2012 Fiscal Year Final Research Report
Effects of anesthesia-related substance orexin on respiratory neurons in the isolated brainstem-spinal cord preparation of newborn rats
| Project/Area Number |
23791732
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Anesthesiology/Resuscitation studies
|
|---|
| Research Institution | Kanagawa Dental College |
|---|
Principal Investigator |
|
|---|
| Project Period (FY) |
2011 – 2012
|
| Keywords | 呼吸中枢 / 吸入麻酔薬 / オレキシン |
|---|
| Research Abstract |
Inhibitory effects of volatile anesthetic on respiratory activities are induced through its effects on central respiratory control. Past papers indicates that volatile anesthetic are though to induce aneshetic effects by its effects on GABA receptor. However, endogeneous neuropeptide orexin is recently believed to play an important role in sleep/wakefukness of anesthesia. Thus, this project analyse effects of orexin on central respiratory control using brainstem-spinal cord preparation of newborn rats. The application of Orexin B resulted in dose-dependent increases in C4 burst rate via brainstem, not via spinal cord. The increases in C4 burst rate induced concomitant increases in the depolarizing cycle rate of preinspiratory (Pre-I) neurons and inspiratory (Insp) neurons. The rhythmic bursts of C4 and Pre-I neurons finally became to be tonic, although the rhythmic bursts of Insp neurons were maintained. Expiratory (Exp) neurons were also depolarized by the application of Orexin B. Our findings indicate that Orexin B activates central respiratory activity mainly through depolarizing and increases in membrane resistance of Pre-I neurons and Insp neurons, and possibly through early start of expiratry phase induced by depolarization of Exp neurons.
|
