Hypertension during chronic exposure to cold: Comparison between Sprague Dawley (SD) and Long Evans (LE) strains

Conference · Mon Mar 11 00:00:00 EST 1991 · FASEB Journal (Federation of American Societies for Experimental Biology); (United States)

OSTI ID:5374753

Riesselmann, A; Baron, A; Fregly, M J ^[1]

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1. Univ. of Florida, Gainesville (United States)

Hypertension accompanies chronic exposure of SD rats to cold (5-6C), including elevation of systolic, diastolic, and mean blood pressures and cardiac hypertrophy. The renin-angiotensin system may play an important role. Earlier studies suggested that the LE strain may have a decrease in angiotensin I converting enzyme (ACE) activity. Measurement of ACE activity in plasmas of SE and LE strains revealed that basal activity of ACE in the plasma of the LE strain was significantly less than that of the SD strain. A second study was carried out in which both strains were exposed to cold for 7 weeks. There were clear differences between strains. Rats of the SD strain had a significant elevation in their blood pressure; a significantly increased urinary output of norepinephrine (NE) and epinephrine (E); and significant increases in weights of heart, kidneys, adrenals, and brown adipose tissue (IBAT) compared to their controls maintained at 26C. In contrast, rats of the LE strain were less responsive to cold in that blood pressure failed to rise as sharply and to attain as high a level; NE and E outputs, as well as weights of heart and IBAT were significantly less than those of rats of the cold-treated SD strain. Thus, the lower ACE activity in plasma of LE strain, as well as a reduced secretion of catecholamines, may protect these rats against the rise of blood pressure characteristically observed when rats of the SD strain are exposed to cold.

• OSTI ID: 5374753
• Report Number(s): CONF-9104107-; CODEN: FAJOE
• Journal Information: FASEB Journal (Federation of American Societies for Experimental Biology); (United States), Vol. 5:4; Conference: 75. annual meeting of the Federation of American Societies for Experimental Biology (FASEB), Atlanta, GA (United States), 21-25 Apr 1991; ISSN 0892-6638
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
HYPERTENSION
PATHOGENESIS
HYPOTHERMIA
BIOLOGICAL EFFECTS
PEPTIDE HYDROLASES
ENZYME ACTIVITY
RATS
BLOOD PRESSURE
ADRENALINE
CATECHOLAMINES
CHRONIC EXPOSURE
GENETIC VARIABILITY
NORADRENALINE
RENIN
TEMPERATURE EFFECTS
ADRENAL HORMONES
AMINES
ANIMALS
AROMATICS
AUTONOMIC NERVOUS SYSTEM AGENTS
BIOLOGICAL VARIABILITY
BODY TEMPERATURE
CARDIOTONICS
CARDIOVASCULAR AGENTS
CARDIOVASCULAR DISEASES
DISEASES
DRUGS
ENZYMES
HORMONES
HYDROLASES
HYDROXY COMPOUNDS
MAMMALS
NEUROREGULATORS
NONSPECIFIC PEPTIDASES
ORGANIC COMPOUNDS
PHENOLS
POLYPHENOLS
PROTEINS
RODENTS
SYMPATHOMIMETICS
SYMPTOMS
VASCULAR DISEASES
VERTEBRATES
560200* - Thermal Effects