Fluorescence imaging of active respiratory networks.
Breathing in mammals is controlled by neural networks in the brainstem such as the pre-Bötzinger complex (preBötC) and the parafacial respiratory group (pFRG). Exploring these rhythmogenic networks and their interactions is greatly facilitated by live fluorescence imaging that enables analysis of (i) spatiotemporal patterns of respiratory (population) activities, (ii) (sub)cellular signaling in identified respiratory neurons, and (iii) membrane properties of respiratory neurons that are fluorescence-tagged for characteristic markers. Transversal medullary slices containing the preBötC and "en bloc" brainstem-spinal cord preparations with a functional preBötC/pFRG dual respiratory center which interacts, e.g., with pontine structures, are used for respiratory imaging in perinatal rodents. Imaging of less reduced (mature) respiratory networks is feasible in arterially-perfused "working-heart-brainstem" preparations from rodents. In these in situ models, imaging with voltage and Ca2+ sensitive dyes is established for assessment of respiratory (population) activities. Here, we summarize findings from diverse live imaging approaches in these models and point out potential pitfalls and future perspectives of respiratory-related optical recording.
Ruangkittisakul
Araya
A
Department of Physiology, University of Alberta, Edmonton, AB T6G 2S2, Canada.
Okada
Yasumasa
Y
Oku
Yoshitaka
Y
Koshiya
Naohiro
N
Ballanyi
Klaus
K
D000818:Animals; D002118:Calcium / Q000378:metabolism; D003952:Diagnostic Imaging; D008526:Medulla Oblongata / Q000166:cytology / Q000502:physiology; D009415:Nerve Net / Q000033:anatomy & histology / Q000502:physiology*; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology; D009474:Neurons / Q000502:physiology; D012119:Respiration; D012125:Respiratory Center / Q000033:anatomy & histology* / Q000502:physiology
D002118:Calcium