THE RELATIONSHIP OF THE SPLANCHNIC, HEPATIC AND RENAL CLEARANCE RATES TO THE METABOLIC CLEARANCE RATE OF CORTISOL IN CONSCIOUS SHEEP

1973 ◽  
Vol 56 (2) ◽  
pp. 285-294 ◽  
Author(s):  
B. A. PANARETTO ◽  
J. Y. F. PATERSON ◽  
F. HILLS
Keyword(s):  
Renal Clearance ◽  
Plasma Flow ◽  
Clearance Rate ◽  
Metabolic Clearance ◽  
Clearance Rates ◽  
Metabolic Clearance Rate ◽  
Flow Rates ◽  
Conscious Sheep ◽  
Relationship Of ◽  
The Relationship

SUMMARY The uptake of cortisol by organs in the splanchnic area of conscious, undisturbed sheep was estimated before and during the administration of adrenocorticotrophic hormone (ACTH) by measuring cortisol concentration differences in portal and hepatic venous plasma and estimating hepatic plasma flow rates. Metabolic clearance rates (MCR) of plasma cortisol were measured simultaneously. The total splanchnic clearance of cortisol was 61% of MCR in the animal, 48% being accounted for by the liver. When ACTH was given there were increases in MCR and these were accompanied by proportional increases in hepatic plasma flow rates. When ACTH was infused the total splanchnic clearance rate was 65% of MCR, 52–59% being accounted for by the liver. In other experiments the renal clearance rate of cortisol was studied. Under control conditions, and when ACTH was given, the renal clearance was 11% of MCR. The relationship of the sum of individual clearances to MCR is compared and discussed.

Inverse relationship of metabolic clearance rate of insulin to body mass index

Metabolism ◽  
1987 ◽  
Vol 36 (3) ◽  
pp. 219-222 ◽  
Author(s):  
Mayer B. Davidson ◽  
Michael D. Harris ◽  
Carol S. Rosenberg
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Clearance Rate ◽  
Inverse Relationship ◽  
Metabolic Clearance ◽  
Metabolic Clearance Rate ◽  
Relationship Of

METABOLIC CLEARANCE RATES OF PREGNENOLONE, 17-ACETOXYPREGNENOLONE AND THEIR SULPHATE ESTERS IN MAN AND IN RABBIT

1967 ◽  
Vol 39 (3) ◽  
pp. 395-403 ◽  
Author(s):  
D. Y. WANG ◽  
R. D. BULBROOK ◽  
F. ELLIS ◽  
M. M. COOMBS
Keyword(s):  
Clearance Rate ◽  
Metabolic Clearance ◽  
Dehydroepiandrosterone Sulphate ◽  
Clearance Rates ◽  
Metabolic Clearance Rate ◽  
Free Steroid

SUMMARY The metabolic clearance rates, distribution volumes and half-lives of pregnenolone, 17-acetoxypregnenolone and their sulphate esters were determined in man and in the rabbit. Pregnenolone was cleared about three times more quickly than pregnenolone sulphate in both species. The metabolic clearance rate of 17-acetoxypregnenolone sulphate is greater in the rabbit than in man, whether expressed in absolute terms or in relation to the metabolic clearance rate of the free steroid. The slow clearance rate of 17-acetoxypregnenolone sulphate in man is similar to that of testosterone sulphate, dehydroepiandrosterone sulphate and cholesterol sulphate; but is unlike that of pregnenolone sulphate, which is cleared approximately ten times as quickly.

THE METABOLIC CLEARANCE RATES OF DEHYDROEPIANDROSTERONE, TESTOSTERONE AND THEIR SULPHATE ESTERS IN MAN, RAT AND RABBIT

1967 ◽  
Vol 38 (3) ◽  
pp. 307-318 ◽  
Author(s):  
D. Y. WANG ◽  
R. D. BULBROOK ◽  
A. SNEDDON ◽  
T. HAMILTON
Keyword(s):  
Clearance Rate ◽  
Peripheral Circulation ◽  
Metabolic Clearance ◽  
Clearance Rates ◽  
Metabolic Clearance Rate

SUMMARY The disappearance of isotopically labelled dehydroepiandrosterone, testosterone and their sulphates from the peripheral circulation of man, rabbit and rat has been investigated. Metabolic clearance rates, distribution volumes and half-lives have been determined for these compounds in the above species. In man, the steroid sulphates have a much lower metabolic clearance rate than the corresponding free steroids. This large difference stems from longer half-lives and lower distribution volumes of the former. In the rabbit or rat the steroid sulphates and the appropriate free steroids do not show such marked differences in their metabolic clearance rates: the half-lives and distribution volumes are comparable.

RELATIONSHIP OF VISCERAL BLOOD FLOW TO CORTISOL METABOLISM IN COLD-STRESSED SHEEP

1974 ◽  
Vol 60 (2) ◽  
pp. 235-245 ◽  
Author(s):  
B. A. PANARETTO
Keyword(s):  
Blood Flow ◽  
Renal Clearance ◽  
Rectal Temperature ◽  
Plasma Cortisol ◽  
Whole Body ◽  
Metabolic Clearance ◽  
Clearance Rates ◽  
Cortisol Metabolism ◽  
Quantitative Changes ◽  
Relationship Of

SUMMARY Whole body metabolic clearance rates (MCR) and splanchnic, hepatic and renal clearance rates of cortisol were estimated in six shorn sheep under control conditions. The measurements were repeated in the same animals when they were exposed to a cold, wet environment while they were maintaining a normal rectal temperature and again when they became hypothermic, their mean final rectal temperature ( ~ 36 °C) having been reduced approximately 2–3 °C below the control range. The quantitative changes in MCR that occurred during cold stress were found to be associated with corresponding changes in splanchnic and renal clearance rates. Increases in plasma cortisol concentrations up to 50 μg/1 were accompanied by proportional increases in rates of splanchnic blood flow and cortisol clearance. When cortisol concentrations rose above 50 μg/1 in hypothermic animals the MCR values tended to fall because of reductions in hepatic and renal blood flow; very large increases in plasma cortisol concentrations then resulted from comparatively small increases in production rate.

scholarly journals Effect of ischaemic limb injury on the rates of metabolism of ketone bodies in starved rats

1976 ◽  
Vol 156 (2) ◽  
pp. 233-238 ◽  
Author(s):  
R N Barton
Keyword(s):  
Clearance Rate ◽  
Ketone Body ◽  
Ketone Bodies ◽  
Whole Body ◽  
Metabolic Clearance ◽  
O2 Consumption ◽  
Clearance Rates ◽  
Metabolic Clearance Rate ◽  
Limb Injury ◽  
Blood Ketone Bodies

1. Rats starved for 30h were injected with trace amounts of [3-14C]acetoacetate and β-hydroxy[3-14C]butyrate 1h after ischaemic limb injury in a 20 °C environment, and the concentrations and radioactivities of blood ketone bodies were determined at intervals. 2. Starvation alone raised the rates of production and utilization of β-hydroxybutyrate plus acetoacetate about 3.7-fold, but lowered their metabolic clearance rates by about 50%. In the starved rat ketone-body oxidation could account for up to 30% of whole body O2 consumption. 3. Injury in starved rats lowered the rates of production and utilization of both β-hydroxybutyrate and acetoacetate, the combined fall of about 37% slightly exceeding the concomitant fall in whole-body O2 consumption. The concentration of β-hydroxybutyrate decreased after injury, but its metabolic clearance rate was unaltered; the concentration of acetoacetate rose slightly and its metabolic clearance rate fell.

Biopotency in vitro and metabolic clearance rates of five pituitary preparations of follicle stimulating hormone

1993 ◽  
Vol 5 (2) ◽  
pp. 181 ◽  
Author(s):  
DJ Phillips ◽  
NL Hudson ◽  
S Lun ◽  
LA Condell ◽  
KP McNatty
Keyword(s):  
Clearance Rate ◽  
Polyacrylamide Gel Electrophoresis ◽  
Follicle Stimulating Hormone ◽  
Metabolic Clearance ◽  
Clearance Rates ◽  
Metabolic Clearance Rate ◽  
In Vitro Bioassay ◽  
Receptor Assay ◽  
Stimulating Hormone

Five pituitary preparations of follicle stimulating hormone (FSH), namely NIDDK-oFSH-17, Bioscan oFSH, Ovagen, Folltropin-V and F.S.H.-P., were examined for biological activity in terms of their potency in an in vitro bioassay, receptor assay and heterologous radioimmunoassay and in terms of their metabolic clearance rates. In the three assays, Bioscan oFSH was the most potent (P < 0.05) (3- to 5-fold the potency of NIDDK-oFSH-17), with Ovagen being 25-50% the potency of the NIDDK standard (P < 0.05). Folltropin-V and F.S.H.-P. had the lowest potencies in all three assays. For each preparation, the ratio of activities between the assays was not consistent, suggesting that the preparations behaved differently in each assay. In 9 of 10 cases, potency estimates in the heterologous radioimmunoassay were greater than those in the in vitro bioassay or receptor assay. Polyacrylamide gel electrophoresis of the preparations showed banding consistent with the molecular weight of FSH, but also indicated that the preparations were contaminated with other proteins to varying extents. The half-lives of these preparations when injected into the bloodstream of mature female mice were 28.0, 8.6, 13.4, 11.6 and 17.4 min for NIDDK-oFSH-17, Bioscan oFSH, Ovagen, Folltropin-V and F.S.H.-P. respectively. The slopes of the decay rates were significantly different from each other (P < 0.05) except between Ovagen and Folltropin-V. The results of these studies show that a number of widely available FSH preparations have differing biopotencies. Moreover, the biopotency of a preparation in vitro is not related to its metabolic clearance rate, and not all FSH preparations behave identically in different assays. Measures of biopotency in vitro combined with those of metabolic clearance rate may provide useful information on the properties of FSH preparations used for research purposes and for superovulation of farmed livestock.

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