Related Experiment Videos
Swelling-induced catecholamine secretion recorded from single chromaffin cells
1Abteilung Membranbiophysik, Max-Planck-Institut für Biophysikalische Chemie, Göttingen, Germany.
Pflugers Archiv : European Journal of Physiology
|December 1, 1995
Summary
Osmotic stress triggers catecholamine release from adrenal cells via calcium-dependent exocytosis. Cell swelling activates a chloride current, leading to depolarization and calcium influx, thus modulating secretion.
Area of Science:
- Neuroscience
- Cell Biology
- Endocrinology
Background:
- Adrenal chromaffin cells are crucial for catecholamine release.
- Osmotic stress is a potential regulator of cellular secretion.
Purpose of the Study:
- To investigate the mechanism of osmotically induced catecholamine secretion.
- To elucidate the role of intracellular calcium and cell volume changes in this process.
Main Methods:
- Patch-clamp electrophysiology
- Electrochemical detection of secretion
- Fura-2 measurements of intracellular free calcium concentration ([Ca2+]i)
Main Results:
- Osmotically induced catecholamine release is exocytotic and calcium-dependent.
- Cell swelling activates a volume-activated current, primarily carrying chloride ions.
- This current causes membrane depolarization, enhancing voltage-gated calcium influx.
Conclusions:
- Cell volume changes are mechanistically linked to catecholamine secretion.
- Volume-activated currents play a significant role in regulating adrenal chromaffin cell secretory activity.