Acidic phospholipids and lysophospholipids stimulate cAMP phosphodiesterase of rat liver microsomal membranes.
Acidic phospholipids and lysophospholipids modify cAMP phosphodiesterase activity of rat liver microsomal membranes to different extents, depending on the cAMP concentrations employed. At low concentrations, they activate the hormone-sensitive low-Km form of the enzyme through an increase of Vmax (diphosphatidylglycerol greater than phosphatidylglycerol greater than phosphatidic acid = lysophosphatidylserine greater than phosphatidylserine greater than lysophosphatidylcholine). At high concentrations, only lysophospholipids activate the high-Km form of phosphodiesterase through a marked increase in both Vmax and apparent Km for the cAMP.
Carpenedo
F
F
Department of Pharmacology, University of Padova, Italy.
Floreani
M
M
D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000378:metabolism*; D000818:Animals; D003902:Detergents; D006863:Hydrogen-Ion Concentration; D007425:Intracellular Membranes / Q000201:enzymology*; D007700:Kinetics; D008246:Lysophospholipids / Q000378:metabolism*; D008862:Microsomes, Liver / Q000201:enzymology* / Q000648:ultrastructure; D010743:Phospholipids / Q000378:metabolism*; D051381:Rats
D003902:Detergents; D008246:Lysophospholipids; D010743:Phospholipids; D015105:3',5'-Cyclic-AMP Phosphodiesterases