scholarly journals Augmentation and inhibition of .BETA.-adrenergic agonists-stimulated tissue cyclic AMP accumulation by .ALPHA.-adrenergic agonists in rat parotid gland.

1987 ◽  
Vol 37 (5) ◽  
pp. 881-897 ◽  
Author(s):  
Keiichi YOSHIMURA ◽  
Eriko NEZU ◽  
Toshie YONEYAMA ◽  
Yukiharu HIRAMATSU
1973 ◽  
Vol 51 (12) ◽  
pp. 997-1001 ◽  
Author(s):  
B. Harfield ◽  
A. Tenenhouse

An attempt was made to determine whether accumulation of cyclic AMP (cAMP) was essential for epinepnrine-stimuiated secretion of protein from the rat parotid gland in vitro. EGTA (10−2 M) did not inhibit secretion but did reduce cAMP accumulation by 80% suggesting that this nucleotide may not be an essential intermediate in the epinephrine-stimuiated secretion process.


2005 ◽  
Vol 182 (1) ◽  
pp. 104-115 ◽  
Author(s):  
Han-Ting Zhang ◽  
Ying Huang ◽  
Kathleen Mishler ◽  
Sandra C. Roerig ◽  
James M. O'Donnell

1978 ◽  
Vol 176 (1) ◽  
pp. 53-66 ◽  
Author(s):  
A K Campbell ◽  
R L Dormer

1. Sealed pigeon erythrocyte ‘ghosts’ were prepared containing ATP and the Ca2+-activated photoprotein obelin to investigate the relationship cyclic AMP formation and internal free Ca2+. 2. The ‘ghosts’ were characterized by (a) morphology (optical and electron microscopy), (b) composition (haemoglobin, K+, Na+, Mg2+, ATP, obelin), (c) permeability to Ca2+, assessed by obelin luminescence and (d) hormone sensitivity (the effect of beta-adrenergic agonists and antagonists on cyclic AMP formation). 3. The effect of osmolarity at haemolysis and ATP at resealing on these parameters was investigated. 4. Sealed ‘ghosts’, containing approx. 2% of original haemoglobin, 150mM-K+, 0.5MM-ATP, 10(3)–10(4) obelin luminescence counts/10(6) ‘ghosts’, which were relatively impermeable to Ca2+ and in which cyclic AMP formation was stimulated by beta-adrenergic agonists over a concentration range similar to that for intact cells, could be prepared after haemolysis in 6mM-NaCl3mM-MgCl2/50mM-Tes, pH7, and resealing for 30min at 37 degrees C in the presence of ATP and 150mM-KCl. 5. The initial rate of adrenaline-stimulated cyclic AMP formation in these ‘ghosts’ was 30–50% of that in intact cells and was inhibited by the addition of extracellular Ca2+. Addition of Ca2+ to the ‘ghosts’ resulted in a stimulation of obelin luminescence, indicating an increase in internal free Ca2+ under these conditions. 6. The ionophore A23187 increased the rate of obelin luminescence in the ‘ghosts’ and also inhibited the adrenaline-stimulated increase in cyclic AMP. 7. The effect of ionophore A23187 on obelin luminescence and on cyclic AMP formation in the ‘ghosts’ was markedly decreased by sealing EGTA inside the ‘ghosts’. 8. It was concluded that cyclic AMP formation inside sealed pigeon erythrocyte ‘ghosts’ could be inhibited by more than 50% by free Ca2+ concentrations in the range 1–10 micrometer.


1979 ◽  
Vol 88 (6) ◽  
pp. 1467-1469
Author(s):  
K. N. Yarygin ◽  
N. V. Nechaeva ◽  
V. I. Fateeva ◽  
T. E. Novikova ◽  
V. Ya. Brodskii

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