Two independently regulated secretory pathways in mast cells.
We review here evidence that mast cells independently secrete large and small vesicles. Release of small vesicles is triggered by Ca2+. Combining capacitance measurements and flash photolysis of caged Ca2+, we demonstrate Ca-triggered exocytosis that is kinetically identical to the release of dense-core peptidergic vesicles from pituitary melanotrophs. It is suggested that the secretory pathway used for hormone secretion in neuroendocrine cells is also active in mast cells and eosinophils. The nature of the mediator thus secreted is unknown.
Kirillova
J
J
Department of Physiology and Biophysics, University of Washington, Seattle 98195.
Thomas
P
P
Almers
W
W
D000818:Animals; D002118:Calcium / Q000502:physiology*; D007700:Kinetics; D008407:Mast Cells / Q000378:metabolism*; D009074:Melanocyte-Stimulating Hormones / Q000378:metabolism; D008854:Microscopy, Electron; D010902:Pituitary Gland / Q000166:cytology / Q000378:metabolism; D051381:Rats
D009074:Melanocyte-Stimulating Hormones; D002118:Calcium