GCaMP6f-expressing chromaffin cells in murine adrenal slices exhibit dynamic spontaneous calcium responses that do not require nerve input

Chromaffin cells of the adrenal medulla exhibit spontaneous action potentials and intracellular Ca2+ responses that, when dissociated in vitro, result in catecholamine secretion. However, spontaneous activity in these cells is nearly abolished when splanchnic nerve input is blocked in vivo. To address this discrepancy, we examined spontaneous Ca2+ responses in chromaffin cells using an intermediate preparation: adrenal slices from transgenic mice expressing the genetically encoded Ca2+ indicator GCaMP6f selectively in these cells. Within this preparation, the three-dimensional structure and extracellular environment surrounding chromaffin cells are retained, as is input from distal splanchnic nerve terminals, which spontaneously release the neurotransmitter acetylcholine. Chromaffin cells within these slices displayed spontaneous Ca2+ responses with frequencies and amplitudes that varied greatly within and between individual cells. However, population averages remained stable, providing..., , # Data from: GCaMP6f-expressing chromaffin cells in murine adrenal slices exhibit dynamic spontaneous calcium responses that do not require nerve input

Dataset DOI: [10.5061/dryad.zpc866tm1](10.5061/dryad.zpc866tm1)

## Description of the data and file structure

We collected spontaneous calcium fluorescence transients from chromaffin cells within adrenal slices from mice expressing the calcium indicator GCaMP6f. To determine which mechanisms contributed to this spontaneous activity, we conducted several experiments in which we blocked various ion channels and receptors while recording calcium activity in six one-minute videos spaced five minutes apart. The first three videos were recorded prior to (pre-), and the last three videos after (post-), perfusing the blocker of choice. The drugs we used included EGTA to deplete extracellular calcium, cyclopiazonic acid (CPA) to deplete intracellular calcium stores, nifedipine (NIF) to selectively block L-type voltage-gated calcium channels, t...,