Autocrine/paracrine modulation of calcium channels in bovine chromaffin cells

  title={Autocrine/paracrine modulation of calcium channels in bovine chromaffin cells},
  author={Jes{\'u}s Miguel Hern{\'a}ndez-Guijo and Luis Gand{\'i}a and Baldomero Lara and A. G. Garcı́a},
  journal={Pfl{\"u}gers Archiv},
Abstract Applying 10-s pulses of 10 mM Ba2+ to resting or K+-depolarized (70 mM) bovine adrenal chromaffin cells superfused with a nominal 0Ca2+ solution produced a large catecholamine secretory peak. In contrast, pulses of 10 mM Sr2+ or Ca2+ did not induce secretion from polarized resting cells, and induced smaller and narrower secretory peaks from depolarized cells; the areas of the secretory peaks from depolarized cells were 1.87, 3.06 and 27.4 nA s, respectively, for Ca2+, Sr2+ and Ba2… 
Modulation by endogenously released ATP and opioids of chromaffin cell calcium channels in mouse adrenal slices.
Results suggest that in the intact adrenal tissue a tonic inhibition of I(Ca) exists, mediated by purinergic and opiate receptors, and this inhibition was partially voltage independent and insensitive to prepulse facilitation.
Calcium signaling and exocytosis in adrenal chromaffin cells.
It is proposed that chromaffin cells have developed functional triads that are formed by calcium channels, the ER, and the mitochondria and locally control the [Ca2+]c that regulate the early and late steps of exocytosis.
Extracellular ATP regulates exocytosis by inhibiting multiple Ca2+ channel types in bovine chromaffin cells
Results lend support to the hypothesis of autocrine modulation of exocytosis by endogenously released ATP acting on P2y-purinoceptors to inhibit ICa, and suggest feedback regulation of the rate of release will be a complex function of the occupancy of those receptors and of the electrical and secretory activity of the cell.
L- and T-type voltage-gated Ca2+ channels in human granulosa cells: functional characterization and cholinergic regulation.
Using the whole-cell configuration of the patch-clamp technique, two types of ionic currents through voltage-dependent Ca2+ channels in human granulosa cells are characterized, suggesting a possible role of these channels in the cholinergic regulation of human ovarian functions.
Down-Modulation of Ca2+ Channels by Endogenously Released ATP and Opioids: from the Isolated Chromaffin Cell to the Slice of Adrenal Medullae
The well-established data on the modulation of voltage-dependent Ca2+ channels described in isolated chromaffin cells by the laboratory and others and the new results obtained in a more physiological preparation: freshly isolated slices of mouse adrenal medullae are summarized.
Reconstitution of neurotransmission by determining communication between differentiated PC12 pheochromocytoma and HEL 92.1.7 erythroleukemia cells
It is demonstrated that a random distribution between effector and target cells is sufficient to allow communication between cells in a manner similar to extrasynaptic transmission, and suggests that, as in neurons, P/Q- and N-type Ca2+ channels mediate the release of neurotransmitters acting on HEL cells.
Roles of Na+, Ca2+, and K+ channels in the generation of repetitive firing and rhythmic bursting in adrenal chromaffin cells
This review aims to give a rationale to the role of the many ion channel types regulating CC excitability, and describe their functional properties and analyze how they contribute to pacemaking, AP shape, and burst waveforms.


Human adrenal chromaffin cell calcium channels: drastic current facilitation in cell clusters, but not in isolated cells
It is concluded that human adrenal chromaffin cells mostly express P/Q-types of voltage-dependent Ca2+ channels (60%).
Regulation of the secretory response in bovine chromaffin cells.
The findings suggest that the secretory response of chromaffin cells may be modulated by rapid desensitization of the nicotinic receptor and a secretion-dependent suppression of the Ca2+ current.
The mechanism of calcium channel facilitation in bovine chromaffin cells.
The experiments suggest that facilitation by prepulses of whole‐cell current through Ca2+ channels is due to the suppression of an autoinhibitory autocrine loop present in bovine chromaffin cells.
ATP modulation of calcium channels in chromaffin cells.
The ATP, co‐released with catecholamines in the intact adrenal gland, may inhibit the secretory process by down‐regulating the Ca2+ channel via a P2‐type purinergic receptor coupled to a PTX‐sensitive G protein.
Facilitation of calcium influx by propylene glycol through the voltage-dependent calcium channels in PC12 cells.
  • T. Hattori, H. Maehashi
  • Biology, Chemistry
    Research communications in molecular pathology and pharmacology
  • 1999
The results obtained suggested that the Ca2+ influx through the L- and N-type Ca1+ channels are involved in the PG-induced [Ca2+]i rise, and which types participate in it.
Functional organization of chromaffin cells and cholinergic synaptic transmission in rat adrenal medulla.
Electrical properties of chromaffin cells in situ were in agreement with previous reports on cultured cells, and there were multiple peaks in the EPSC amplitude histograms in low-[Ca2+] saline, which probably represents the quantal size of the synapse.
Sodium and calcium channels in bovine chromaffin cells
Inward currents in chromaffin cells were studied with the patch‐clamp technique and current recordings were obtained in cell‐attached, outside‐out and whole‐cell recording configurations.
Ca2+-channel-dependent and -independent inhibition of exocytosis by extracellular ATP in voltage-clamped rat adrenal chromaffin cells
The data show that extracellular ATP inhibits exocytosis via inhibition of ICa by activation of a pertussis-toxin-sensitive G-protein linked to P2Y receptors, and suggest that ATP activates another pathway, which is also G- protein dependent and accounts for the majority of the inhibitory effect of ATP on exocyTosis.