In vitro visualization of respiratory neuron activity in the newborn mouse ventral medulla.
To clarify the neuronal organization of the respiratory center of the mouse, we analyzed the spatio-temporal pattern of respiratory neuron activity in the ventral medulla of a newborn mouse preparation, using optical recordings. We also demonstrated optical images of the respiratory activity of two different lines of knock-out mice (Tlx3-/-, Pbx3-/-) that exhibit respiratory failure leading to neonatal death from dysfunction of central respiratory neuron activity. In the wild type mice, the respiratory neuron activity in the para-facial region of the rostral medulla appeared prior to inspiratory activity in the more caudal ventrolateral medulla. This rostral to caudal activity pattern was basically preserved in Tlx3-/- mice though the activity was more dispersed and weaker than in the wild type mice. Such an activity pattern was not clearly detected in Pbx3-/- mouse preparations. The difference in the spatio-temporal pattern between Tlx3-/- and Pbx3-/- suggests different levels of functional disorder of the respiratory center.
Onimaru
Hiroshi
H
Department of Physiology, Showa University School of Medicine, Toyo 142-8555, Japan. oni@med.showa-u.ac.jp
Arata
Akiko
A
Arata
Satoru
S
Shirasawa
Senji
S
Cleary
Michael L
ML
D000818:Animals; D000831:Animals, Newborn; D001933:Brain Stem / Q000166:cytology / Q000502:physiology; D004594:Electrophysiology; D018398:Homeodomain Proteins / Q000235:genetics; D008526:Medulla Oblongata / Q000166:cytology / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D009474:Neurons / Q000502:physiology*; D011518:Proto-Oncogene Proteins / Q000235:genetics; D012131:Respiratory Insufficiency / Q000235:genetics / Q000503:physiopathology; D015656:Respiratory Mechanics / Q000502:physiology*; D013050:Spectrometry, Fluorescence; D013116:Spinal Cord / Q000166:cytology / Q000502:physiology
D018398:Homeodomain Proteins; D011518:Proto-Oncogene Proteins; C487377:Tlx3 protein, mouse; C090466:proto-oncogene protein Pbx3