Effects of protein kinase inhibitors and protein phosphatase inhibitors on cyclic AMP-dependent down-regulation of vesicular monoamine transport in pheochromocytoma PC12 cells.
Cyclic AMP down-regulates vesicular monoamine transport in PC12 cells and thereby decreased catecholamine reuptake from the extracellular fluid. We examined the effects of protein kinase inhibitors and protein phosphatase inhibitors on this cAMP action. Treatment of cells with a protein kinase inhibitor, K252a, increased vesicular amine transport and cellular amine uptake, thereby antagonizing the regulatory action of cAMP. In contrast, a protein phosphatase inhibitor, okadaic acid, had the opposite effect on the amine transport, i.e. it enhanced the cAMP action. These results suggest the involvement of a protein phosphorylation process in the cAMP-dependent modulation of vesicular monoamine transport.
Nakanishi
N
N
Department of Biochemistry, Meikai University School of Dentistry, Saitama, Japan.
Onozawa
S
S
Matsumoto
R
R
Kurihara
K
K
Ueha
T
T
Hasegawa
H
H
Minami
N
N
D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism*; D001692:Biological Transport; D003994:Bucladesine / Q000494:pharmacology; D002227:Carbazoles / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism*; D015536:Down-Regulation; D004988:Ethers, Cyclic / Q000494:pharmacology; D006023:Glycoproteins / Q000378:metabolism*; D026121:Indole Alkaloids; D008387:Marine Toxins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009479:Neuropeptides; D009638:Norepinephrine / Q000494:pharmacology; D019319:Okadaic Acid; D010080:Oxazoles / Q000494:pharmacology; D016716:PC12 Cells; D010673:Pheochromocytoma / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors*; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors; D051381:Rats; D012701:Serotonin / Q000378:metabolism; D050492:Vesicular Biogenic Amine Transport Proteins
D015306:Biogenic Monoamines; D002227:Carbazoles; D004988:Ethers, Cyclic; D006023:Glycoproteins; D026121:Indole Alkaloids; D008387:Marine Toxins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009479:Neuropeptides; D010080:Oxazoles; D047428:Protein Kinase Inhibitors; D050492:Vesicular Biogenic Amine Transport Proteins; D019319:Okadaic Acid; D012701:Serotonin; D003994:Bucladesine; C059041:calyculin A; C049985:staurosporine aglycone; D000242:Cyclic AMP; D010749:Phosphoprotein Phosphatases; D009638:Norepinephrine