Ketamine Reduces Avoidance Responses During Re-Exposition to Aversive Stimulus: Comparison Between ()-Isomer and Racemic Mixture.

Background/objectives: Recent studies have investigated the effects of ketamine on fear memory in animals. However, it is unclear if ketamine might affect avoidance memory and emotional behaviors concomitantly. In this study, we compared the effects of (,)- and ()-ketamine in modulating avoidance responses, depression- and anxiety-related behaviors in stressed mice.

The alpha antagonist tamsulosin impairs memory acquisition, consolidation and retrieval in a novel object recognition task in mice.

Tamsulosin is an α-adrenoceptor antagonist used to treat benign prostatic hyperplasia. This drug exhibits high affinity for α- and α-adrenoceptor subtypes, which are also expressed in the brain. While dementia symptoms have been reported after administration of tamsulosin in humans, studies on its effects on the rodent brain are still rare.