title: PACAP receptor gene polymorphism impacts fear responses in the amygdala and hippocampus.
abstract: We have recently found higher circulating levels of pituitary adenylate cyclase-activating polypeptide (PACAP) associated with posttraumatic stress disorder (PTSD) symptoms in a highly traumatized cohort of women but not men. Furthermore, a single nucleotide polymorphism in the PACAP receptor gene ADCYAP1R1, adenylate cyclase activating polypeptide 1 receptor type 1, was associated with individual differences in PTSD symptoms and psychophysiological markers of fear and anxiety. The current study outlines an investigation of individual differences in brain function associated with ADCYAP1R1 genotype. Forty-nine women who had experienced moderate to high levels of lifetime trauma participated in a functional MRI task involving passive viewing of threatening and neutral face stimuli. Analyses focused on the amygdala and hippocampus, regions that play central roles in the pathophysiology of PTSD and are known to have high densities of PACAP receptors. The risk genotype was associated with increased reactivity of the amygdala and hippocampus to threat stimuli and decreased functional connectivity between the amygdala and hippocampus. The findings indicate that the PACAP system modulates medial temporal lobe function in humans. Individual differences in ADCYAP1R1 genotype may contribute to dysregulated fear circuitry known to play a central role in PTSD and other anxiety disorders.
authors: Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA 30322.
authors: Jennifer Strafford
authors: JS
authors: Stevens
authors: Lynn M
authors: LM
authors: Almli
authors: Negar
authors: N
authors: Fani
authors: David A
authors: DA
authors: Gutman
authors: Bekh
authors: B
authors: Bradley
authors: Seth D
authors: SD
authors: Norrholm
authors: Emily
authors: E
authors: Reiser
authors: Timothy D
authors: TD
authors: Ely
authors: Rahim
authors: R
authors: Dhanani
authors: Ebony M
authors: EM
authors: Glover
authors: Tanja
authors: T
authors: Jovanovic
authors: Kerry J
authors: KJ
authors: Ressler
mesh_terms: D000328:Adult; D001741:Black or African American / Q000235:genetics; D000679:Amygdala / Q000503:physiopathology*; D063132:Connectome; D005239:Fear / Q000502:physiology*; D005260:Female; D005838:Genotype; D006624:Hippocampus / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000097:blood / Q000378:metabolism; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I / Q000235:genetics* / Q000378:metabolism; D012737:Sex Factors; D013313:Stress Disorders, Post-Traumatic / Q000235:genetics* / Q000503:physiopathology
chemical_list: C495503:ADCYAP1R1 protein, human; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I
keywords: emotion; fMRI; intermediate phenotype; single nucleotide polymorphism