| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
AJP - Regulatory, Integrative and Comparative Physiology, Vol 273, Issue 1 433-R441, Copyright © 1997 by American Physiological Society
ARTICLES |
N. A. Ritucci, J. B. Dean and R. W. Putnam
Department of Physiology and Biophysics, Wright State University, Dayton, Ohio 45435, USA.
We investigated whether neurons in two chemosensitive areas of the medulla oblongata [nucleus of the solitary tract (NTS) and ventrolateral medulla (VLM)] respond to hypercapnia differently than neurons in two nonchemosensitive areas of the medulla oblongata [inferior olive (IO) and hypoglossal nucleus (Hyp)]. Medullary brain slices from preweanling Sprague-Dawley rats were loaded with 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein, and intracellular pH (pHi) was followed in individual neurons at 37 degrees C with the use of a fluorescence imaging system. Most neurons from the NTS and VLM did not exhibit pHi recovery when CO2 was increased from 5 to 10% at constant extracellular HCO3- concentration [extracellular pH (pHo) decreased approximately 0.3 pH unit] (hypercapnic acidosis). However, when CO2 was increased from 5 to 10% at constant pHo (isohydric hypercapnia), pHi recovery was seen. In contrast, all neurons from the IO and Hyp exhibited pHi recovery during hypercapnic acidosis. All pHi recovery in the four areas studied was inhibited by 1 mM amiloride and unaffected by 0.5 mM 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid. These data indicate that 1) pHi regulation differs between neurons in chemosensitive (NTS and VLM) and nonchemosensitive (IO and Hyp) areas of the medulla, 2) pHi recovery is due solely to Na+/H+ exchange in all four areas, and 3) Na+/H+ exchange is more sensitive to inhibition by extracellular acidosis in NTS and VLM neurons than in IO and Hyp neurons.
This article has been cited by other articles:
|
|
 |
|
  J. Zhuang, F. Xu, and D. T. Frazier Hyperventilation evoked by activation of the vicinity of the caudal inferior olivary nucleus depends on the fastigial nucleus in anesthetized rats J Appl Physiol, May 1, 2008; 104(5): 1351 - 1358. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Kanaan, R. M. Douglas, S. L. Alper, W. F. Boron, and G. G. Haddad Effect of chronic elevated carbon dioxide on the expression of acid-base transporters in the neonatal and adult mouse Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2007; 293(3): R1294 - R1302. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. M. Chernov, J. A. Daubenspeck, J. S. Denton, J. R. Pfeiffer, R. W. Putnam, and J. C. Leiter A computational analysis of central CO2 chemosensitivity in Helix aspersa Am J Physiol Cell Physiol, January 1, 2007; 292(1): C278 - C291. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. A. Ritucci, J. B. Dean, and R. W. Putnam Somatic vs. dendritic responses to hypercapnia in chemosensitive locus coeruleus neurons from neonatal rats Am J Physiol Cell Physiol, November 1, 2005; 289(5): C1094 - C1104. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. A. Ritucci, J. S. Erlichman, J. C. Leiter, and R. W. Putnam Response of membrane potential and intracellular pH to hypercapnia in neurons and astrocytes from rat retrotrapezoid nucleus Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2005; 289(3): R851 - R861. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. F. Boron Regulation of intracellular pH Advan Physiol Educ, December 1, 2004; 28(4): 160 - 179. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. W. Putnam, J. A. Filosa, and N. A. Ritucci Cellular mechanisms involved in CO2 and acid signaling in chemosensitive neurons Am J Physiol Cell Physiol, December 1, 2004; 287(6): C1493 - C1526. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. K. Mulkey, R. A. Henderson III, N. A. Ritucci, R. W. Putnam, and J. B. Dean Oxidative stress decreases pHi and Na+/H+ exchange and increases excitability of solitary complex neurons from rat brain slices Am J Physiol Cell Physiol, April 1, 2004; 286(4): C940 - C951. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. S. Erlichman, A. Cook, M. C. Schwab, T. W. Budd, and J. C. Leiter Heterogeneous patterns of pH regulation in glial cells in the dorsal and ventral medulla Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2004; 286(2): R289 - R302. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. CHESLER Regulation and Modulation of pH in the Brain Physiol Rev, October 1, 2003; 83(4): 1183 - 1221. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. B. Dean, D. K. Mulkey, A. J. Garcia III, R. W. Putnam, and R. A. Henderson III Neuronal sensitivity to hyperoxia, hypercapnia, and inert gases at hyperbaric pressures J Appl Physiol, September 1, 2003; 95(3): 883 - 909. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. K. Mulkey, R. A. Henderson III, R. W. Putnam, and J. B. Dean Hyperbaric oxygen and chemical oxidants stimulate CO2/H+-sensitive neurons in rat brain stem slices J Appl Physiol, September 1, 2003; 95(3): 910 - 921. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. Filosa and R. W. Putnam Multiple targets of chemosensitive signaling in locus coeruleus neurons: role of K+ and Ca2+ channels Am J Physiol Cell Physiol, January 1, 2003; 284(1): C145 - C155. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Nottingham, J. C. Leiter, P. Wages, S. Buhay, and J. S. Erlichman Developmental changes in intracellular pH regulation in medullary neurons of the rat Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2001; 281(6): R1940 - R1951. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. KIWULL-SCHONE, M. WIEMANN, S. FREDE, D. BINGMANN, K. J. WIRTH, U. HEINELT, H.-J. LANG, and P. KIWULL A Novel Inhibitor of the Na+/H+ Exchanger Type 3 Activates the Central Respiratory CO2 Response and Lowers the Apneic Threshold Am. J. Respir. Crit. Care Med., October 1, 2001; 164(7): 1303 - 1311. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Yao, X.-Q. Gu, R. M. Douglas, and G. G. Haddad Role of Na+/H+ exchanger during O2 deprivation in mouse CA1 neurons Am J Physiol Cell Physiol, October 1, 2001; 281(4): C1205 - C1210. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Holleran, M. Babbie, and J. S. Erlichman Ventilatory effects of impaired glial function in a brain stem chemoreceptor region in the conscious rat J Appl Physiol, April 1, 2001; 90(4): 1539 - 1547. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. C. Hempleman, T. A. Rodriguez, Y. A. Bhagat, and R. S. Begay Benzolamide, acetazolamide, and signal transduction in avian intrapulmonary chemoreceptors Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2000; 279(6): R1988 - R1995. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. I. Goldstein, J. M. Mok, C. M. Simon, and J. C. Leiter Intracellular pH regulation in neurons from chemosensitive and nonchemosensitive regions of Helix aspersa Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2000; 279(2): R414 - R423. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. E. Bebout and S. C. Hempleman Chronic hypercapnia resets CO2 sensitivity of avian intrapulmonary chemoreceptors Am J Physiol Regulatory Integrative Comp Physiol, February 1, 1999; 276(2): R317 - R322. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. S. Erlichman, A. Li, and E. E. Nattie Ventilatory effects of glial dysfunction in a rat brain stem chemoreceptor region J Appl Physiol, November 1, 1998; 85(5): 1599 - 1604. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. A. Ritucci, L. Chambers-Kersh, J. B. Dean, and R. W. Putnam Intracellular pH regulation in neurons from chemosensitive and nonchemosensitive areas of the medulla Am J Physiol Regulatory Integrative Comp Physiol, October 1, 1998; 275(4): R1152 - R1163. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Rentero, N. Bruandet, B. Milne, and L. Quintin Catechol activation in rat rostral ventrolateral medulla after systemic isocapnic metabolic acidosis Am J Physiol Regulatory Integrative Comp Physiol, August 1, 1998; 275(2): R350 - R356. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
