Modulation of Hypothalamic-pituitary-Adrenal Axis Parameters by Teneurin C-terminal Associated Peptide (TCAP)-1

Teneurin C-terminal associated peptides (TCAP) are a family of bioactive peptides found on the terminal exon of the four teneurin genes. TCAP-1 is found within brain regions that modulate the activity of corticotropin-releasing factor (CRF), which is the principal neuropeptide regulator of the hypothalamic-pituitary-adrenal (HPA) axis. TCAP-1 has suppressive effects on CRF-induced anxiety behaviours in rats. However, previous studies determined that TCAP-1 does not act directly on the CRF receptors (CRFR). Thus, I postulate that TCAP-1 may act centrally to modify elements of the HPA axis. Using an immortalized mouse hippocampal cell line, I tested the hypothesis that TCAP acts either downstream of CRFR activation, or on the regulation of the glucocorticoid receptors (GCR), which modulate CRF actions. These studies indicate that TCAP-1 represents a novel peptide in the regulation of stress related systems, which acts independently of either CRF-, or glucocorticoid- mediated signal transduction and transcription.MAS