Learn More
1. The effects of substance P (SP), acting at NK1 receptors, on the excitability and inspiratory activity of hypoglossal (XII) motoneurons (MNs) were investigated using rhythmically active medullary-slice preparations from neonatal mice (postnatal day 0-3). 2. Local application of the NK1 agonist [SAR(9),Met (O(2))(11)]-SP (SP(NK1)) produced a(More)
Multiple brainstem sites are proposed to contribute to central respiratory chemosensitivity, however, the underlying molecular mechanisms remain unknown. P2X2 subunit-containing ATP receptors, which mediate pH-sensitive currents, appear to contribute to central chemosensitivity in vivo [J. Physiol. 523 (2000) 441]. However, recent data from P2X2 knockout(More)
Hypoglossal (XII) motoneurons (MNs) contribute to diverse behaviors. Their innervation of the genioglossus muscle, a tongue protruder, plays a critical role in maintaining upper airway patency during breathing. Indeed, reduced activity in these motoneurons is implicated in sleep related disorders of breathing such as obstructive sleep apnea (OSA). The(More)
Neuronal input-output functions are traditionally studied using rectangular or ramp waveforms of injected current. These waveforms are easy to produce and responses to them easy to quantify; thus they have been central to our understanding of the roles that membrane properties play in controlling repetitive firing. However, since smooth rectangular step and(More)
1. Motoneurons (MN) shape motor patterns by transforming inputs into action potential output. This transformation, excitability, is determined by an interaction between synaptic inputs and intrinsic membrane properties. Excitability is not static, but changes over multiple time scales. The purpose of the present paper is to review our recent data on(More)
We examined developmental changes in breathing pattern and the ventilatory response to hypoxia (7.4% O(2)) in unanesthetized Swiss CD-1 mice ranging in age from postnatal day 0 to 42 (P(0)-P(42)) using head-out plethysmography. The breathing pattern of P(0) mice was unstable. Apneas were frequent at P(0) (occupying 29 +/- 6% of total time) but rare by P(3)(More)