Premium
Activation of serotonin receptors increase intracellular calcium in visceral neurons
Author(s) -
Davenport Jessica,
Kline David D
Publication year - 2007
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.21.5.a473
Subject(s) - agonist , serotonin , 5 ht receptor , calcium in biology , receptor , chemistry , calcium , endocrinology , medicine , intracellular , serotonin agonist , biology , biochemistry
Serotonin (5‐HT) is an important modulator of sensory cell activity and cardiorespiratory reflexes. 5‐HT modulates neuronal activity directly through ion channels or by downstream signaling to alter ion channel activity or intracellular stores. We examined the role of 5‐HT in mediating intracellular calcium concentrations in sensory neurons cultured from the nodose‐petrosal ganglia. Calcium concentrations were measured using Fura‐2 and the increase in the 340 to 380 nm ratio was used as an indicator of elevated intracellular calcium concentrations. 5‐HT (10 μM, 30s) increased 340/380 ratio in 10 of 18 cells. To determine the 5‐HT receptor mediating this increase, selective 5‐HT agonists were examined. The 5‐HT1 receptor agonists 5‐CT and 8‐OH‐DPAT (10 μM, n=2) did not alter the ratio alone. Co‐application of 8‐OH‐DPAT with 5‐HT, however, attenuated the increase in 340/380 ratio, agreeing with its described effects on increasing potassium current (Kline and Hendricks, 2005). The 5‐HT2 agonist α‐m‐5‐HT (10 μM, 30s) increased the 340/380 ratio (26.24%, n=3) as did the 5‐HT3 receptor agonist m‐CPBG (1 μM, 30s) which elicited a prolonged increase (40.38%, n=3). The increase in 340/380 by co‐application of all three agonists did not reach that of 5‐HT alone. These studies demonstrate several 5‐HT receptors modulate neuronal activity, in part, via increases in intracellular calcium. Support: AHA 0465225B .