Previous studies showed that unilateral denervation (DNV) of the rat diaphragm muscle (DIAm) results in loss of myosin heavy chain protein by 1 day after DNV. We hypothesize that DNV decreases net protein balance as a result of activation of the ubiquitin-proteasome pathway. In DIAm strips, protein synthesis was measured by incorporation of 3H-Tyr, and protein degradation was measured by Tyr release at 1, 3, 5, 7, and 14 days after DNV. Total protein ubiquitination, caspase-3 expression/activity, and actin fragmentation were analyzed by Western analysis. We found that, at 3 days after DNV, protein synthesis increased by 77% relative to sham controls. Protein synthesis remained elevated at 5 (85%), 7 (53%), and 14 days (123%) after DNV. At 5 days after DNV, protein degradation increased by 43% relative to sham controls and remained elevated at 7 (49%) and 14 days (74%) after DNV. Thus, by 5 days after DNV, net protein balance decreased by 43% compared with sham controls and was decreased compared with sham at 7 (49%) and 14 days (72%) after DNV. Protein ubiquitination increased at 5 days after DNV and remained elevated.
http://jap.physiology.org/content/107/2/438.full
Monday, April 4, 2011
fall in the resting membrane potential (RMP) that was identical to the effect of surgical denervation
ACh blockade using a-BuTx produced a fall in the resting membrane potential (RMP) that was identical to the effect of surgical denervation with respect to the time of onset, rate of development, and extent of change. Blockade of nerve impulses using TTX produced a similar but partial change in the RMP that began later and progressed more slowly than that of denervation.
Similarly, the increase of extrajunctional ACh receptors following cY-BuTx-induced blockade of ACh transmission was identical to that of surgical denervation. By contrast, the effect of nerve impulse block using TTX was less pronounced at equivalent time points.
Our findings indicate that specific pharmacological blockade of ACh transmission produces
changes in the RMP and extrajunctional ACh receptors of skeletal muscle that are quantitatively equivalent to those of denervation. This suggests that ACh transmission itself mediates the nerve’s trophic regulation of these muscle properties.
The Journal of Neuroscience, Vol. 2, No. 2, pp. 232-243 . February 1982
The denervation effect of smooth muscles in this instance is related to the delayed response of the smooth muscle
The denervation effect of smooth muscles in this instance is related to the delayed response of the smooth muscles and not the effect of denervation.The result, however, is the same and the four components of denervation (super-duration/delayed response, hyper-excitability, increased susceptibility and super-reactivity) are mimicked exactly by inelastic and inflexible smooth muscles.
Autonomic nervous system: The autonomic nervous system of most fibromyalgia patients is imbalance with predominate excessive sympathetic outflows. The term dysautonomia is often used to describe these patients' S / S related to the ANS. There are significant problems related to smooth muscle dysfunctions (see effect of relaxin on smooth muscles) and the control of these organs as alluded to in the beginning of this discussion. This has to do with imbalance of the relatively increased sympathetic or decreased parasympathetic tone of the ANS. The inability of the ANS to maintain a homeostatic level of control on the smooth muscles and sphincters of many of the inner organs results in the under/ over performance of these organs.
http://www.encognitive.com/node/12690
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