High-performance liquid chromatography of tetrahydro-β-carbolines extracted from plasma and platelets

Occurence and partition of the β-carboline norharman in rat organs

“…Chromatography and extraction. The use of fully endcapped Zorbax C8 material made the addltion of the ion-pair former sodium octylsulfate in the HPLC solvents unnecessary (7). With this HPLC procedure it was also possible to determine all 5 B-carbolines together with their 3 precursor amines in a slngle run ( Figure IA).…”

High-performance liquid chromatographic analysis of β-carbolines in human scalp hair

“…Since the condensation between indoleamines and aldehydes readily proceeds even under laboratorial conditions, ␤-carbolines are artifactually produced during sample work-up and the resulting artifacts are analyzed concomitantly with the original ones [21,22]. Beta-carbolines are contained in biological samples together with structurally related compounds and at low concentrations (pg/ml to ng/ml levels), requiring a very specific and sensitive method for their quantitation [20,23,24]. Hair samples have been routinely digested by heating in 0.1-1.0 M HCl or NaOH at 56-80 • C for 0.5-12 h [14,15,25].…”

“…When standard tryptamine solutions (50 ng/ml) were incubated under enzymatic reaction conditions for 30 min and extracted by the solid-phase and liquid-phase methods widely used for purifying biological samples, ␤-carbolines of pg levels were produced from contaminant aldehydes [23]. In order to inhibit the artifactual production of ␤-carbolines during hair digestion, sample solutions were treated with semicarbazide that trapped the precursor aldehydes contaminated in samples [24,26]. The hair digests were subsequently reacted with fluorescamine to convert precursor amines to carboxylic derivatives which were removed from the analytical system by solvent extractions, resulting in not only effective inhibition of the artifactual formation but also selective purification of ␤-carbolines as reported previously [3,20,23].…”

Binding of Pinoline on the 5‐Hydroxytryptamine Transporter: Competitive Interaction with [3H] Citalopram

“…This compound has been found in pineal and adrenal glands, in retina and in brain in concentrations ranging from 2 ng/g or below that (Barker et al 1981;Langer et al 1986), 0.1-1 pg/g (Leino et al 1983;Kari et al 1983) up to concentration 21 pg/g (Langer et al 1984b). In rat and human blood the concentration of endogenous pinoline has been found below the detection limit, although pinoline has been found in trace amounts in human platelets (Schouten & Bruinvels 1985).…”