Fluorescent tagging of rhythmically active respiratory neurons within the pre-Bötzinger complex of rat medullary slice preparations.
Elucidation of the neuronal mechanisms underlying respiratory rhythmogenesis is a major focal point in respiratory physiology. An area of the ventrolateral medulla, the pre-Bötzinger complex (preBotC), is a critical site. Attention is now focused on understanding the cellular and network properties within the preBotC that underlie this critical function. The inability to clearly identify key "rhythm-generating" neurons within the heterogeneous population of preBotC neurons has been a significant limitation. Here we report an advancement allowing precise targeting of neurons expressing neurokinin-1 receptors (NK1Rs), which are hypothesized to be essential for respiratory rhythmogenesis. The internalization of tetramethylrhodamine conjugated substance P in rhythmically active medullary slice preparations provided clear visualization of NK1R-expressing neurons for subsequent whole-cell patch-clamp recordings. Among labeled neurons, 82% were inspiratory modulated, and 25% had pacemaker properties. We propose that this approach can be used to greatly expedite progress toward understanding the neuronal processes underlying the control of breathing.
Pagliardini
Silvia
S
Department of Physiology, Centre for Neuroscience, University of Alberta, Edmonton, Alberta, Canada T6G 2S2.
Adachi
Tadafumi
T
Ren
Jun
J
Funk
Gregory D
GD
Greer
John J
JJ
D000818:Animals; D005456:Fluorescent Dyes / Q000032:analysis*; D066298:In Vitro Techniques; D007553:Isotope Labeling / Q000379:methods; D008526:Medulla Oblongata / Q000737:chemistry* / Q000502:physiology; D015336:Molecular Probe Techniques; D015335:Molecular Probes / Q000032:analysis; D009474:Neurons / Q000737:chemistry* / Q000502:physiology; D010507:Periodicity; D051381:Rats; D017207:Rats, Sprague-Dawley; D018040:Receptors, Neurokinin-1 / Q000032:analysis / Q000502:physiology; D012119:Respiration; D015656:Respiratory Mechanics / Q000502:physiology*; D013373:Substance P / Q000032:analysis / Q000502:physiology
D005456:Fluorescent Dyes; D015335:Molecular Probes; D018040:Receptors, Neurokinin-1; D013373:Substance P