|
|
||||||||
Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
We utilized cytochrome oxidase (CO) as a marker of neuronal functional activity to examine metabolic changes in brain stem respiratory nuclei of rats from newborn to 21 day of age. The pre-Bötzinger complex (PBC), upper airway motoneurons of nucleus ambiguus (NAUAM), ventrolateral nucleus of solitary tract (NTSVL), and medial and lateral parabrachial nuclei (PBM and PBL, respectively) were examined at postnatal days (P) 0, 1, 2, 3, 4, 5, 7, 14, and 21. CO histochemistry was performed, and the intensity of CO reaction product was quantitatively analyzed by optical densitometry. In addition, CO histochemistry was combined with neurokinin-1 receptor (NK1R) immunogold-silver staining to doubly label neurons of PBC in P14 animals. The results showed that levels of CO activity generally increased with age in all of the nuclei examined. However, a significant decrease was found in NAUAM at P3 (P < 0.01), and a distinct plateau of CO activity was noted at P3 in PBC and at P3 and P4 in NTSVL, PBM, and PBL. Of the neurons examined in PBC, 83% were doubly labeled with CO and NK1R. Of these, CO activity was high in 33.9%, moderate in 27.3%, and light in 38.8% of neurons, suggesting different energy demands in these metabolic groups that may be related to their physiological or synaptic properties. The transient decrease or plateau in CO activity at P3 and P4 implies a period of synaptic adjustment or reorganization during development, when there may be decreased excitatory synaptic drive or increased inhibitory synaptic drive, or both, in these brain stem respiratory nuclei. The adjustment, in turn, may render the system less responsive to respiratory insults. This may bear some relevance to our understanding of pathological events during postnatal development, such as occurs in sudden infant death syndrome.
neurokinin-1 receptor; nucleus ambiguus; nucleus of solitary tract; parabrachial nuclei; pre-Bötzinger complex
This article has been cited by other articles:
![]() |
Q. Liu, T. F. Lowry, and M. T. T. Wong-Riley Postnatal changes in ventilation during normoxia and acute hypoxia in the rat: implication for a sensitive period J. Physiol., December 15, 2006; 577(3): 957 - 970. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. Liu and M. T. T. Wong-Riley Developmental changes in the expression of GABAA receptor subunits {alpha}1, {alpha}2, and {alpha}3 in the rat pre-Botzinger complex J Appl Physiol, May 1, 2004; 96(5): 1825 - 1831. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. Liu and M. T. T. Wong-Riley Postnatal changes in cytochrome oxidase expressions in brain stem nuclei of rats: implications for sensitive periods J Appl Physiol, December 1, 2003; 95(6): 2285 - 2291. [Abstract] [Full Text] |
||||
![]() |
Q. Liu, J. Kim, J. Cinotte, P. Homolka, and M. T. T. Wong-Riley Carotid body denervation effect on cytochrome oxidase activity in pre-Botzinger complex of developing rats J Appl Physiol, March 1, 2003; 94(3): 1115 - 1121. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. L. Carroll Plasticity in Respiratory Motor Control: Invited Review: Developmental plasticity in respiratory control J Appl Physiol, January 1, 2003; 94(1): 375 - 389. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. Liu and M. T. T. Wong-Riley Postnatal expression of neurotransmitters, receptors, and cytochrome oxidase in the rat pre-Botzinger complex J Appl Physiol, March 1, 2002; 92(3): 923 - 934. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Serra, D. Brozoski, M. Hodges, S. Roethle, R. Franciosi, and H. V. Forster Effects of carotid and aortic chemoreceptor denervation in newborn piglets J Appl Physiol, March 1, 2002; 92(3): 893 - 900. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Serra, D. Brozoski, N. Hedin, R. Franciosi, and H. V. Forster Mortality after carotid body denervation in rats J Appl Physiol, September 1, 2001; 91(3): 1298 - 1306. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y.-Y. Liu, G. Ju, and M. T. T. Wong-Riley Distribution and colocalization of neurotransmitters and receptors in the pre-Botzinger complex of rats J Appl Physiol, September 1, 2001; 91(3): 1387 - 1395. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |