Na(+)-K(+)-ATPase-G protein coupling in myocardial sarcolemma: separation and reconstitution.

The cholinergic agonist carbachol produces a concentration-dependent (half-maximum inhibitory concentration = 0.9 microM) decrease in the Na(+)-K(+)-adenosine triphosphatase (ATPase) activity of rabbit cardiac sarcolemma that occurred only in the presence of guanosine 5'-[gamma-thio]triphosphate (0.1 microM GTP gamma S) and reached 40% inhibition.

Involvement of pertussis-toxin-sensitive G protein in muscarinic-receptor-mediated inhibition of K(+)-activated 4-nitrophenylphosphatase activity of cardiac sarcolemma.

The effects of the cholinergic agonist carbachol on ouabain-sensitive K(+)-activated 4-nitrophenylphosphatase (K(+)-O2NPhPase) activity of rabbit and pig ventricular sarcolemma were examined. Carbachol (0.01-1000 microM) alone had no effect on K(+)-O2NPase.

The effect of neomycin on contractile activity of the canine cervical lymphatic vessel induced by various agents.

The effects of neomycin on isometric contractions induced by norepinephrine (NE), alpha 1-adrenoceptor agonist phenylephrine (PE), KCl, and an activator of GTP-binding proteins (G-proteins) NaF were studied in the isolated canine cervical lymphatic vessel (CLV). Incubation of the CLV with 0.3 or 1.