Influence of diazepam on cocaine and amphetamine regulated transcript (CART) peptides in the telencephalon of zebrafish

Abstract

Although the role of cocaine and amphetamine regulated transcript (CART) in energy metabolism is well established, recent studies have shown its involvement in processing of anxiety. Diazepam is commonly used to treat anxiety in humans. Herein we investigate the response of the endogenous CART immunoreactive system in the telencephalon following treatment with this agent. Zebrafish has emerged as a useful alternative to screen a range of activities including anxiety. We have studied the change in distribution pattern of CART in the telencephalon of zebrafish following diazepam administration. No changes were observed in the entopeduncular nucleus (EN), central (Dc), dorsal (Dd) and medial (Dm) zones of the dorsal telencephalic area. The population of CART immunoreactive fibres was greater in the lateral zone of the dorsal telencephalic area (Dl) and preoptic area (POA) but smaller in the dorsal zone of the ventral telencephalic area (Vd). We suggest that the CART system in these areas may be involved in the regulation of anxiety‐like behaviour in zebrafish.