Effect of JM-1232(-), a New Sedative on Central Respiratory Activity in Newborn Rats
JM-1232(-), a newly manufactured isoindole derivative, shows sedative effect at a lower concentration compared with propofol. In the present study, we analyzed the response of the central respiratory activity to JM-1232(-). The brainstem-spinal cord of a newborn rat was isolated and was continuously superfused with oxygenated artificial cerebrospinal fluid (ACSF). Rhythmic inspiratory burst activity was recorded from C4 spinal ventral root using a glass suction electrode. We measured C4 burst rate and amplitude of integrated C4 activity. After obtaining a control recording, the preparation was superfused with ACSF containing JM-1232(-) at 10, 100 or 500 μM for 10 min. The application of both 10 and 100 μM JM-1232(-) did not decrease C4 burst rate significantly. However, 500 μM JM-1232(-) reduced C4 burst rate. On the contrary, C4 burst amplitude was not affected by the application of JM-1232(-) for 10 min at any concentrations. In conclusion, JM-1232(-) at a low concentration (but presumably higher than hypnotic dose), did not depress the central respiratory activity, whereas at a high concentration depression was seen.
KeywordsRespiratory Depression Ventral Root Artificial Cerebrospinal Fluid Anesthetic Dose Hypnotic Dose
This work was Supported by Japan Society for the Promotion of Science KAKENHI (18791106 to Dr. Kuribayashi and 19603015 to Dr. Kuwana), Tokyo, Japan