Faculty Opinions recommendation of Differential Co-release of Two Neurotransmitters from a Vesicle Fusion Pore in Mammalian Adrenal Chromaffin Cells.

2019 ◽  
Author(s):  
Pascal S Kaeser
Keyword(s):  
Chromaffin Cells ◽  
Vesicle Fusion ◽  
Fusion Pore ◽  
Adrenal Chromaffin Cells ◽  
Adrenal Chromaffin

scholarly journals Differential Co-release of Two Neurotransmitters from a Vesicle Fusion Pore in Mammalian Adrenal Chromaffin Cells

Neuron ◽  
2019 ◽  
Vol 102 (1) ◽  
pp. 173-183.e4 ◽  
Author(s):  
Quanfeng Zhang ◽  
Bin Liu ◽  
Qihui Wu ◽  
Bing Liu ◽  
Yinglin Li ◽  
...  
Keyword(s):  
Chromaffin Cells ◽  
Vesicle Fusion ◽  
Fusion Pore ◽  
Adrenal Chromaffin Cells ◽  
Adrenal Chromaffin

Control of membrane fusion dynamics during regulated exocytosis

2001 ◽  
Vol 29 (4) ◽  
pp. 467-472 ◽  
Author(s):  
R. D. Burgoyne ◽  
R. J. Fisher ◽  
M. E. Graham ◽  
L. P. Haynes ◽  
A. Morgan
Keyword(s):  
Membrane Fusion ◽  
Chromaffin Cells ◽  
Fusion Pore ◽  
General Strategy ◽  
Adrenal Chromaffin Cells ◽  
Regulated Exocytosis ◽  
Cysteine String Protein ◽  
Adrenal Chromaffin ◽  
Pore Dynamics

The study of regulated exocytosis uniquely allows the direct measurement of intracellular membrane fusion events in real time. We have exploited this to examine factors that regulate not only the extent but also the dynamics of single fusion/release events. The general strategy used has been to assess exocytosis in transiently transfected PC12 or adrenal chromaffin cells. We aimed to design mutant constructs based on in vitro biochemistry, in some cases informed by knowledge of protein structure. Using this approach we have demonstrated an inhibitory role for the putative Rab3 effector Noc2 that requires interaction with Rab3. Using carbon-fibre amperometry on adrenal chromaffin cells, we have demonstrated regulation of the kinetics of single granule release events consistent with changes in fusion pore dynamics and switches between full fusion and ‘kiss-and-run’ fusion. These studies have demonstrated a late role for cysteine string protein in exocytosis. In addition, they have focused attention on a key role for Munc18 in the regulation of post-fusion events that affect fusion pore dynamics.

scholarly journals Synaptotagmin-7 endows a population of chromaffin cell vesicles with enhanced calcium sensing and delayed content release properties

2019 ◽  
Author(s):  
M Bendahmane ◽  
AJB Kreutzberger ◽  
A Chapman-Morales ◽  
J Philippe ◽  
N Schenk ◽  
...  
Keyword(s):  
Chromaffin Cells ◽  
Physiological Role ◽  
Calcium Sensitivity ◽  
Vesicle Fusion ◽  
Adrenal Chromaffin Cells ◽  
Supported Bilayers ◽  
Calcium Sensors ◽  
Calcium Sensing ◽  
Synaptotagmin 1 ◽  
Adrenal Chromaffin

Synaptotagmin-7 (Syt-7) is one of two major calcium sensors for exocytosis in adrenal chromaffin cells, the other being synaptotagmin-1 (Syt-1). Despite its undoubted importance, questions remain as to the functional and physiological role of Syt-7 in secretion. We examined this issue using two distinct preparations - mouse chromaffin cells lacking endogenous Syt-7 (KO cells) and a reconstituted system employing cell-derived vesicles expressing either Syt-7 or Syt-1. First, we report using immunofluorescence that Syt-7 exhibits a punctate intracellular distribution consistent with its sorting to organelles, including dense core vesicles. We also find that the likelihood of vesicle fusion in KO cells is markedly lower than in WT cells. When fusion does occur, cargoes are discharged more rapidly when only Syt-1 is available to facilitate release. A distinctive characteristic of KO cells is that secretion runs down after prolonged cholinergic stimulation. In contrast, exocytosis persists in WT cells even with extended exposure to acetylcholine, suggesting a key role for Syt-7 in sustaining the secretory response. To determine the extent to which the aforementioned results are attributable purely to Syt-7, vesicles expressing only Syt-7 or Syt-1 were triggered to fuse on planar supported bilayers bearing plasma membrane SNARE proteins. Here, as in cells, Syt-7 confers substantially greater calcium sensitivity to vesicle fusion than Syt-1 and slows the rate at which cargos are released. Overall, this study demonstrates that by virtue of its high affinity for calcium, Syt-7 plays a central role in regulating secretory output from adrenal chromaffin cells.

Delay in vesicle fusion revealed by electrochemical monitoring of single secretory events in adrenal chromaffin cells

Nature ◽  
1992 ◽  
Vol 356 (6364) ◽  
pp. 60-63 ◽  
Author(s):  
Robert H. Chow ◽  
Ludolf von Rüden ◽  
Erwin Neher
Keyword(s):  
Chromaffin Cells ◽  
Vesicle Fusion ◽  
Adrenal Chromaffin Cells ◽  
Adrenal Chromaffin ◽  
Electrochemical Monitoring

Granule matrix property and rapid “kiss-and-run” exocytosis contribute to the different kinetics of catecholamine release from carotid glomus and adrenal chromaffin cells at matched quantal size

2012 ◽  
Vol 90 (6) ◽  
pp. 791-801 ◽  
Author(s):  
Nan Wang ◽  
Andy K. Lee ◽  
Lei Yan ◽  
Michael R. Simpson ◽  
Amy Tse ◽  
...  
Keyword(s):  
Chromaffin Cells ◽  
Dense Core ◽  
Fusion Pore ◽  
Adrenal Chromaffin Cells ◽  
Glomus Cells ◽  
Quantal Size ◽  
Dense Core Granules ◽  
Adrenal Chromaffin ◽  
Kinetics Of ◽  
Granule Matrix

Catecholamine-containing small dense core granules (SDCGs, vesicular diameter of ∼100 nm) are prominent in carotid glomus (chemosensory) cells and some neurons, but the release kinetics from individual SDCGs has not been studied in detail. In this study, we compared the amperometric signals from glomus cells with those from adrenal chromaffin cells, which also secrete catecholamine but via large dense core granules (LDCGs, vesicular diameter of ∼200–250 nm). When exocytosis was triggered by whole-cell dialysis (which raised the concentration of intracellular Ca2+ ([Ca2+]i) to ∼0.5 µmol/L), the proportion of the type of signal that represents a flickering fusion pore was 9-fold higher for glomus cells. Yet, at the same range of quantal size (Q, the total amount of catecholamine that can be released from a granule), the kinetics of every phase of the amperometric spike signals from glomus cells was faster. Our data indicate that the last phenomenon involved at least 2 mechanisms: (i) the granule matrix of glomus cells can supply a higher concentration of free catecholamine during exocytosis; (ii) a modest elevation of [Ca2+]i triggers a form of rapid “kiss-and-run” exocytosis, which is very prevalent among glomus SDCGs and leads to incomplete release of their catecholamine content (and underestimation of their Q value).

Morphological Observations on the Granule Types in Rabbit Extra-Adrenal Chromaffin Cells.

1975 ◽  
Vol 33 ◽  
pp. 318-319
Author(s):  
Joe A. Mascorro ◽  
Robert D. Yates
Keyword(s):  
Chromaffin Cells ◽  
Sodium Phosphate ◽  
Ganglion Cells ◽  
Ultrastructural Level ◽  
Osmic Acid ◽  
Adrenal Chromaffin Cells ◽  
Potassium Iodate ◽  
Perfusion Fluid ◽  
New Zealand White Rabbits ◽  
Adrenal Chromaffin

Extra-adrenal chromaffin organs (abdominal paraganglia) constitute rich sources of catecholamines. It is believed that these bodies contain norepinephrine exclusively. However, the present workers recently observed epinephrine type granules in para- ganglion cells. This report investigates catecholamine containing granules in rabbit paraganglia at the ultrastructural level.New Zealand white rabbits (150-170 grams) were anesthetized with 50 mg/kg Nembutal (IP) and perfused with 3% glutaraldehyde buffered with 0.2M sodium phosphate, pH 7.3. The retroperitoneal tissue blocks were removed and placed in perfusion fluid for 4 hours. The abdominal paraganglia were dissected from the blocks, diced, washed in phosphate buffer and fixed in 1% osmic acid buffered with phosphate. In other animals, the glutaraldehyde perfused tissue blocks were immersed for 1 hour in 3% glutaraldehyde/2.5% potassium iodate buffered as before. The paraganglia were then diced, separated into two vials and washed in the buffer. A portion of this tissue received osmic acid fixation.

scholarly journals Stimulatory effect of serotonin on Na+-dependent Ca2+ efflux from bovine adrenal chromaffin cells in culture

1997 ◽  
Vol 73 ◽  
pp. 226
Author(s):  
Kazuo Minakuchi ◽  
Hitoshi Houchi ◽  
Masanori Yoshizumi ◽  
Yasuko Ishimura ◽  
Kyoji Morita ◽  
...  
Keyword(s):  
Chromaffin Cells ◽  
Adrenal Chromaffin Cells ◽  
Cells In Culture ◽  
Adrenal Chromaffin
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