Laudanosine has No Effects on Respiratory Activity but Induces Non-Respiratory Excitement Activity in Isolated Brainstem-Spinal Cord Preparation of Neonatal Rats
Laudanosine, a degradation of neuomuscular blocking agent atracurium, crosses the blood-brain barrier and is indicted to trigger seizures at high concentration. In Xenopus Oocytes expressing nicotinic acetylcholine receptors (nAChRs), laudanosine has activating and inhibiting effects on nAChRs depending on its concentration. nAChRs is related to respiratory activities and thus, in the present study, we analyzed effects of laudanosine on central respiratory activities using isolated brainstem-spinal cord preparation of neonatal rats. The rhythmic inspiratory burst activity of the C4 spinal ventral root was recorded using a glass suction electrode as an index of respiratory rate. After superfusion with mock cerebrospinal fluid (CSF), the preparation was superfused with mock CSF containing laudanosine 1, 10 or 100 μM for 60 minutes. Laudanosine 1, 10 and 100 μM (n = 10 in each) did not induce any effects on C4 respiratory rate. In all 10 preparations, laudnosine 100 μM induced non-respiratory excitement activities that are possibly same as seizure observed in vivo study.
KeywordsRespiratory Activity Neuromuscular Blocking Agent Vecuronium Bromide Neuronal nAChRs Inspiratory Discharge
This study was supported by a Grant-in-Aid for Young Scientist (SS).
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