Low Frequency Stimulation of Mouse Adrenal Slices Reveals a Clathrin‐Independent, Protein Kinase C‐Mediated Endocytic Mechanism

摘要: Evidence suggests that chromaffin cells employ separate mechanisms for evoked endocytosis and granule recycling when stimulated at basal (∼0.5 Hz) stress-activated (∼15 rates. Previous studies have focused mainly on elucidating the cellular responsible membrane under conditions similar to state indicate a clathrin/dephosphin-mediated retrieval via coated pits. However, mechanism internalisation stimulus intensity remains largely unexplored. We electrically in adrenal tissue slices sympathetic firing rate measured cell capacitance perforated voltage clamp configuration. A new method separation of non-secretory from secretory signals is presented. Simultaneous catecholamine release was electrochemically isolate exocytic endocytic components responses. Using this approach we demonstrate patterns mimic input results rapid graded retrieval. show block calcium-mediated protein phosphatase 2B, common step clathrin-mediated processes, did not alter elicited levels. further blocked with clathrin/dephosphin-disrupting peptide (PP-19) found be 15 Hz stimulation but complete indistinguishable control 0.5 stimulation. Lastly, pharmacological treatments conventional isoforms kinase C (cPKC) are required Hz-evoked mechanism. From these data conclude unlike stress conditions, activity clathrin-independent mediated through PKC.