Rupatadine Fumarate

[3H]-Pyrilamine binding to histamine (H1) receptors in guinea pig cerebellum membranes

Antagonists were incubated with guinea pig cerebellum membranes (0.6 mg/mL) and [3H]-pyrilamine (1.2 nM) in 0.5 mL 50 mM PBS, pH 7.5, for 30 mins at 25 °C. The incubation was ended by the addition of 5 mL of ice-cold PBS containing 2 μM Pyrilamine and the collection of membranes was on Whatman GF/B filters. Then the filters were washed with 3 × 5 mL of ice-cold PBS plus 2 μM Pyrilamine and transferred to counting vials. The radioactivity retained by each filter was measured by liquid scintillation counting in 3 mL of HiSafe 3. Specific binding was determined from the difference between the [3H]-pyrilamine bound in the absence and in the presence of a large molar excess (10 μM) of unlabeled Promethazine.

Cell lines

Platelets

Preparation method

The solubility of this compound in warm ethanol is > 12.6 mg/mL. General tips for obtaining a higher concentration: Please warm the tube at 37 °C for 10 minutes and/or shake it in the ultrasonic bath for a while. Stock solution can be stored below - 20 °C for several months.

Reacting condition

Up to 100 μM; 5 mins

Applications

Rupatadine Fumarate competitively inhibited platelet-activating factor (PAF)-induced platelet aggregation in washed rabbit platelets (pA2 = 6.68 ± 0.08) and in human platelet-rich plasma (IC50 = 0.68 μM). However, Rupatadine Fumarate did not affect ADP- or arachidonic acid (AA)-induced platelet aggregation.

Animal models

Mice and rats

Dosage form

i.v. or p.o

Applications

Rupatadine Fumarate (i.v.) blocked histamine- and PAF-induced hypotension in rats with the ID50 values of 1.4 and 0.44 mg/kg, respectively. Moreover, Rupatadine Fumarate potently inhibited PAF-induced mortality in mice (ID50 = 0.31 and 3.0 mg/kg, respectively, for the i.v. and p.o. administrations) and endotoxin-induced mortality in mice and rats (ID50 = 1.6 and 0.66 mg/kg, respectively. i.v.).

Other notes

Please test the solubility of all compounds indoor, and the actual solubility may slightly differ with the theoretical value. This is caused by an experimental system error and it is normal.

References:

[1]. Merlos M, Giral M, Balsa D, Ferrando R, Queralt M, Puigdemont A, García-Rafanell J, Forn J. Rupatadine, a new potent, orally active dual antagonist of histamine and platelet-activating factor (PAF). J Pharmacol Exp Ther. 1997 Jan;280(1):114-21.