Bioactivity | Scopolamine is a high affinity (nM) muscarinic antagonist. 5-HT3 receptor-responses are reversibly inhibited by Scopolamine with an IC50 of 2.09 μM. |
Invitro | Application of Scopolamine to oocytes expressing 5-HT3 receptors does not elicit a response when applied alone, but causes a concentration-dependent inhibition of the response during a co-application of 2 μM 5-HT. The pIC50 value for Scopolamine is 5.68±0.05 (IC50=2.09 μM, n=6) with a Hill Slope of 1.06 ± 0.05. This gave a Kb of 3.23 μM. The same concentration-dependent effect is also seen when Scopolamine is applied during the 5-HT application. To further test for a competitive binding at the 5-HT3 receptor, the competition of unlabelled Scopolamine is measured with [3H]granisetron, an established high-affinity competitive antagonist at these receptors. Scopolamine displays concentration-dependent competition with 0.6 nM [3H]granisetron (~Kd), yielding an average pKi of 5.17±0.24 (Ki=6.76 μM, n=3)[1]. |
Name | Scopolamine |
CAS | 51-34-3 |
Formula | C17H21NO4 |
Molar Mass | 303.35 |
Transport | Room temperature in continental US; may vary elsewhere. |
Storage | 4°C, sealed storage, away from moisture and light *In solvent : -80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture and light) |