Delayed effects of 1,2-epoxypropyltrimethylammonium chloride on behavioral reactions in rats.

We studied immediate and delayed effects of intraventricular injection of 1,2-epoxypropyltrimethylammonium chloride on behavioral reactions in rats. Apomorphine-induced yawning increased and orientation and exploratory activity was improved 144 h postinjection, which indicates activation of the brain dopaminergic system during this period.

Effects of 1,2,3,4-tetrahydroimidazo[4,5-c]-pyridine derivatives on ethanol oxidation by alcohol dehydrogenase isoforms from human liver.

We studied in vitro effects of four 1,2,3,4-tetrahydroimidazo[4,5-c]-pyridine derivatives formed in the reaction of the corresponding aldehydes with histidine on the rate of ethanol oxidation by alcohol dehydrogenase isoforms from human liver. None of test compounds inhibited ethanol oxidation by these enzymes. Some of them increased alcohol dehydrogenase activity to 220-240% of the initial level.

Chemical heterogeneity of [3H]imipramine binding sites on human platelet membranes.

Functional groups essential for high- and low-affinity [3H]imipramine (IMI) binding were determined by the method of chemical modification. The high-affinity recognition sites contained cysteine and lysine amino acid residues, but not aspartic or glutamic acid residues. The low-affinity recognition sites contained only cysteine residues.

High- and low-affinity [3H]imipramine binding sites on human platelets: separate determination and involvement of sulphur-containing bonds.

We have confirmed the presence of two different classes of [3H]imipramine ([3H]IMI) binding sites on human platelets: high-affinity (Kd = 0.52 nM, Bmax = 1670 fmol/mg protein) and low-affinity (Kd = 101 nM, Bmax = 8,000 fmol/mg protein) binding sites. The high-affinity component of [3H]IMI binding can also be obtained separately as the difference between specific [3H]IMI binding in Na-containing and Li-containing incubation buffer.