Bemesetron

Bemesetron (MDL 72222) is a selective 5-HT₃ receptor antagonist with an IC₅₀ of 0.33 nM^[1]. Neuroprotective effect^[2]. In Vitro: Blockade of 5-HT₃ receptor with Bemesetron (MDL7222) reduces hydrogen peroxide-induced neurotoxicity in cultured rat cortical cells. Bemesetron (0.01, 0.1 and 1 μM, 15 hours) and Y25130 (0.05, 0.5 and 5 μM) concentration-dependently reduce the H₂O₂-induced decrease of MTT reduction showing 74.9±2.4 and 79.0 ±2.5% with 1 μM and 5 μM, respectively, which are maximal effects^[2].
Pretreatment (20 minutes) with Bemesetron (1 μM), Y25130 (5 μM) or MK-801 (10 μM) significantly, but not completely, inhibits the H₂O₂-induced elevation of [Ca²⁺]_c^[2].
Bemesetron (1 μM, 15 hours) significantly blocks the H₂O₂-induced increase of caspase-3 immunoreactivity^[2].
In Vivo: Bemesetron (0.1, 1 and 10 mg/kg; i.p.) is used in male adult albino mice. The lowest dose do not cause any significant change in catalepsy. However, Bemesetron (1 mg/kg) causes a significant reduction of catalepsy (from 90 min after Haloperidol), while 10 mg/kg significantly potentiates the phenomenon (from 60 min after Haloperidol). The maximum inhibition of catalepsy (about 75%) occurs at 120 min, and the maximum potentiation (about 4.5-times the control value) occurs at 60 min after Haloperidol^[3].