Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
6
|
pubmed:dateCreated |
1991-4-22
|
pubmed:abstractText |
The purpose of this study was to test the hypothesis that the cardiovascular-sympathetic nervous system adjustments during nonexertional heat stress are exaggerated in senescent (S, 24 mo) vs. mature (M, 12 mo) conscious unrestrained Fischer 344 rats. During two separate trials (48 h apart), each animal was exposed to an ambient temperature (Ta) of 42 degrees C until a colonic temperature (Tco) of 41 degrees C was attained and then cooled at a Ta of 26 degrees C until Tco returned to the initial control level. Trial 1: heart rate (HR), mean arterial blood pressure (MAP), and arterial plasma concentrations of norepinephrine (NE), epinephrine (E), and lactate (La) were similar between the S and M groups during the baseline (control) period. The absolute increases in HR, MAP, NE, and E from the control period to the end of heating were of similar magnitudes between groups; however, La increased more in the S than M animals (P less than 0.05). During recovery, the declines toward control levels for all variables were similar or even more rapid in the S vs. M animals (P less than 0.05). Trial 2: the changes in HR and MAP during heating were similar to those observed in trial 1 in both groups. Generally, NE and E control levels were elevated in both groups compared with those in trial 1. The absolute increases in NE during heating were similar to trial 1 in both groups, whereas E increased to a greater extent than in trial 1 in the S animals (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
|
pubmed:grant | |
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical | |
pubmed:status |
MEDLINE
|
pubmed:month |
Dec
|
pubmed:issn |
8750-7587
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:volume |
69
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
2043-9
|
pubmed:dateRevised |
2008-11-21
|
pubmed:meshHeading |
pubmed-meshheading:2076998-Acclimatization,
pubmed-meshheading:2076998-Aging,
pubmed-meshheading:2076998-Animals,
pubmed-meshheading:2076998-Blood Pressure,
pubmed-meshheading:2076998-Body Temperature,
pubmed-meshheading:2076998-Body Temperature Regulation,
pubmed-meshheading:2076998-Cardiovascular System,
pubmed-meshheading:2076998-Epinephrine,
pubmed-meshheading:2076998-Heart Rate,
pubmed-meshheading:2076998-Hot Temperature,
pubmed-meshheading:2076998-Lactates,
pubmed-meshheading:2076998-Male,
pubmed-meshheading:2076998-Norepinephrine,
pubmed-meshheading:2076998-Rats,
pubmed-meshheading:2076998-Rats, Inbred F344,
pubmed-meshheading:2076998-Stress, Physiological,
pubmed-meshheading:2076998-Sympathetic Nervous System
|
pubmed:year |
1990
|
pubmed:articleTitle |
Cardiovascular-sympathetic adjustments to nonexertional heat stress in mature and senescent Fischer 344 rats.
|
pubmed:affiliation |
Department of Exercise and Sport Sciences, University of Arizona, Tucson 85721.
|
pubmed:publicationType |
Journal Article,
Comparative Study,
Research Support, U.S. Gov't, P.H.S.
|