Grant: Operating Grant

Respiratory instabilities and apneas are a major cause of hospitalisation and morbidity in infants born prematurely. Smoking and drug abuse by the mother during pregnancy are significant risk factors for such respiratory disorders. However, respiratory problems related to abnormal function or immaturity of the brain regions that generate and regulate respiratory activity still occur in infants born to mothers that do not use such substances. The factors contributing to respiratory disorders in this population of newborn are still poorly understood. Stress and anxiety during pregnancy is a significant risk factor for the emergence of neurological diseases. While gestational stress is linked to poor birth outcome and increased need for resuscitation in newborn, the potential effect of gestational stress on respiratory activity in newborn is unknown. To address this issue, this proposal will use a clinically relevant rat model to determine whether exposing female rats to a stressful stimulus (fox odour) during pregnancy disturbs the function and development of the neural circuits that regulate breathing in the newborn. Specifically, we will measure apneas and respiratory instabilities along with the breathing responses to changes in blood oxygen and carbon dioxyde, and the presence of liquid in the airways of newborn pups. By studying these effects in different age groups, we will determine whether gestational stress also interferes with normal development of relevant respiratory responses and reflexes. Preliminary data are highly promising and we anticipate that the results from this research will help explain the occurrence of these respiratory disorders in the newborn. This is an important step in the development of prevention and treatment of this highly vulnerable population.