[Effect of prenatal alcohol exposure on rhythmic respiratory discharge activity in medullary slices of neonatal rats].

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.