Abstract: Objective To investigate the effects of prenatal alcohol exposure on rhythmic respiratory discharge activity (RRDA)
in the medullary slices of neonatal rats. Methods Ten pregnant female SD rats were exposed to 0, 4%, 6%, 8%, and 10% alcohol
in drinking water from 1 week before till 3 days after delivery. The medullary slices of the neonatal rats containing the medial
region of the nucleus retrofacialis (mNRF) with the hypoglossal nerve rootlets were prepared and perfused with modified
Kreb’s solution to record RRDA from the hypoglossal nerve rootlets using suction electrodes. Results No significant difference
was found in RRDA in 50 min among the neonatal rats with prenatal exposure to 0, 4%, 6%, and 8% alcohol, but the RRDA in
10% alcohol exposure group became irregular. Prenatal exposure to increased alcohol concentrations caused attenuated RRDA
attenuated in the neonatal rats, shown by shortened inspiratory time (TI), decreased respiratory frequency (RF), and reduced
integral amplitude (IA) as compared with those in the control group. Conclusion Prenatal alcohol exposure inhibits RRDA in
medullary slices of neonatal rats, which might be a mechanism by which maternal alcohol exposure causes suppressed
offspring respiratory functions.