AJP - Cell Physiology, Vol 264, Issue 2 C419-C429, Copyright © 1993 by American Physiological Society

ARTICLES

Calcitonin gene-related peptide stimulates active Na(+)-K+ transport in rat soleus muscle

S. L. Andersen and T. Clausen
Institute of Physiology, University of Aarhus, Denmark.

Calcitonin gene-related peptide (CGRP) is found in a wide variety of tissues, including sensory and motor nerve endings in skeletal muscle. After intense electrical stimulation or K(+)-induced depolarization, CGRP can be released from nerve terminals and bound to receptors on sarcolemma. We show here that CGRP (rat and human) and salmon calcitonin stimulate 22Na extrusion and the influx of 86Rb and 42K in isolated rat soleus muscle. This leads to a pronounced (up to 56%) decrease in intracellular Na+, a minor increase in intracellular K+, and hyperpolarization. All these effects were blocked by ouabain or cooling, indicating that they reflect an acute stimulation of active electrogenic Na(+)-K+ transport. Capsaicin, which induces release of CGRP from sensory nerve endings, was found to exert similar effects on Na(+)-K+ transport. Various Na(+)-K+ pump-stimulating agents have been shown to counteract the inhibitory effect of a high extracellular concentration of K+ ([K+]o) on muscle contractility (4, 20). CGRP and capsaicin were likewise found to improve contractile performance of muscles inhibited by high [K+]o, and these effects were blocked by ouabain. CGRP might play a role in the maintenance of Na(+)-K+ gradients and excitability during intensive muscle work, known to be associated with an acute rise in the interstitial K+ concentration.

This article has been cited by other articles:

				N. Nordsborg, J. Ovesen, M. Thomassen, M. Zangenberg, C. Jons, F. M. Iaia, J. J. Nielsen, and J. Bangsbo Effect of dexamethasone on skeletal muscle Na+,K+ pump subunit specific expression and K+ homeostasis during exercise in humans J. Physiol., March 1, 2008; 586(5): 1447 - 1459. [Abstract] [Full Text] [PDF]

				G. Avila, C. I. Aguilar, and R. Ramos-Mondragon Sustained CGRP1 receptor stimulation modulates development of EC coupling by cAMP/PKA signalling pathway in mouse skeletal myotubes J. Physiol., October 1, 2007; 584(1): 47 - 57. [Abstract] [Full Text] [PDF]

				T. Clausen and O. B. Nielsen Potassium, Na+,K+-pumps and fatigue in rat muscle J. Physiol., October 1, 2007; 584(1): 295 - 304. [Abstract] [Full Text] [PDF]

				A. K. Hansen, T. Clausen, and O. B. Nielsen Effects of lactic acid and catecholamines on contractility in fast-twitch muscles exposed to hyperkalemia Am J Physiol Cell Physiol, July 1, 2005; 289(1): C104 - C112. [Abstract] [Full Text] [PDF]

				T. CLAUSEN Na+-K+ Pump Regulation and Skeletal Muscle Contractility Physiol Rev, October 1, 2003; 83(4): 1269 - 1324. [Abstract] [Full Text] [PDF]

				C. Yensen, W. Matar, and J.-M. Renaud K+-induced twitch potentiation is not due to longer action potential Am J Physiol Cell Physiol, July 1, 2002; 283(1): C169 - C177. [Abstract] [Full Text] [PDF]

				K. Overgaard and O. B. Nielsen Activity-induced recovery of excitability in K+-depressed rat soleus muscle Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2001; 280(1): R48 - R55. [Abstract] [Full Text] [PDF]

				O. M. Sejersted and G. Sjogaard Dynamics and Consequences of Potassium Shifts in Skeletal Muscle and Heart During Exercise Physiol Rev, October 1, 2000; 80(4): 1411 - 1481. [Abstract] [Full Text] [PDF]

				C. Juel, J. J. Nielsen, and J. Bangsbo Exercise-induced translocation of Na+-K+ pump subunits to the plasma membrane in human skeletal muscle Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2000; 278(4): R1107 - R1110. [Abstract] [Full Text] [PDF]

				A. P. Harrison and J. A. Flatman Measurement of force and both surface and deep M wave properties in isolated rat soleus muscles Am J Physiol Regulatory Integrative Comp Physiol, December 1, 1999; 277(6): R1646 - R1653. [Abstract] [Full Text] [PDF]

				C. Juel, Y. Hellsten, B. Saltin, and J. Bangsbo Potassium fluxes in contracting human skeletal muscle and red blood cells Am J Physiol Regulatory Integrative Comp Physiol, January 1, 1999; 276(1): R184 - R188. [Abstract] [Full Text] [PDF]