Polyvanadate acts at the level of plasma membranes through α-adrenergic receptor and affects cellular calcium distribution and some oxidation activities

1990 ◽  
Vol 15 (3) ◽  
pp. 205-210 ◽  
Author(s):  
T. Ramasarma ◽  
Sharada Gullapalli ◽  
Vidya Shivaswamy ◽  
C. K. Ramakrishna Kurup
Keyword(s):  
Adrenergic Receptor ◽  
Plasma Membranes ◽  
Cellular Calcium ◽  
Calcium Distribution

Cellular calcium distribution in fetal bones studied with K-pyroantimonate

1978 ◽  
Vol 26 (1) ◽  
pp. 181-190 ◽  
Author(s):  
E. H. Burger ◽  
J. L. Matthews
Keyword(s):  
Cellular Calcium ◽  
Calcium Distribution

scholarly journals Stimulation of calcium-ATPase activity by 3,5,3′-tri-iodothyronine in rat thymocyte plasma membranes. A possible role in the modulation of cellular calcium concentration

1989 ◽  
Vol 261 (3) ◽  
pp. 749-754 ◽  
Author(s):  
J Segal ◽  
J Hardiman ◽  
S H Ingbar
Keyword(s):  
Atpase Activity ◽  
Calcium Metabolism ◽  
Plasma Membranes ◽  
Calcium Concentration ◽  
Free Calcium ◽  
Physiological Concentration ◽  
Calmodulin Antagonist ◽  
Adrenergic Agents ◽  
Cellular Calcium ◽  
Free Calcium Concentration

We have previously demonstrated that 3,5,3′-tri-iodo-L-thyronine (T3) produces a very rapid and transient increase in calcium uptake and cytoplasmic free calcium concentration in the rat thymocyte, and have postulated that Ca2+-ATPase may contribute to the overall effect of T3 on cellular calcium metabolism. In the present study, we show that in the rat thymocyte, T3 increased plasma membrane Ca2+-ATPase activity. This effect of T3 was very rapid, seen at 30 s after the addition of the hormone, and was concentration-related, evident at a physiological concentration as low as 1 pM. Evaluation of the effect of several thyronine analogues on Ca2+-ATPase activity revealed the following order of potency: D-T3 greater than or equal to 3′-isopropyl-L-T2 = L-T3 = L-T4 = D-T4 greater than L-rT3 greater than 3,5-L-T2 greater than DL-thyronine. Studies with the calmodulin antagonist trifluoperazine demonstrated that thymocyte Ca2+-ATPase activity and its stimulation by T3 are influenced by calmodulin. Other studies showed that several adrenergic agents, agonists and antagonists, had no effect on thymocyte Ca2+-ATPase activity and its stimulation by T3. From these and previous observations, we would suggest that in the rat thymocyte, the T3-induced increase in Ca2+-ATPase activity, which enhances the expulsion of calcium from the cell, plays a role in the diminution and transiency of the stimulatory effect of T3 on thymocyte calcium metabolism.

Ligand specificity and characteristics of the β-adrenergic receptor in turkey erythrocyte plasma membranes

1975 ◽  
Vol 97 (1) ◽  
pp. 35-53 ◽  
Author(s):  
Alexander Levitzki ◽  
Nehama Sevilia ◽  
Daphne Atlas ◽  
Michael L. Steer
Keyword(s):  
Adrenergic Receptor ◽  
Plasma Membranes ◽  
Ligand Specificity

Role of pectin methylesterases in cellular calcium distribution and blossom-end rot development in tomato fruit

2012 ◽  
Vol 71 (5) ◽  
pp. 824-835 ◽  
Author(s):  
Sergio T. de Freitas ◽  
Avtar K. Handa ◽  
Qingyu Wu ◽  
Sunghun Park ◽  
Elizabeth J. Mitcham
Keyword(s):  
Tomato Fruit ◽  
Cellular Calcium ◽  
Calcium Distribution ◽  
Blossom End Rot

Cellular calcium transport in renal epithelia: measurement, mechanisms, and regulation

1995 ◽  
Vol 75 (3) ◽  
pp. 429-471 ◽  
Author(s):  
P. A. Friedman ◽  
F. A. Gesek
Keyword(s):  
Plasma Membranes ◽  
Single Channel ◽  
Calcium Absorption ◽  
Vital Role ◽  
Channel Blockers ◽  
Calcium Efflux ◽  
Cellular Calcium ◽  
Wide Range ◽  
Active Calcium ◽  
Convoluted Tubules

The kidneys play a vital role in mineral homeostasis. In this review, the handling of calcium and the methods currently applied to measuring its intracellular concentration are discussed. The bulk of calcium absorption proceeds in proximal tubules, with smaller fractions recovered by thick ascending limbs, distal convoluted tubules, and connecting tubules. Hormonally regulated transcellular calcium absorption is essentially limited to distal convoluted and connecting tubules. At physiological concentrations, parathyroid hormone, calcitonin, and vitamin D increase net calcium absorption. Calcium absorption by polarized epithelial cells is a two-step process wherein calcium enters the cell across apical plasma membranes and exits across basolateral membranes. Recent electrophysiological and pharmacological experiments demonstrate that apical entry is mediated by calcium channels, which are modestly calcium selective, sensitive to dihydropyridine-type calcium channel blockers, and exhibit a wide range of single-channel conductances. Cellular calcium efflux is mediated by Ca(2+)-ATPase and by Na+/Ca2+ exchange. Ca(2+)-ATPase activity is highest in segments that exhibit significant rates of active calcium absorption. Multiple plasma membrane Ca(2+)-ATPase isoforms have been found in the kidney. Several renal Na+/Ca2+ exchange isoforms have been identified, and their role in effecting calcium efflux is under investigation.

β-adrenergic receptor binding in crude porcine adipose tissue plasma membranes

1992 ◽  
Vol 70 (3) ◽  
pp. 781-786 ◽  
Author(s):  
H. J. Mersmann ◽  
R. L. McNeel
Keyword(s):  
Adipose Tissue ◽  
Receptor Binding ◽  
Adrenergic Receptor ◽  
Plasma Membranes

scholarly journals Regulation of hepatocyte plasma membrane α1-adrenergic receptors by 4β-phorbol 12-myristate 13-acetate

1995 ◽  
Vol 305 (1) ◽  
pp. 73-79 ◽  
Author(s):  
J F Beeler ◽  
R H Cooper
Keyword(s):  
Plasma Membrane ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Cell Surface ◽  
Adrenergic Receptors ◽  
Adrenergic Receptor ◽  
Plasma Membranes ◽  
Complete Recovery ◽  
Maximal Inhibition ◽  
Kinase C

The effect of phorbol 12-myristate 13-acetate (PMA) on hepatocyte alpha 1-adrenergic receptors was determined by [3H]prazosin binding to plasma membranes from control and PMA-treated hepatocytes. Membranes from hepatocytes incubated with PMA (1 microgram/ml) for 1 h exhibited a 40% decrease in alpha 1-adrenergic receptors (481 +/- 10 fmol/mg of protein; mean +/- S.E.M. for three separate experiments) relative to vehicle-treated (dimethylformamide) hepatocytes (802 +/- 91 fmol/mg of protein; n = 3), with no significant effect on the KD. The PMA-induced decrease in alpha 1-adrenergic receptors was maximal by 30 min and half-maximal inhibition of [3H]prazosin binding occurred with a PMA concentration of approx. 15 ng/ml. Pretreatment of hepatocytes with staurosporine (5 microM) blocked the effect of PMA, and 4 beta-phorbol 13-monoacetate was ineffective, suggesting the involvement of protein kinase C (PKC). Treatment of hepatocytes with primaquine (300 microM) for 15 min decreased hepatocyte plasma membrane alpha 1-adrenergic receptors by 34.0 +/- 2.4% (mean +/- S.E.M. of three experiments). Removal of primaquine allowed essentially complete recovery (98 +/- 4%; mean +/- S.E.M. for five separate experiments) of plasma membrane [3H]prazosin binding within 20 min, suggesting that the alpha 1-adrenergic receptor undergoes endocytotic recycling. Addition of PMA (1 microgram/ml) to hepatocytes immediately after removal of primaquine, completely inhibited the increase in plasma membrane alpha 1-adrenergic receptors relative to control cells, but had no effect on hepatocytes whose cell surface alpha 1-receptors remaining after primaquine treatment had been inactivated by alkylation. These observations suggested that activation of PKC may facilitate the internalization of the alpha 1-adrenergic receptor in hepatocytes.

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