Direct inhibition of smooth muscle myosin light chain kinase by arachidonic acid in a purified system.
The direct effect of arachidonic acid (AA) on the phosphorylation of smooth muscle myosin light chain (SMLC) by smooth muscle myosin light chain kinase (SMLCK) was assessed in a purified system. AA inhibited the phosphorylation of SMLC by SMLCK in a dose dependent manner. Increasing the amount of calmodulin (59 nM and 590 nM) did not reverse this inhibition. Linoleic acid and oleic acid also inhibited the phosphorylation. The inhibitory potency of these unsaturated fatty acids paralleled the number of cis double bonds. These results show that SMLCK is directly inhibited by unsaturated fatty acids including AA.
Kigoshi
T
T
Department of Internal Medicine, Kanazawa Medical University, Ishikawa, Japan.
Uchida
K
K
Kaneko
M
M
Iwasaki
R
R
Nakano
S
S
Azukizawa
S
S
Morimoto
S
S
D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000494:pharmacology*; D002147:Calmodulin / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology; D066298:In Vitro Techniques; D009130:Muscle, Smooth; D009219:Myosin-Light-Chain Kinase / Q000037:antagonists & inhibitors*; D009218:Myosins / Q000378:metabolism*; D010743:Phospholipids / Q000494:pharmacology; D014422:Turkeys
D001095:Arachidonic Acids; D002147:Calmodulin; D005231:Fatty Acids, Unsaturated; D010743:Phospholipids; D016718:Arachidonic Acid; D009219:Myosin-Light-Chain Kinase; D009218:Myosins