Catecholamine content and in vitro catecholamine synthesis in peripheral human lymphocytes

• Published in: The journal of clinical endocrinology and metabolism 1996-10, Vol.81 (10), p.3553-3557
• Main Authors: MUSSO, N. R, BRENCI, S, SETTI, M, INDIVERI, F, LOTTI, G, FRESA, R
• Format: Article
• Language: English
• Subjects: Adult; alpha-Methyltyrosine; Aromatic Amino Acid Decarboxylase Inhibitors; B-Lymphocytes - metabolism; Benserazide - pharmacology; Biological and medical sciences; Catecholamines - biosynthesis; Catecholamines - metabolism; Cell metabolism, cell oxidation; Cell physiology; Chromatography, High Pressure Liquid; Disulfiram - pharmacology; Dopamine - biosynthesis; Dopamine beta-Hydroxylase - antagonists & inhibitors; Enzyme Inhibitors - pharmacology; Female; Fundamental and applied biological sciences. Psychology; Fusaric Acid - pharmacology; Humans; Levodopa - biosynthesis; Levodopa - metabolism; Male; Methyltyrosines - pharmacology; Molecular and cellular biology; Norepinephrine - biosynthesis; T-Lymphocytes - metabolism; Tyrosine - metabolism; Tyrosine 3-Monooxygenase - antagonists & inhibitors
• ISSN: 0021-972X; 1945-7197
• DOI: 10.1210/jc.81.10.3553

We studied the catecholamine (CA) content in peripheral human lymphocytes and the ability of these cells to synthesize CA in vitro. CA were separated by high performance liquid chromatography (HPLC) and determined in the supernatant by electrochemical detection as well as being determined after ultrasonic cell disruption in mononuclear leukocytes, adherent cells (monocytes/macrophages), total lymphocytes, and B- and T-cell enriched fractions. T lymphocytes contained L-Dopa and norepinephrine (NE), whereas B lymphocytes contained only L-Dopa. Lymphocytes seem to be able to synthesize NE from both L-tyrosine and L-Dopa added to the incubation medium in concentrations similar to the peripheral venous plasma (i.e. 5 x 10(-5) m and 10(-8) m, respectively). The addition of D-Dopa did not increase intracellular NE. alpha-methyl-p-L-tyrosine, benserazide, disulfiram, and fusaric acid (which are inhibitors of the enzymatic pathway) all decreased the synthesis of NE. After the addition of [3H]-L-Dopa (10(-8) m and 10(-7) m) to the incubation medium, [3H]-NE and [3H]-dopamine appeared. By increasing the concentration of L-Dopa in the medium (< 10(-6) m), CA were detected in the supernatant as well. These data show that peripheral human T lymphocytes contain and are able to synthesize CA from normal precursors in physiologic concentrations, i.e. a CA synthetic pathway is shown in nonneural cells. These data seem to support the hypothesis of autocrine and paracrine loops in the regulation of lymphocyte activity in lymphocytes taken from human cerebrospinal fluid (as suggested by other authors).