Unit responses in the cat auditory cortex to electrical stimulation of nerve fibers innervating receptor cells in different parts of the organ of corti

Previous studies have suggested that activation of ATP-sensitive P2X receptors in skeletal muscle play a role in mediating the exercise pressor reflex (Li J and Sinoway LI. Am J Physiol Heart Circ Physiol 283: H2636–H2643, 2002). To determine the role ATP plays in this reflex, it is necessary to examine whether muscle interstitial ATP (ATPi) concentrations rise with muscle contraction. Accordingly, in this study, muscle contraction was evoked by electrical stimulation of the L7 and S1 ventral roots of the spinal cord in 12 decerebrate cats. Muscle ATPi was collected from microdialysis probes inserted in the muscle. ATP concentrations were determined by the HPLC method. Electrical stimulation of the ventral roots at 3 and 5 Hz increased mean arterial pressure by 13 ± 2 and 16 ± 3 mmHg ( P < 0.05), respectively, and it increased ATP concentration in contracting muscle by 150% ( P < 0.05) and 200% ( P < 0.05), respectively. ATP measured in the opposite control limb did not rise with ventral root stimulation. Section of the L7 and S1 dorsal roots did not affect the ATPi seen with 5-Hz ventral root stimulation. Finally, ventral roots stimulation sufficient to drive motor nerve fibers did not increase ATP in previously paralyzed cats. Thus ATPi is not largely released from sympathetic or motor nerves and does not require an intact afferent reflex pathway. We conclude that ATPi is due to the release of ATP from contracting skeletal muscle cells.

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Electrical Stimulation of Nerve Cells Using Conductive Nanofibrous Scaffolds for Nerve Tissue Engineering

Tissue Engineering Part A ◽

10.1089/ten.tea.2008.0689 ◽

2009 ◽

Vol 15 (11) ◽

pp. 3605-3619 ◽

Cited By ~ 199

Author(s):

Laleh Ghasemi-Mobarakeh ◽

Molamma P. Prabhakaran ◽

Mohammad Morshed ◽

Mohammad Hossein Nasr-Esfahani ◽

Seeram Ramakrishna

Keyword(s):

Tissue Engineering ◽

Electrical Stimulation ◽

Nerve Cells ◽

Nerve Tissue ◽

Nanofibrous Scaffolds ◽

Nerve Tissue Engineering ◽

Stimulation Of Nerve ◽

Stimulation Of

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Short-range stiffness of slow fibers and twitch fibers in reptilian muscle

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1976.231.2.449 ◽

1976 ◽

Vol 231 (2) ◽

pp. 449-453 ◽

Cited By ~ 10

Author(s):

U Proske ◽

PM Rack

Keyword(s):

Short Range ◽

Motor Nerve ◽

Nerve Fibers ◽

Repetitive Stimulation ◽

Fiber Types ◽

Cross Links ◽

Stimulation Of Nerve ◽

Limiting Value ◽

Stimulation Of

The semitendinous muscle of the lizard Tilique contains both slow and twitch fibers; by subdivision of its motor nerve, fibers of each type may be stimulated separately. When, during repetitive stimulation of nerve filaments, the muscle was lengthened or shortened, the tension changes included an initial short-range stiffness, followed by a later compliance. With increasing velocities of movement, the short-range stiffness increased toward a limiting value. For slow fibers this limiting value was reached with lower velocities of movement than for the twitch fibers. Provided that the same velocity of movement was used and the movements began from similar initial isometric tensions, the slow fibers resisted the movements with a greater stiffness than the twitch fibers. It is suggested that not all of the observed differences between the two fiber types can be interpreted simply in terms of differences in rates of formation and breakdown of cross-links.

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Relationships between permeable vessels, nerves, and mast cells in rat cutaneous neurogenic inflammation

Journal of Applied Physiology ◽

10.1152/jappl.1990.68.6.2305 ◽

1990 ◽

Vol 68 (6) ◽

pp. 2305-2311 ◽

Cited By ~ 42

Author(s):

J. N. Baraniuk ◽

M. L. Kowalski ◽

M. A. Kaliner

Keyword(s):

Electrical Stimulation ◽

Mast Cells ◽

Neurogenic Inflammation ◽

Sensory Nerve ◽

Nerve Fibers ◽

Sensory Nerves ◽

Neurokinin A ◽

Rat Skin ◽

Protein Extravasation ◽

Stimulation Of

Electrical stimulation of rat sensory nerves produces cutaneous vasodilation and plasma protein extravasation, a phenomenon termed “neurogenic inflammation”. Rat skin on the dorsum of the paw developed neurogenic inflammation after electrical stimulation of the saphenous nerve. In tissue sections, the extravasation of the supravital dye monastral blue B identified permeable vessels. Mast cells were identified by toluidine blue stain. Permeable vessels were significantly more dense in the superficial 120 microns of the dermis than in the deeper dermis, whereas mast cells were significantly more frequent in the deeper dermis. The relationships between nociceptive sensory nerve fibers, permeable vessels, and mast cells were examined by indirect immunohistochemistry for calcitonin gene-related peptide (CGRP), neurokinin A (NKA), and substance P (SP). CGRP-, NKA-, and SP-containing nerves densely innervated the superficial dermis and appeared to innervate the vessels that became permeable during neurogenic inflammation. In contrast, mast cells were not associated with either permeable vessels or nerve fibers. These data suggest that electrical stimulation of rat sensory nerves produces vascular permeability by inducing the release of neuropeptides that may directly stimulate the superficial vascular bed. Mast cells may not be involved in this stage of cutaneous neurogenic inflammation in rat skin.

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