Usefulness of HeLa cells to evaluate inverse agonistic activity of antihistamines

Quantitative electrophysiological monitoring of anti–histamine drug effects on live cells via reusable sensor platforms

“…The result is also consistent with previous reports showing that chlorphenamine was a stronger inverse agonist than cetirizine (Christophe et al, 2003;Mizuguchi et al, 2013).…”

“…compared with the response of non−pretreated cells. It implies that ~60% of H1Rs on a cell membrane shifted to inactive forms by chlorphenamine, which was consistent with previous results measured by conventional methods (Mizuguchi et al, 2013).…”

“…HeLa cells are known to possess histamine receptors including H1Rs (Mizuguchi et al, 2013;Sauve et al, 1991). In a resting state, ion channels such as SOCCs and VDCCs on a cell membrane are closed.…”

“…In this work, we evaluated the effects of cetirizine and chlorphenamine as antihistamine drugs which were known as inverse agonists. Once inverse agonists bind with H1Rs, the H1Rs are converted to inactive forms, and the receptor activity of cells is down−regulated (Mizuguchi et al, 2013). Thus, the activation of H1Rs by histamine is degraded, resulting in the decrease of a Ca 2+ influx through SOCCs into the cells.…”

“…These conductance changes were attributed to a Ca 2+ influx through ion channels on a HeLa cell membrane due to the activation of H1Rs by histamine. The pretreatments of HeLa cells with anti−histamine drugs such as cetirizine or chlorphenamine reduced a Ca 2+ influx into the cells, which indicates that the activation of H1Rs was inhibited by anti−histamine drugs (Mizuguchi et al, 2013). Importantly, for each experimental set, we utilized only a single device to evaluate the activity of H1Rs in multiple HeLa cells, which allowed us to obtain statistically meaningful and quantitative results about the antihistamine drug effects without errors from device−to−device variations.…”