Effects of free fatty acids on the muscle cell membrane and their possible relations to the depression of contraction.
High concentrations of free fatty acids (FFA) depolarize the resting muscle cell membrane and decrease the membrane resistance. In contrast, low concentrations have a "membrane stabilizing effect" which decreases action potential (AP) and voltage-dependent ionic currents. The changes of AP may result in a decrease of excitation-induced Ca++ release from cellular stores. This may be a causal factor for depression of contraction by FFA.
G
G
Caffier
F
F
Kössler
G
G
Küchler
D000818:Animals; D002208:Caproates / Q000494:pharmacology; D002210:Caprylates / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004553:Electric Conductivity; D005230:Fatty Acids, Nonesterified / Q000494:pharmacology*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects; D008563:Membrane Lipids / Q000502:physiology; D008564:Membrane Potentials / Q000187:drug effects; D009119:Muscle Contraction / Q000187:drug effects*; D009200:Myocardial Contraction / Q000187:drug effects*; D012508:Sarcolemma / Q000187:drug effects*
D002208:Caproates; D002210:Caprylates; D005230:Fatty Acids, Nonesterified; D007473:Ion Channels; D008563:Membrane Lipids; C037652:hexanoic acid; C031492:octanoic acid