Extracellular magnesium concentration alters Purkinje cell responsiveness to serotonin and analogues

• Published in: European journal of pharmacology Vol. 209; no. 1-2; p. 19
• Main Authors: Darrow, E, Strahlendorf, J C, Strahlendorf, H K
• Format: Journal Article
• Language: English
• Published: Netherlands 10-12-1991
• Subjects: 8-Hydroxy-2-(di-n-propylamino)tetralin; Animals; Extracellular Space - metabolism; Iontophoresis; Magnesium - pharmacology; Male; Piperazines - pharmacology; Purkinje Cells - drug effects; Purkinje Cells - physiology; Rats; Rats, Inbred Strains; Receptors, Serotonin - drug effects; Receptors, Serotonin - physiology; Serotonin - pharmacology; Serotonin - physiology; Tetrahydronaphthalenes - pharmacology
• ISSN: 0014-2999
• DOI: 10.1016/0014-2999(91)90005-B

Binding studies have shown that divalent cations increase the affinity of 5-hydroxytryptamine 1A (5-HT1A) receptors for ligands. The present study compared the effects of magnesium (Mg2+) at physiologic (1.15 mM) and low (0.56 mM) concentrations on firing rate responses of cerebellar Purkinje cells induced by 5-HT and selective 5-HT1 agonists applied by superfusion or iontophoresis. In low Mg2+ concentrations, the inhibitory actions of 5-HT and 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) but not meta-trifluoromethyl phenyl piperazine (TFMPP) on Purkinje cells were significantly reduced; whereas the excitatory actions to the physiologic agonist 5-HT were enhanced. This report demonstrates a functional role for Mg2+ in the operation of the 5-HT1A receptor located on Purkinje cells.