Implications of Polymorphisms in the CRHR1 Gene on the Hypothalamic-Pituitary-Adrenal Axis Functioning in Postpartum Depression

Abstract

Abstract Objective: This study was aimed at assessing the association of the TAT haplotype of the corticotropinreleasing hormone receptor type 1 (CRHR1) with the function of the hypothalamic-pituitaryadrenal (HPA) axis in depressive and euthymic women in the remote postpartum period. Methods: The sample (mean age = 27.9 ± 5.3 years) consisted of 37 depressed postpartum women, of which 26 had one or two copies of the TAT haplotype (D-TAT1/2) and 11 had no TAT haplotype (D-TAT0), and 41 euthymic postpartum women, being 21 with one or two copies of the TAT haplotype (E-TAT1/2) and 20 without the TAT haplotype (E-TAT0). Salivary cortisol samples were collected immediately upon awakening and 30 minutes, 3 hours and 12 hours later, approximately in the sixth month after delivery (mean = 169.6 ± 60.3 days). DNA for genotyping was extracted between 22 and 25 weeks of pregnancy. Results: D-TAT1/2 women presented lower cortisol awakening response (CAR) compared with E-TAT1/2 and E-TAT0 women. Independently of the diagnosis of depression, only women with at least one copy of the TAT haplotype presented a negative correlation between CAR and scores of perceived stress during pregnancy and depressive symptoms in the postpartum. Conclusion: The association between CRHR1 polymorphisms and postpartum depression may be mediated by variability in individual responses to stress as assessed through HPA axis responsiveness.