scholarly journals Inositol 1,4,5-Trisphosphate- and Caffeine-Sensitive Ca2+-Storing Organelle in Bovine Adrenal Chromaffin Cells

1996 ◽  
Vol 72 (4) ◽  
pp. 307-315 ◽  
Author(s):  
Hiroki Teraoka ◽  
Ryo Takai ◽  
Tetsuro Taneike ◽  
Takeo Hiraga ◽  
Akira Ohga
Keyword(s):  
Chromaffin Cells ◽  
Adrenal Chromaffin Cells ◽  
Inositol 1,4,5 Trisphosphate ◽  
Adrenal Chromaffin

scholarly journals Thapsigargin-sensitive Ca2+-ATPases account for Ca2+ uptake to inositol 1,4,5-trisphosphate-sensitive and caffeine-sensitive Ca2+ stores in adrenal chromaffin cells

1995 ◽  
Vol 307 (3) ◽  
pp. 749-758 ◽  
Author(s):  
J C J Poulsen ◽  
C Caspersen ◽  
D Mathiasen ◽  
J M East ◽  
R E A Tunwell ◽  
...  
Keyword(s):  
Adrenal Medulla ◽  
Chromaffin Cells ◽  
Plasma Membranes ◽  
Ryanodine Receptors ◽  
Strongly Correlated ◽  
Adrenal Chromaffin Cells ◽  
Distribution Profile ◽  
Plasmic Reticulum ◽  
Inositol 1,4,5 Trisphosphate ◽  
Adrenal Chromaffin

In chromaffin cells of adrenal medulla, heterogeneity of Ca2+ stores has been suggested with respect to the mechanisms of Ca2+ uptake and release. We have examined Ca(2+)-ATPases responsible for loading of Ca2+ stores in these cells for their sensitivity to thapsigargin, a highly selective inhibitor of the SERCA [sarco(endo)plasmic reticulum calcium ATPase] family of intracellular Ca2+ pumps. Using immunostaining, we studied the distribution of Ca(2+)-ATPases, and of receptors for inositol 1,4,5-trisphosphate (InsP3) and ryanodine, in the density-gradient fractions of microsomes from bovine adrenal medulla. In parallel, we examined distribution profiles of ATP-dependent Ca2+ uptake in the same fractions, along with subcellular markers for plasma membranes and endoplasmic reticulum (ER). Two Ca(2+)-ATPase-like proteins (116 and 100 kDa) were detected, consistent with the presence of SERCA 2b and SERCA 3 isoenzymes of Ca2+ pumps. The distribution of these putative Ca(2+)-ATPase iso-enzymes paralleled that of InsP3 and ryanodine receptors. This distribution of ER Ca(2+)-ATPases, as determined immunologically, was consistent with that of thapsigargin-sensitive, but not of thapsigargin-insensitive, ATP-dependent Ca2+ uptake. In contrast, the distribution profile of the thapsigargin-insensitive Ca2+ uptake was strongly correlated to that of plasma membranes, and co-distributed with plasma membrane Ca(2+)-ATPase detected immunologically. In isolated, permeabilized chromaffin cells, InsP3 and caffeine induced Ca2+ release following an ATP-dependent Ca2+ accumulation to the stores. This accumulation was abolished by thapsigargin. Together, these data strongly indicate that the thapsigargin-sensitive, presumably SERCA-type Ca(2+)-ATPases account for Ca2+ uptake to InsP3-sensitive, as well as to caffeine-sensitive, Ca2+ stores in bovine adrenal chromaffin cells.

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.

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