α2-Adrenoceptors in opossum kidney cells couple to stimulation of mitogen-activated protein kinase independently of adenylyl cyclase inhibition

1997 ◽  
Vol 356 (2) ◽  
pp. 225-232 ◽  
Author(s):  
Andreas Kribben ◽  
Stefan Herget-Rosenthal ◽  
Bettina Lange ◽  
Wilhelm Erdbrügger ◽  
Thomas Philipp ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Adenylyl Cyclase ◽  
Mitogen Activated Protein Kinase ◽  
Kidney Cells ◽  
Α2 Adrenoceptors ◽  
Opossum Kidney ◽  
Opossum Kidney Cells ◽  
Mitogen Activated Protein ◽  
Stimulation Of

scholarly journals Ouabain-insensitive acidification by dopamine in renal OK cells: primary control of the Na+/H+exchanger

2001 ◽  
Vol 281 (1) ◽  
pp. R10-R18 ◽  
Author(s):  
Pedro Gomes ◽  
M. A. Vieira-Coelho ◽  
P. Soares-da-Silva
Keyword(s):  
Adenylyl Cyclase ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Kidney Cells ◽  
Primary Control ◽  
Intracellular Acidification ◽  
Opossum Kidney ◽  
Opossum Kidney Cells ◽  
Stimulation Of

The present study was aimed at evaluating the role of D1- and D2-like receptors and investigating whether inhibition of Na+ transepithelial flux by dopamine is primarily dependent on inhibition of the apical Na+/H+ exchanger, inhibition of the basolateral Na+-K+-ATPase, or both. The data presented here show that opossum kidney cells are endowed with D1- and D2-like receptors, the activation of the former, but not the latter, accompanied by stimulation of adenylyl cyclase (EC50 = 220 ± 2 nM), marked intracellular acidification (IC50 = 58 ± 2 nM), and attenuation of amphotericin B-induced decreases in short-circuit current (28.6 ± 4.5% reduction) without affecting intracellular pH recovery after CO2 removal. These results agree with the view that dopamine, through the activation of D1- but not D2-like receptors, inhibits both the Na+/H+ exchanger (0.001933 ± 0.000121 vs. 0.000887 ± 0.000073 pH unit/s) and Na+-K+-ATPase without interfering with the Na+-independent HCO[Formula: see text] transporter. It is concluded that dopamine, through the action of D1-like receptors, inhibits both the Na+/H+ exchanger and Na+-K+-ATPase, but its marked acidifying effects result from inhibition of the Na+/H+exchanger only, without interfering with the Na+-independent HCO[Formula: see text] transporter and Na+-K+-ATPase.

D2-like receptor-mediated inhibition of Na+-K+-ATPase activity is dependent on the opening of K+ channels

2002 ◽  
Vol 283 (1) ◽  
pp. F114-F123 ◽  
Author(s):  
Pedro Gomes ◽  
P. Soares-da-Silva
Keyword(s):  
Protein Kinase ◽  
Atpase Activity ◽  
Receptor Activation ◽  
Inhibitory Effect ◽  
Skf 38393 ◽  
Kidney Cells ◽  
Dependent Manner ◽  
Opossum Kidney ◽  
Opossum Kidney Cells ◽  
Stimulation Of

This study examined the effects of D2-like dopamine receptor activation on Na+-K+-ATPase activity while apical-to-basal, ouabain-sensitive, amphotericin B-induced increases in short-circuit current and basolateral K+ ( I K) currents in opossum kidney cells were measured. The inhibitory effect of dopamine on Na+-K+-ATPase activity was completely abolished by either D1- or D2-like receptor antagonists and mimicked by D1- and D2-like receptor agonists SKF-38393 and quinerolane, respectively. Blockade of basolateral K+ channels with BaCl2 (1 mM) or glibenclamide (10 μM), but not apamin (1 μM), totally prevented the inhibitory effects of quinerolane. The K+ channel opener pinacidil decreased Na+-K+-ATPase activity. The inhibitory effect of quinerolane on Na+-K+- ATPase activity was abolished by pretreatment of opossum kidney cells with pertussis toxin (PTX). Quinerolane increased I K across the basolateral membrane in a concentration-dependent manner; this effect was abolished by pretreatment with PTX, S-sulpiride, and glibenclamide. SKF-38393 did not change I K. Both H-89 (protein kinase A inhibitor) and chelerythrine (protein kinase C inhibitor) failed to prevent the stimulatory effect of quinerolane on I K. The stimulation of the D2-like receptor was associated with a rapid hyperpolarizing effect, whereas D1-like receptor activation was accompanied by increases in cell membrane potential. It is concluded that stimulation of D2-like receptors leads to inhibition of Na+-K+-ATPase activity and hyperpolarization; both effects are associated with the opening of K+channels.

scholarly journals Ser/ Thr residues at α3/β5 loop of Gαs are important in morphine-induced adenylyl cyclase sensitization but not mitogen-activated protein kinase phosphorylation

FEBS Journal ◽  
2012 ◽  
Vol 279 (4) ◽  
pp. 650-660 ◽  
Author(s):  
Mohammad Seyedabadi ◽  
Seyed Nasser Ostad ◽  
Paul R. Albert ◽  
Ahmad R. Dehpour ◽  
Reza Rahimian ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Adenylyl Cyclase ◽  
Mitogen Activated Protein Kinase ◽  
Mitogen Activated Protein ◽  
Kinase Phosphorylation

Role of the PI3K/PKB signaling pathway in cAMP-mediated translocation of rat liver Ntcp

1999 ◽  
Vol 277 (6) ◽  
pp. G1165-G1172 ◽  
Author(s):  
Cynthia R. L. Webster ◽  
M. Sawkat Anwer
Keyword(s):  
Plasma Membrane ◽  
Protein Kinase ◽  
Signaling Pathway ◽  
Mitogen Activated Protein Kinase ◽  
Phosphatidylinositol 3 Kinase ◽  
Pi3k Inhibitors ◽  
Mapk Activity ◽  
Mitogen Activated Protein ◽  
Pi3k Signaling Pathway ◽  
Stimulation Of

cAMP stimulates Na+-taurocholate (TC) cotransport by translocating the Na+-TC-cotransporting peptide (Ntcp) to the plasma membrane. The present study was undertaken to determine whether the phosphatidylinositol-3-kinase (PI3K)-signaling pathway is involved in cAMP-mediated translocation of Ntcp. The ability of cAMP to stimulate TC uptake declined significantly when hepatocytes were pretreated with PI3K inhibitors wortmannin or LY-294002. Wortmannin inhibited cAMP-mediated translocation of Ntcp to the plasma membrane. cAMP stimulated protein kinase B (PKB) activity by twofold within 5 min, an effect inhibited by wortmannin. Neither basal mitogen-activated protein kinase (MAPK) activity nor cAMP-mediated inhibition of MAPK activity was affected by wortmannin. cAMP also stimulated p70S6K activity. However, rapamycin, an inhibitor of p70S6K, failed to inhibit cAMP-mediated stimulation of TC uptake, indicating that the effect of cAMP is not mediated via p70S6K. Cytochalasin D, an inhibitor of actin filament formation, inhibited the ability of cAMP to stimulate TC uptake and Ntcp translocation. Together, these results suggest that the stimulation of TC uptake and Ntcp translocation by cAMP may be mediated via the PI3K/PKB signaling pathway and requires intact actin filaments.

Sign in / Sign up

Export Citation Format

Share Document