The Pharmacological Effects of Herbs on Catecholamine Signaling

Herbs have many biologically and pharmacologically active compounds such as flavonoids and stilbenes. They have been used in remedies for various disorders. Here we review the effects of herbs on catecholamine synthesis and secretion in cultured bovine adrenal medullary cells. Ikarisoside A (1.0–100 μ M), a flavonol glycoside, inhibited the catecholamine secretion induced by acetylcholine (0.3 mM). This inhibition was associated with the suppression of 22 Na + and 45 Ca 2+ influx induced by acetylcholine. The ethanol extract (0.0003–0.005%) of matsufushi (extract of pine nodules) inhibited the catecholamine secretion induced by acetylcholine. SJ-2, one of the stilbene compounds isolated from matsufushi, inhibited acetyl-choline-induced catecholamine secretion. Matsufushi extract and SJ-2 reversibly inhibited acetylcholine-induced Na + currents in Xenopus oocytes expressed with α 3 β 4nicotinic acetylcholine receptors. Sweet tea is the processed leaves of Hydrangea macrophylla . The extract of sweet tea (0.3–1.0 mg/ml) suppressed catecholamine secretion induced by acetylcholine (0.3 mM). Moreover, sweet tea (0.1–1.0 mg/ml), ikarisoside A (1.0–100 μ M), and matsufushi (0.001–0.003%) or SJ-2 (10–30 μ M) inhibited acetylcholine-induced 14 C-catecholamine synthesis from 14 C-tyrosine. These findings indicate that ikarisoside A, matsufushi (or SJ-2), and sweet tea inhibit the catecholamine secretion and synthesis induced by acetylcholine in cultured bovine adrenal medullary cells and probably in sympathetic neurons.