H1-receptor displacement in control and histamine-pretreated U373 MG cells
Cell-based study · Intact human U373 MG astrocytoma cells [1]
Bepotastine displaced the H1 radioligand. Histamine pretreatment shifted its monophasic displacement curve to lower apparent potency. This is an intact-cell endpoint, not a receptor Ki or direct measurement of blood–brain barrier permeability.
| Endpoint | Reported result | Reference |
|---|---|---|
| Displacement of 5 nM [3H]mepyramine from intact-cell H1 receptors | pIC50 (−log[IC50 (M)]) Control: 5.70 ± 0.06; histamine-pretreated: 5.24 ± 0.07; mean ± S.E.M.; n = 3 independent experiments, quadruplicate determinations; P < 0.05 versus control. | [1] |
Literature-Reported Treatment Conditions
- Exposure duration
- Binding: 120 min at 4°C; histamine pretreatment: 30 min at 37°C.
- Method
- Concentration-dependent radioligand displacement, with or without prior 0.1 mM histamine; cells washed before binding.
- Vehicle
- Normal HEPES assay buffer.
- Reported limits
- No numerical bepotastine concentration series is tabulated; no dose series reconstructed from the curve. Drug stock solvent and lot-specific stereochemical purity are not specified in the read materials section.
Methods and source locations
Compound reported in the paper: Bepotastine besilate; Compound label in the paper: Bepotastine
Applies to the reported besilate material and intact-cell binding assay; does not validate the catalog lot.
Table 1, p. 71 (bepotastine row); Fig. 4b and caption, p. 73; Materials and Methods, pp. 67–68
Displacement of 5 nM [3H]mepyramine from intact-cell H1 receptors: One-site fit to displacement curves; binding measured for 120 min at 4°C after washing pretreated cells. — Table 1, p. 71 (bepotastine row); Fig. 4b and caption, p. 73; Materials and Methods, pp. 67–68