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F R Ciofalo

Publications and source records attributed to F R Ciofalo.

17 recordsLinked to original sources
PubMed1981

Effects of some membrane perturbers on alpha 1-adrenergic receptor binding.

The ability of membrane perturbing drugs to inhibit the specific binding of [3H]/B4101 (2,6-dimethoxyphenoxyethyl)aminomethyl-1,4-benzodioxane) to the alpha 1-receptor of beef cortical membranes was determined. Except for quinidine and phenytoin, the IC50 for inhibition of specific [3H]WB4101 binding to the alpha 1-receptor correlated with the membrane/buffer partition coefficient of the drug. Almost all of the drugs inhibited specific ligand binding at concentrations approaching those reported necessary to stabilize membranes although both activities correlate well with reported membrane/buffer partition coefficients. The results suggest that specific receptor function can be modified by drug perturbation of the lipid microenvironment of the receptor macromolecule.

Animals↗
PubMed1980

Effect of some antiarrhythmics on [3H]clonidine binding to alpha 2-adrenergic receptors.

The effects of the antiarrhythmics quinidine, propranolol, procainamide and lidocaine were determined on the specific binding of [3H]clonidine to the alpha 2-adrenergic receptor. Quinidine is effective in decreasing specific [3H]clonidine binding to the alpha 2 receptor within the range of therapeutic blood levels (Ki = 6 x 10 (-8) M). The effectiveness of all compounds tested, with the exception of quinidine and procainamide, correlate with the membrane/buffer partition coefficient, suggesting a relationship with the local anesthetic activity.

Animals↗
PubMed1979

Methadone binding at nonopiate receptor binding sites.

The binding of 3H-methadone to rabbit brain synaptosomes was studied. Binding was saturable at methadone concentrations below 10(-6)M and unsaturable above 10(-6)M. Except at high 3H-methadone concentrations, only a small fraction of the specific saturable binding of methadone was blocked by levorphanol, naloxone or morphine, suggesting that much of the saturable binding of methadone to rabbit synaptosomes is not binding at the opiate receptor. At low methadone concentrations, stereospecific methadone binding to the opiate receptor is essentially undetectable as determined by displacement with levorphanol and dextrorphan. Experiments with preparations from beef caudate, on the other hand, indicate that a larger percentage of the methadone bound to this preparation is bound to the opiate receptor but that some specific binding is also at other sites.

Animals↗