Linked Life Data

15761088

Source:http://linkedlifedata.com/resource/pubmed/id/15761088

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2005-7-22
pubmed:abstractText
It is well known that hyperosmolality suppresses thermoregulatory responses and that plasma osmolality (P(osmol)) increases with exercise intensity. We examined whether the decreased esophageal temperature thresholds for cutaneous vasodilation (TH(FVC)) and sweating (TH(SR)) after 10-day endurance training (ET) are caused by either attenuated increase in P(osmol) at a given exercise intensity or blunted sensitivity of hyperosmotic suppression. Nine young male volunteers exercised on a cycle ergometer at 60% peak oxygen consumption rate (V(O2 peak)) for 1 h/day for 10 days at 30 degrees C. Before and after ET, thermoregulatory responses were measured during 20-min exercise at pretraining 70% V(O2 peak) in the same environment as during ET under isoosmotic or hyperosmotic conditions. Hyperosmolality by approximately 10 mosmol/kgH2O was attained by acute hypertonic saline infusion. After ET, V(O2 peak) and blood volume (BV) both increased by approximately 4% (P < 0.05), followed by a decrease in TH(FVC) (P < 0.05) but not by that in TH(SR). Although there was no significant decrease in P(osmol) at the thresholds after ET, the sensitivity of increase in TH(FVC) at a given increase in P(osmol) [deltaTH(FVC)/deltaP(osmol), degrees C x (mosmol/kgH2O)(-1)], determined by hypertonic infusion, was reduced to 0.021 +/- 0.005 from 0.039 +/- 0.004 before ET (P < 0.05). The individual reductions in deltaTH(FVC)/deltaP(osmol) after ET were highly correlated with their increases in BV around TH(FVC) (r = -0.89, P < 0.005). In contrast, there was no alteration in the sensitivity of the hyperosmotic suppression of sweating after ET. Thus the downward shift of TH(FVC) after ET was partially explained by the blunted sensitivity to hyperosmolality, which occurred in proportion to the increase in BV.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
99
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
237-43
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Ten-day endurance training attenuates the hyperosmotic suppression of cutaneous vasodilation during exercise but not sweating.
pubmed:affiliation
Dept. of Sports Medical Sciences, Shinshu Univ. Graduate School of Medicine, Matsumoto, Japan.
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, Non-U.S. Gov't