Normal Anxiety, Fear and Depression-related Behaviors in Mice Lacking alpha-Calcitonin Gene-Related Peptide

ABSTRACT

Calcitonin gene-related peptide (CGRP) expressing neurons are distributed widely throughout the central and peripheral nervous systems. Due to its distribution and pharmacological studies, CGRP has been implicated to be involved in anxiety, fear and depression. In this study, alphaCGRP-knockout mice were used to assess the consequences of removing this neuropeptide to the mice behaviors. alphaCGRP-knockout mice performed equally as well as wild type mice in the light-dark transition test and in the elevated plus maze test of anxiety. alphaCGRP-null mice behaved similarly as wild-type mice in the Porsolt swim test of depression. They also exhibited normal learning and memory in the fear conditioning tasks. It is concluded that alphaCGRP is not essential for mice to be able to perform these tests, despite the presence of alphaCGRP in the relevant regions of the brain.