Summary
Mechanical and electrical activity of the isolated guinea-pig taenia coli were recorded in bicarbonate-, Tris- or phosphate-buffered test solutions. In normal solution (pCO2 5%, pH 7.4), typical minute-rhythmical fluctuations of activity occurred, whereby activity was present for approximately 40% of the total time (active time), the other 60% being activity-free intervals. At constant extracellular pH, low CO2 content increased active time, high CO2 content reduced it. Extracellular alkalinization at constantpCO2 also diminished active time, even in CO2-free medium, whereas acidification raised it, sometimes causing continuous activity. At constant bicarbonate-buffer, changes of CO2 content, i.e. accompanied by corresponding changes in pH, affected the active time much less than did CO2 alterations in an isohydric medium. The test solutions had no major effect on frequency of synchronized spike discharges, in contrast to their actions on the minuterhythmical activity. Since CO2 can pass through the cell membrane more easily than ions regulating intra- and extracellular pH, the observed effects are best explained by changes in the transmembrane pH-gradient. A drop in active time would be due to a relative intracellular acidification; continuous activity, on the other hand, due to an opposite change in transmembrane pH-gradient, i.e. a relative intracellular alkalinization.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Adelmann, W. J., Jr.: Effect of hypocapnea on rhythmicity of isolated duodenum. Amer. J. Physiol.187, 582 (1956).
Bayliss, W. M.: The action of carbon dioxide on blood vessels. J. Physiol. (Lond.)26, 32–33 (1901).
Brown, E. B., Jr., Goott, B.: Intracellular hydrogen ion changes and potassium movement. Amer. J. Physiol.204, 765–770 (1963).
—, Kim, W. G., Moorhead, F. A., Jr.: Intracellular pH during metabolic acidosis of intracellular and extracellular origin. Proc. Soc. exp. Biol. (N.Y.)126, 595–599 (1967).
Golenhofen, K.: Slow rhythms in smooth muscle (minute-rhythm). In: Smooth muscle. Ed. by E. Bülbring et al. London: Arnold 1970.
—: Intrinsic rhythms of the gastrointestinal tract. In: Gastrointestinal motility. Ed. by L. Demling and R. Ottenjann. Stuttgart-New York-London: Thieme: Academic Press 1971.
—, Lammel, E.: Selective suppression of some components of spontaneous activity in various types of smooth muscle by iproveratril (verapamil). Pflügers Arch.331, 233–243 (1972).
—, v. Loh, D.: Elektrophysiologische Untersuchungen zur normalen Spontanaktivität der isolierten Taenia coli des Meerschweinchens. Pflügers Arch.314, 312–328 (1970a).
——: Intracelluläre Potentialmessungen zur normalen Spontanaktivität der isolierten Portalvene des Meerschweinchens. Pflügers Arch.319, 82–100 (1970b).
——, Milenov, K.: Elektrophysiologische Untersuchungen zur Spontanaktivität isolierter Muskelpräparate aus verschiedenen Abschnitten des Meerschweinchen-Magens. Pflügers Arch.315, 336–356 (1970).
Holman, M. E.: Introduction to electrophysiology of visceral smooth muscle. Handbook of Physiology, Alimentary Canal IV, pp. 1665–1708. Washington: Amer. Physiol. Soc. 1968.
Ishikawa, H.: Die Erweiterung der Gefäße in tätigen Organen. Z. allg. Physiol.16, 223–264 (1914).
Löhr, H.: Untersuchungen zur Physiologie und Pharmakologie der Lunge. Z. ges. exp. Med.39, 67–130 (1924).
Loeschcke, H. H., Katsaros, B.: Die Wirkung von in den Liquor cerebrospinalis eingebrachtem Ammoniumchlorid auf Atmung und Vasomotorik. Pflügers Arch. ges. Physiol.270, 147–160 (1959).
v. Loh, D., Golenhofen, K.: Temperatureinflüsse auf die Spontanaktivität der isolierten Taenia coli vom Meerschweinchen. Pflügers Arch.318, 35–50 (1970).
McSwiney, B. A., Newton, W. H.: Reaction of smooth muscle to the H-ion concentration. J. Physiol. (Lond.)63, 51–60 (1927).
Meves, H.: Die Wirkung von Kohlensäure auf lebende Gewebe. Heidelberg: Hüthig 1958.
Pearce, R. G.: Studien über antagonistische Nerven. VIII. Untersuchungen zur Dynamik der Gefäßverengung und-erweiterung und über die Umkehr peripherer Erregung in Hemmung. Z. Biol.62, 243–294 (1913).
Roos, A.: Intracellar pH and buffering power of rat brain. Amer. J. Physiol.221, 176–181 (1971).
—: Intracellular pH and buffering power of rat muscle. Amer. J. Physiol.221, 182–188 (1971).
Tobin, R. B.: Plasma, extracellular and muscle electrolyte responses to acute metabolic acidosis. Amer. J. Physiol.186, 131–138 (1956).
Vaughan Williams, E. M.: The individual effects of CO2, bicarbonate and pH on the electrical and mechanical activity of isolated rabbit auricles. J. Physiol. (Lond.)129, 90–110 (1955).
Waddell, W. J., Bates, R. G.: Intracellular pH. Physiol. Rev.49, 285–329 (1969).
—, Butler, T. C.: Calculation of intracellular pH from the distribution of 5,5-dimethyl-2,4-oxazolidinedione (DMO). Application to skeletal muscle of the dog. J. clin. Invest.38, 720–729 (1959).
Wienbeck, M., Golenhofen, K., Lammel, E.: Der Effekt von CO2 auf die Spontanaktivität von isolierter glatter Muskulatur (Taenia coli des Meerschweinchens). Pflügers Arch. ges. Physiol.300, 78 (1968).
Wilson, A. F., Simmons, D. H.: Organ and whole body cell pH. Proc. Soc. exp. Biol. (N.Y.)134, 127–130 (1970).
Author information
Authors and Affiliations
Additional information
This work was supported by the Deutsche Forschungsgemeinschaft
Rights and permissions
About this article
Cite this article
Wienbeck, M., Golenhofen, K. & Lammel, E. The effects of CO2 and pH on the spontaneous activity of the taenia coli of guinea-pig. Pflugers Arch. 334, 181–192 (1972). https://doi.org/10.1007/BF00586790
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00586790