Faculty Collaboration Database

Postnatal developmental changes in CO2 sensitivity in rats. J Appl Physiol (1985) 2006 Oct;101(4):1097-103

Date

06/24/2006

Pubmed ID

16794027

DOI

10.1152/japplphysiol.00378.2006

Scopus ID

2-s2.0-33749350208   52 Citations

Abstract

Ventilatory sensitivity to CO(2) in awake adult Brown Norway (BN) rats is 50-75% lower than in adult Sprague-Dawley (SD) and salt-sensitive Dahl S (SS) rats. The purpose of the present study was to test the hypothesis that this difference would be apparent during the development of CO(2) sensitivity. Four litters of each strain were divided into four groups such that rats were exposed to 7% inspired CO(2) for 5 min in a plethysmograph every third day from postnatal day (P) 0 to P21 and again on P29 and P30. From P0 to P14, CO(2) exposure increased pulmonary ventilation (Ve) by 25-50% in the BN and SD strains and between 25 to over 200% in the SS strain. In all strains beginning around P15, the response to CO(2) increased progressively reaching a peak at P19-21 when Ve during hypercapnia was 175-225% above eucapnia. There were minimal changes in CO(2) sensitivity between P21 and P30, and at both ages there were minimal between-strain differences. At P30, the response to CO(2) in the SS and SD strains was near the adult response, but the response in the BN rats was 100% greater at P30 than in adults. We conclude that 1) CO(2)-sensing mechanisms, and/or mechanisms downstream from the chemoreceptors, change dramatically at the age in rats when other physiological systems are also maturing ( approximately P15), and 2) there is a high degree of age-dependent plasticity in CO(2) sensitivity in rats, which differs between strains.

Author List

Davis SE, Solhied G, Castillo M, Dwinell M, Brozoski D, Forster HV

Authors

Melinda R. Dwinell PhD Professor in the Physiology department at Medical College of Wisconsin
Hubert V. Forster PhD Professor in the Physiology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Administration, Inhalation
Animals
Animals, Newborn
Animals, Outbred Strains
Carbon Dioxide
Hypercapnia
Plethysmography, Whole Body
Pulmonary Ventilation
Rats
Rats, Inbred BN
Rats, Inbred Dahl
Rats, Inbred Strains
Rats, Sprague-Dawley
Respiratory System
Species Specificity