Estrogen Supplementation Decreases Norepinephrine-Induced Vasoconstriction and Total Body Norepinephrine Spillover in Perimenopausal Women

Hypertension ◽  
1997 ◽  
Vol 30 (6) ◽  
pp. 1538-1543 ◽  
Author(s):  
Krishnankutty Sudhir ◽  
Murray D. Esler ◽  
Garry L. Jennings ◽  
Paul A. Komesaroff
Keyword(s):  
Perimenopausal Women ◽  
Total Body ◽  
Norepinephrine Spillover

scholarly journals Estrogen supplementation decreases total body norepinephrine spillover in perimenopausal women

1996 ◽  
Vol 27 (2) ◽  
pp. 219
Author(s):  
Krishnankutty Sudhir ◽  
Murray D. Esler ◽  
Garry L. Jennings ◽  
Paul A. Komesaroff
Keyword(s):  
Perimenopausal Women ◽  
Total Body ◽  
Norepinephrine Spillover

Pulmonary clearance and release of norepinephrine and epinephrine in newborn lambs

1997 ◽  
Vol 273 (1) ◽  
pp. L264-L274 ◽  
Author(s):  
J. J. Smolich ◽  
H. S. Cox ◽  
G. Eisenhofer ◽  
M. D. Esler
Keyword(s):  
Cesarean Section ◽  
Sympathetic Nerve ◽  
Sympathetic Nerve Activity ◽  
Plasma Epinephrine ◽  
Nerve Activity ◽  
Major Site ◽  
Vascular Catheters ◽  
Total Body ◽  
Norepinephrine Spillover ◽  
Kinetics Of

To examine the pulmonary kinetics of the catecholamines norepinephrine and epinephrine immediately after birth, eight fetal lambs were instrumented with vascular catheters under general anesthesia at 133-134 days gestation (term = 147 days) and were delivered by cesarean section 1 wk later. Pulmonary norepinephrine and epinephrine kinetics were then studied 1 and 4 h after birth using radiotracer dilution methodology. The pulmonary fractional extraction of norepinephrine was similar in 1-h (0.111 +/- 0.021) and 4-h (0.117 +/- 0.023) lambs and constituted 24 +/- 5 and 32 +/- 9% of total body norepinephrine clearance, respectively. Pulmonary removal of epinephrine was less pronounced with a fractional extraction of 0.035 +/- 0.017 in 1-h and 0.036 +/- 0.013 in 4-h lambs, which corresponded to 8 +/- 4 and 9 +/- 3% of total body epinephrine clearance, respectively. Pulmonary spillover of norepinephrine into the circulation was similar in 1-h (79 +/- 26 ng.min-1.kg-1) and 4-h (82 +/- 18 ng.min-1.kg-1) lambs, and this comprised 27 +/- 8 and 42 +/- 8% of total body norepinephrine spillover, respectively. Pulmonary epinephrine spillover was not detectable at 1 h, but it occurred in all 4-h lambs, averaging 4.7 +/- 0.8 ng.min-1.kg-1 or 20 +/- 6% of epinephrine total body spillover. These findings indicate that the lungs of newborn lambs 1) are a major site for removal of norepinephrine and epinephrine from the circulation; 2) release a substantial quantity of norepinephrine into the circulation, consistent with the presence of tonic pulmonary sympathetic nerve activity; and 3) constitute a significant extra-adrenal source of plasma epinephrine.

Contribution of lungs to desipramine-induced changes in whole body catecholamine kinetics in newborn lambs

1999 ◽  
Vol 276 (1) ◽  
pp. R243-R250 ◽  
Author(s):  
Joseph J. Smolich ◽  
Helen S. Cox ◽  
Murray D. Esler
Keyword(s):  
Cesarean Section ◽  
Spinal Anesthesia ◽  
Isotope Dilution ◽  
Whole Body ◽  
Major Portion ◽  
Newborn Period ◽  
Total Body ◽  
Norepinephrine Spillover ◽  
Induced Changes

To characterize pulmonary and total body norepinephrine and epinephrine kinetics in the immediate newborn period, the effects of desipramine were studied in six fetal lambs chronically instrumented at 133–134 days gestation (term 147 days) and delivered 1 wk later by cesarean section under spinal anesthesia. Norepinephrine and epinephrine kinetics were determined with isotope dilution methodology 4 h after birth and repeated 30 min after desipramine (2 mg/kg iv). At baseline, the lungs accounted for 35 ± 10 and 47 ± 13% of whole body norepinephrine clearance (93 ± 8 ml ⋅ min−1 ⋅ kg−1) and spillover (188 ± 29 ng ⋅ min−1 ⋅ kg−1) and 15 ± 2 and 19 ± 7% of whole body epinephrine clearance (82 ± 4 ml ⋅ min−1 ⋅ kg−1) and release (22.7 ± 2.7 ng ⋅ min−1 ⋅ kg−1), respectively. Desipramine decreased pulmonary norepinephrine and epinephrine clearance and spillover to near-zero levels, whereas whole body norepinephrine clearance fell by 51 ± 3% ( P < 0.001), norepinephrine spillover by 54 ± 6% ( P < 0.005), epinephrine clearance by 30 ± 6% ( P < 0.01), and epinephrine spillover by 34 ± 11% ( P < 0.05). These results indicate that, in the immediate newborn period, pulmonary removal and release of norepinephrine and epinephrine is mediated by a desipramine-sensitive process that accounts for a major portion of associated reductions in whole body norepinephrine and epinephrine clearance and release.

scholarly journals Norepinephrine Spillover from Human Adipose Tissue before and after a 72-Hour Fast

2002 ◽  
Vol 87 (7) ◽  
pp. 3373-3377 ◽  
Author(s):  
J. N. Patel ◽  
S. W. Coppack ◽  
D. S. Goldstein ◽  
J. M. Miles ◽  
G. Eisenhofer
Keyword(s):  
Adipose Tissue ◽  
Human Adipose Tissue ◽  
Sympathetic Nerves ◽  
Dilution Technique ◽  
Before And After ◽  
Adipose Tissue Lipolysis ◽  
Total Body ◽  
Norepinephrine Spillover ◽  
First Time ◽  
Tissue Norepinephrine

Adipose tissue lipolysis is at least in part stimulated by the sympathetic nervous system (SNS). Although there is a generalized decrease in SNS activity with fasting, the rate of lipolysis during fasting increases. The aim of this study was to determine whether there is an association between activation of sympathetic nerves innervating adipose tissue and the increase in lipolysis seen during fasting in humans. We used the isotope dilution technique to measure regional norepinephrine spillover from abdominal sc adipose tissue from seven healthy subjects before and after a 72-h fast. Our results showed a significant increase in adipose tissue spillover of norepinephrine (mean ± sem, 0.40 ± 0.09 vs. 1.08 ± 0.18 pmol·100 g−1·min−1, P &lt; 0.05) and arterial norepinephrine concentrations (0.92 ± 0.10 vs. 1.23 ± 0.08 nmol·liter−1, P &lt; 0.05) after the fast with no significant change in total body norepinephrine spillover, forearm norepinephrine spillover, epinephrine concentrations, or energy expenditure. We show for the first time, in humans, a selective regional increase in adipose tissue norepinephrine spillover in response to a 72-h fast and suggest that the SNS may play a greater role in the regulation of lipid metabolism during fasting than previously thought.

Norepinephrine spillover at rest and during submaximal exercise in young and old subjects

1997 ◽  
Vol 82 (6) ◽  
pp. 1869-1874 ◽  
Author(s):  
Robert S. Mazzeo ◽  
Chakravarthi Rajkumar ◽  
Garry Jennings ◽  
Murray Esler
Keyword(s):  
Age Groups ◽  
Work Capacity ◽  
Young Group ◽  
Submaximal Exercise ◽  
Whole Body ◽  
Plasma Norepinephrine ◽  
Clearance Rates ◽  
Young Subjects ◽  
Total Body ◽  
Norepinephrine Spillover

Mazzeo, Robert S., Chakravarthi Rajkumar, Garry Jennings, and Murray Esler. Norepinephrine spillover at rest and during submaximal exercise in young and old subjects. J. Appl. Physiol. 82(6): 1869–1874, 1997.—Aging is associated with elevations in plasma norepinephrine concentrations. The purpose of this investigation was to examine total body and regional norepinephrine spillover as an indicator of sympathetic nerve activity. Eight young (26 ± 3 yr) and seven old (69 ± 5 yr) male subjects were studied at rest and during 20 min of submaximal cycling exercise at 50% of peak work capacity. Norepinephrine spillover was determined by continuous intravenous infusion of [3H]norepinephrine. Arterial norepinephrine concentrations were significantly greater at rest for old vs. young subjects (280 ± 36 vs. 196 ± 27 ng/ml, respectively). Whereas total norepinephrine spillover did not differ between groups at rest, hepatomesenteric norepinephrine spillover was 50% greater in old subjects compared with their young counterparts (51 ± 7 vs. 34 ± 5 ng/min, respectively). Additionally, norepinephrine clearance rates at rest were significantly lower for the old subjects (−23%). During exercise, plasma norepinephrine concentrations increased compared with rest, with old subjects again demonstrating greater values than the young group. Hepatomesenteric norepinephrine spillover was significantly greater (+36%) during exercise for old subjects compared with young; however, no difference was found for whole body spillover rates between age groups. Norepinephrine clearance rates remained depressed (−30%) in the old subjects during exercise. Clearance of epinephrine mirrored that for norepinephrine both at rest and during exercise across age groups. It was concluded that in old subjects, a reduction in norepinephrine clearance and an increase in regional norepinephrine spillover can account for the higher plasma norepinephrine concentrations observed at rest. This relationship is not exacerbated by the stress imposed during an acute bout of exercise.

Fine Structural Changes in the Microvasculature of the Mouse Pinna: Aging and Radiation Injury

1974 ◽  
Vol 32 ◽  
pp. 54-55
Author(s):  
S. Phyllis Steamer ◽  
Rosemarie L. Devine
Keyword(s):  
Structural Changes ◽  
Radiation Treatment ◽  
Arterial Stenosis ◽  
Ultrastructural Changes ◽  
Vascular Effects ◽  
Microvascular Changes ◽  
Surrounding Connective Tissue ◽  
Fission Neutrons ◽  
Total Body

The importance of radiation damage to the skin and its vasculature was recognized by the early radiologists. In more recent studies, vascular effects were shown to involve the endothelium as well as the surrounding connective tissue. Microvascular changes in the mouse pinna were studied in vivo and recorded photographically over a period of 12-18 months. Radiation treatment at 110 days of age was total body exposure to either 240 rad fission neutrons or 855 rad 60Co gamma rays. After in vivo observations in control and irradiated mice, animals were sacrificed for examination of changes in vascular fine structure. Vessels were selected from regions of specific interest that had been identified on photomicrographs. Prominent ultrastructural changes can be attributed to aging as well as to radiation treatment. Of principal concern were determinations of ultrastructural changes associated with venous dilatations, segmental arterial stenosis and tortuosities of both veins and arteries, effects that had been identified on the basis of light microscopic observations. Tortuosities and irregularly dilated vein segments were related to both aging and radiation changes but arterial stenosis was observed only in irradiated animals.

The Fine Structure of Irradiated Mouse Heart

1976 ◽  
Vol 34 ◽  
pp. 184-185
Author(s):  
Vivian V. Yang ◽  
S. Phyllis Stearner
Keyword(s):  
Microscopic Level ◽  
Ultrastructural Changes ◽  
Mouse Heart ◽  
Blood Vessel Wall ◽  
Histopathological Changes ◽  
Light Microscopic Level ◽  
Γ Rays ◽  
Fission Neutrons ◽  
Total Body

The heart is generally considered a radioresistant organ, and has received relatively little study after total-body irradiation with doses below the acutely lethal range. Some late damage in the irradiated heart has been described at the light microscopic level. However, since the dimensions of many important structures of the blood vessel wall are submicroscopic, investigators have turned to the electron microscope for adequate visualization of histopathological changes. Our studies are designed to evaluate ultrastructural changes in the mouse heart, particularly in the capillaries and muscle fibers, for 18 months after total-body exposure, and to compare the effects of 240 rad fission neutrons and 788 rad 60Co γ-rays.Three animals from each irradiated group and three control mice were sacrificed by ether inhalation at 4 days, and at 1, 3, 6, 12, and 18 months after irradiation. The thorax was opened and the heart was fixed briefly in situwith Karnofsky's fixative.

Experimental study of total body washout employing extracorporeal circulation and hypothermia

1974 ◽  
Vol 126 (2) ◽  
pp. 243-248
Author(s):  
A WAKABAYASHI ◽  
T KUBO ◽  
K CHARNEY ◽  
Y NAKAMURA ◽  
J CONNOLLY
Keyword(s):  
Experimental Study ◽  
Extracorporeal Circulation ◽  
Total Body

Total Body Photography Helps Reduce Unnecessary Biopsies

2008 ◽  
Vol 39 (4) ◽  
pp. 20
Author(s):  
SHARON WORCESTER
Keyword(s):  
Total Body
Sign in / Sign up

Export Citation Format

Share Document