Effect of local anesthetic [2-(alkyloxy)phenyl]-2-(1-piperidinyl)ethyl esters of carbamic acid on the activity of purified sarcoplasmic reticulum (Ca-Mg)ATPase.

Local anesthetic [2-(alkyloxy)phenyl]-2-(1-piperidinyl)ethyl esters of carbamic acid modulate the activity of the purified sarcoplasmic reticulum (Ca-Mg)ATPase. The phase of insensitivity or slight stimulation of the activity at lower anesthetics concentrations is followed by the inhibition phase at higher concentrations. The potency to inhibit the activity at high concentrations is maximal for the homologue with the hexyloxy substituent and decreases for shorter and longer substituents. The inhibition of activity can be partially reversed by addition of n-decane. The inhibition could be caused by the binding of anesthetics to binding sites at the protein--lipid bilayer interface. The changed thickness of the hydrophobic part of this interface might be responsible for the n-decane reversible inhibition and its dependence on the alkyloxy substituent chain length, while the changed structure of the polar part of this interface could be the cause of the n-decane irreversible inhibiton.