| First Author | Ruangkittisakul A | Year | 2014 |
| Journal | Physiol Rep | Volume | 2 |
| Issue | 8 | PubMed ID | 25138790 |
| Mgi Jnum | J:277969 | Mgi Id | MGI:6276474 |
| Doi | 10.14814/phy2.12111 | Citation | Ruangkittisakul A, et al. (2014) Identification of the pre-Botzinger complex inspiratory center in calibrated "sandwich" slices from newborn mice with fluorescent Dbx1 interneurons. Physiol Rep 2(8) |
| abstractText | Inspiratory active pre-Botzinger complex (preBotC) networks produce the neural rhythm that initiates and controls breathing movements. We previously identified the preBotC in the newborn rat brainstem and established anatomically defined transverse slices in which the preBotC remains active when exposed at one surface. This follow-up study uses a neonatal mouse model in which the preBotC as well as a genetically defined class of respiratory interneurons can be identified and selectively targeted for physiological recordings. The population of glutamatergic interneurons whose precursors express the transcription factor Dbx1 putatively comprises the core respiratory rhythmogenic circuit. Here, we used intersectional mouse genetics to identify the brainstem distribution of Dbx1-derived neurons in the context of observable respiratory marker structures. This reference brainstem atlas enabled online histology for generating calibrated sandwich slices to identify the preBotC location, which was heretofore unspecified for perinatal mice. Sensitivity to opioids ensured that slice rhythms originated from preBotC neurons and not parafacial respiratory group/retrotrapezoid nucleus (pFRG/RTN) cells because opioids depress preBotC, but not pFRG/RTN rhythms. We found that the preBotC is centered ~0.4 mm caudal to the facial motor nucleus in this Cre/lox reporter mouse during postnatal days 0-4. Our findings provide the essential basis for future optically guided electrophysiological and fluorescence imaging-based studies, as well as the application of other Cre-dependent tools to record or manipulate respiratory rhythmogenic neurons. These resources will ultimately help elucidate the mechanisms that promote respiratory-related oscillations of preBotC Dbx1-derived neurons and thus breathing. |
