title: Effect of maternal care on hearing onset induced by developmental changes in the auditory periphery.
abstract: Handling (H) and cross-fostering (CF) rodent pups during postnatal development triggers changes in maternal behavior which in turn trigger long-term physiological changes in the offspring. However, less is known about the short-term effects of H and CF on infant development. In this study we hypothesized that manipulations of maternal care affect the onset of hearing in Wistar rats. To test this hypothesis we obtained auditory brainstem responses (ABRs) and micro-CT x-ray scans to measure changes in the development of the auditory periphery in H and CF pups manipulated at postnatal day (P)1, P5, or P9. We found evidence of changes in hearing development in H and CF pups compared with naive pups, including changes in the percentage of animals with ABRs during development, a decrease in ABR thresholds between P13 and P15, and anatomical results consistent with an accelerated formation of the middle ear cavity and opening of the ear canal. Biochemical measurements showed elevated levels of thyroid hormone in plasma from naive and CF pups. These results provide evidence that manipulations of maternal care accelerate hearing onset in Wistar rats. Understanding the mechanisms by which maternal care affects hearing onset opens new opportunities to study experience-dependent development of mammalian hearing.
authors.affiliation: Departments of Biology and Biomedical Engineering, The City College of New York, New York, New York 10031.
authors.forename: Shana
authors.initials: S
authors.lastname: Adise
authors.forename: Aminat
authors.initials: A
authors.lastname: Saliu
authors.forename: Natalia
authors.initials: N
authors.lastname: Maldonado
authors.forename: Vivek
authors.initials: V
authors.lastname: Khatri
authors.forename: Luis
authors.initials: L
authors.lastname: Cardoso
authors.forename: Adrián
authors.initials: A
authors.lastname: Rodríguez-Contreras
mesh_terms: D000161:Acoustic Stimulation; D000367:Age Factors; D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D001306:Auditory Pathways / Q000254:growth & development* / Q000502:physiology; D003345:Corticosterone / Q000378:metabolism; D004423:Ear / Q000254:growth & development*; D004797:Enzyme-Linked Immunosorbent Assay; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D005260:Female; D006309:Hearing / Q000502:physiology*; D021621:Imaging, Three-Dimensional; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008425:Maternal Behavior; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D015898:Tomography Scanners, X-Ray Computed
chemical_list: D007334:Insulin-Like Growth Factor I; D003345:Corticosterone
keywords: auditory development; enrichment; experience-dependent development; middle-ear development; plasticity; thyroid hormone