their Functional Characterization with Ca2+-imaging and Degranulation Assays
Published on: July 4, 2018
The relationship between histamine secretion and 45calcium uptake by mast cells
The Journal of Physiology
|September 1, 1977
Summary
Mast cells rapidly take up calcium (Ca) upon stimulation, a process linked to histamine release. This calcium uptake is independent of granule discharge and influenced by pH and specific inhibitors.
Area of Science:
- Immunology
- Cell Biology
- Biochemistry
Background:
- Mast cells are key immune cells involved in allergic responses.
- Calcium (Ca) influx is a critical signaling event in mast cell activation.
- Understanding Ca dynamics is crucial for elucidating mast cell degranulation.
Purpose of the Study:
- To investigate the kinetics and characteristics of calcium uptake in stimulated rat mast cells.
- To determine the relationship between calcium uptake, histamine secretion, and cellular metabolism.
- To explore the role of cyclic nucleotides and phosphatidylserine in mast cell activation.
Main Methods:
- Utilized radioactive calcium-45 ((45)Ca) to quantify calcium uptake in rat peritoneal mast cells.
- Stimulated mast cells using antigen-antibody reactions, dextran, concanavalin A, and the Ca ionophore A 23187.
- Assessed histamine secretion and evaluated the effects of metabolic inhibitors (glycolysis, oxidative phosphorylation inhibitors) and signaling molecules (dibutyryl cyclic AMP, theophylline).
Main Results:
- Mast cells exhibited rapid (45)Ca uptake within 1 minute of stimulation, independent of extracellular binding or surface area changes.
- Increased (45)Ca uptake correlated with histamine secretion magnitude and was pH-dependent, with optimal activity at pH 7.5.
- A significant portion of Ca uptake occurred independently of cellular metabolism and granule discharge, unlike histamine secretion.
Conclusions:
- Mast cell stimulation triggers rapid calcium influx that is mechanistically distinct from histamine release.
- Calcium uptake is a metabolic-independent process, while histamine secretion requires intact cellular energy production.
- Modulators like dibutyryl cyclic AMP and theophylline inhibit both calcium uptake and histamine release, suggesting a complex regulatory network.
Related Concept Videos
01:27Feedback Regulation of Calcium Concentration
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
01:16Calmodulin-dependent Signaling
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
01:17Hormones and Bone Tissue
The endocrine system produces and secretes hormones, which interact with the skeletal system. These hormones control bone growth, maintain bone once it is formed, and remodel it.
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
01:21Skeleton and Calcium Homeostasis
Calcium is not only the most abundant mineral in bone but also the most abundant mineral in the human body. Calcium ions are needed for bone mineralization, tooth health, heart rate regulation and strength of contraction, blood coagulation, the contraction of smooth and skeletal muscle cells, and the regulation of nerve impulse conduction. The average calcium level in the blood is about 10 mg/dL. When the body cannot maintain this level, a person will experience hypo or hypercalcemia.