Association between T102C 5-HT2A receptor gene polymorphism and 5-year mortality risk among Brazilian Amazon riparian elderly population.

Objective: Serotonin (5-HT) is a pleiotropic molecule that exerts several functions on brain and peripheral tissues via different receptors. The gene for the 5-HT2A receptor shows some variations, including a T102C polymorphism, that have been associated with increased risk of neuropsychiatric and vascular disorders. However, the potential impact of 5-HT2A imbalance caused by genetic variations on the human lifespan has not yet been established.

Strain- and context-dependent behavioural responses of acute alarm substance exposure in zebrafish.

We investigate the behavioural responses of wild type (WT) and leopard (leo) zebrafish elicited by alarm substances of conspecifics at three contexts: during the exposure period (Experiment 1); after exposure, in habituation to novelty (Experiment 2); or after exposure, in the light-dark preference test (Experiment 3), and analyse their influence on pigment response. During the exposure, leo showed decreased vertical drifts, increased number and duration of erratic movements, while WT had increased erratic movements and latency to enter the top. In the novel tank, we observed that angular velocity decreased in WT exposed to alarm substance, which also presented increased fear responses.