Activity of rat pump neurons is modulated with central respiratory rhythm.
The firing properties of the second-order neurons of the slowly-adapting pulmonary stretch receptors called pump neurons (P-cells), were studied in Nembutal-anesthetized, paralyzed, and artificially-ventilated rats. Extracellular recording was made from single P-cells which were monosynaptically activated by electrical stimulation of the vagal afferents and fired in phase with lung inflations. In the majority of the P-cells examined (49/52), the firing was suppressed to various extents in the inspiratory phase: in effect, their firing was accentuated at the time of the inspiratory off-switch. This issue has never been reported in cat P-cells, on which relatively rich data have been accumulated. The present results suggest that rat P-cells do not only relay information from the lung stretch receptors but also integrate the central respiratory inputs.
Department of Neurobiology, Tokyo Metropolitan Institute for Neuroscience, Fuchu, Japan.
M
M
Miyazaki
A
A
Arata
I
I
Tanaka
K
K
Ezure
D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D004558:Electric Stimulation; D008168:Lung / Q000502:physiology*; D008465:Mechanoreceptors / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012119:Respiration / Q000502:physiology*; D017552:Solitary Nucleus / Q000166:cytology / Q000502:physiology*; D014630:Vagus Nerve / Q000502:physiology