Document Detail

The thyroid and hypoxic moderation of systemic hypertension in the spontaneously hypertensive rat.
MedLine Citation:
PMID:  3606517     Owner:  NLM     Status:  MEDLINE    
Surgically thyroidectomized (TX), sham-operated euthyroid (EU), or thyroidectomized with dietary hormone replacement (RPL), 8-week-old male spontaneously hypertensive rats were subjected to 4 weeks of either of two altitude treatments: normoxia (N; lab altitude = 1520 m) or hypobaric hypoxia (H; simulated altitude = 3658 m). Systolic blood pressure (SBP) was attenuated in all hypoxic and in TX-N rats (p less than 0.05). Thyroidectomy reduced oxygen consumption, rectal temperature, and hormonal indices of thyroid function, as well as attenuating hypoxia-induced polycythemia and right ventricular hypertrophy. Thyroidectomy decreased the sensitivity of aortic rings to KCl and isoproterenol with no differences between EU-N and EU-H or between TX-N and TX-H apparent. Vessel responsiveness in RPL-H was consistent with the hypothyroid status indicated by hormonal measurement, while RPL-N vessel responsiveness was characteristic of euthyroid vessels. Since EU-H rats were euthyroid, with similar vascular responses to EU-N, hypoxia-induced attenuation of SBP does not require hypothyroid-like vascular alterations. Thus, hypoxia and thyroidectomy appear to mitigate systemic hypertension by different mechanisms.
W N Henley; A Tucker; T N Tran; J M Stager
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Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  Aviation, space, and environmental medicine     Volume:  58     ISSN:  0095-6562     ISO Abbreviation:  Aviat Space Environ Med     Publication Date:  1987 Jun 
Date Detail:
Created Date:  1987-07-28     Completed Date:  1987-07-28     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  7501714     Medline TA:  Aviat Space Environ Med     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  559-67     Citation Subset:  IM; S    
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MeSH Terms
Hypertension / physiopathology*,  therapy
Oxygen / physiology*
Rats, Inbred SHR
Thyroid Gland / physiology*
Thyroid Hormones / physiology
Reg. No./Substance:
0/Thyroid Hormones; 7782-44-7/Oxygen

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

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