Volume regulation in mouse pancreatic islet cells as studied by a new technique of microperifusion

Publisher Website
Google Scholar
Abstract
A new technique was designed to analyse whether pancreatic islet cells are able to regulate their volume in anisotonic media. The projected cell area of individual cells was continuously observed, and the corrcsponding volume calculated during microperifusion with media of diffrent osmolarities. In isotonic medium (317 niosmol) the cell volume was stable during perifusion and decreased by 17 or 25% when the osmolarity was increased (sucrose) to 417 or 517 mosmol. Reducing the medium osmolariti to 285 mosmol resulted in a volume reduction of ahout 7%. No evidence for cell volume regulation was observed in these media. Homever, reducing the medium osmolarity to 262 niosmol induced an immediate and rapid cell swelling of approximately 14% after which the initial cell volume was regained Mithin 9 min. The data suggest that the pancreatic islet cells are equipped with mechanisms for regulatory volume decrease that appear to he actibated when the cell volume is increased above a certain limit.