Journal
JOURNAL OF APPLIED PHYSIOLOGY
Volume 94, Issue 4, Pages 1421-1430Publisher
AMER PHYSIOLOGICAL SOC
DOI: 10.1152/japplphysiol.00599.2002
Keywords
central control of breathing; short-term potentiation; bistability; bulbospinal pathways
Categories
Funding
- NHLBI NIH HHS [HL/NS-60097, HL/NS-40336] Funding Source: Medline
Ask authors/readers for more resources
Respiratory afferent stimulation can elicit increases in respiratory motor output that outlast the period of stimulation by seconds to minutes [short-term potentiation (STP)]. This study examined the potential contribution of spinal mechanisms to STP in anesthetized, vagotomized, paralyzed rats. After C-1 spinal cord transection, stimulus trains (100 Hz, 5-60 s) of the C-1-C-2 lateral funiculus elicited STP of phrenic nerve activity that peaked several seconds poststimulation. Intracellular recording revealed that individual phrenic motoneurons exhibited one of three different responses to stimulation: 1) depolarization that peaked several seconds poststimulation, 2) depolarization during stimulation and then exponential repolarization after stimulation, and 3) bistable behavior in which motoneurons depolarized to a new, relatively stable level that was maintained after stimulus termination. During the STP, excitatory postsynaptic potentials elicited by single-stimulus pulses were larger and longer. In conclusion, repetitive activation of the descending inputs to phrenic motoneurons causes a short-lasting depolarization of phrenic motoneurons, and augmentation of excitatory postsynaptic potentials, consistent with a contribution to STP.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available