170149-76-5

The in vivo binding of [³H]Mepyramine to mouse spinal cord and cerebellar histamine H₁ receptors is dose-dependently inhibited by ReN 1869. ReN 1869 (in doses as low as 10 μg/kg i.p.) significantly inhibits the histamine-evoked paw edema. The ED₅₀ is approximately 300 μg/kg. Interestingly, even a high dose of Mepyramine (10 mg/kg) is unable to inhibit significantly this type of edema (0.29±0.06 versus 0.34±0.05 in controls, n=7).ReN 1869 (1 mg/kg s.c.) is administered 30 min before paw injection with carrageenan and has no effect on the development of the paw edema. Dexamethasone (1 mg/kg s.c.) is given 1 h before carrageenan and expectedly diminished the edema. This effect is not affected by the simultaneous administration of 1 mg/kg ReN 1869^[1].