Urinary excretion rate of C-peptide in fed and fasted obese humans

R. Pasquali; P. Buratti; F. Casimirri; D. Patrono; M. Capelli; N. Melchionda; L. Barbara

doi:10.1530/acta.0.1180038

Urinary excretion rate of C-peptide in fed and fasted obese humans

Acta Endocrinologica ◽

10.1530/acta.0.1180038 ◽

1988 ◽

Vol 118 (1) ◽

pp. 38-44 ◽

Cited By ~ 1

Author(s):

R. Pasquali ◽

P. Buratti ◽

F. Casimirri ◽

D. Patrono ◽

M. Capelli ◽

...

Keyword(s):

Urinary Excretion ◽

B Cell ◽

Cell Function ◽

Excretion Rate ◽

Secretion Rate ◽

Urinary Excretion Rate ◽

Serum Samples ◽

Clearance Ratio ◽

Renal Metabolism ◽

C Peptide

Abstract. The aim of the study was to evaluate the reliability of urinary excretion rate of C-peptide as a marker of B-cell function during fasting. Ten obese subjects of both sexes fasted for 5 days. Diurnal serum C-peptide was collected before and on the 5th day; morning serum samples (for glucose, insulin and C-peptide) and 12-h urine samples (7.00 to 19.00 h) were collected daily. Body weight decreased from 138.7 ± 15.9 to 132.9 ± 15.6 kg. Morning glucose, insulin (–40%) and C-peptide (–50%) fell significantly throughout the study. Mean diurnal C-peptide values were 2.19 ±0.69 nmol/l before and 0.60 ±0.19 nmol/l after fasting (P < 0.0001) and its secretion rate was 909.4 ± 297.9 and 244.4 ± 83.9 nmol/12 h (P < 0.005), respectively. Excretion rate of C-peptide fell progressively from basal (11.2 ± 4.2 nmol/12 h) to a nadir value of 1.3 ± 0.8 nmol/12 h (P < 0.0005); similarly, the C-peptide to creatinine clearance ratio fell from 0.062 ± 0.035 to 0.028 ± 0.015 (P < 0.05). These results indicate that fasting modifies renal metabolism of C-peptide thus creating several complications in the quantitative interpretation of urinary levels as an index of its secretion rate from the B-cell.

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Estimation of the secretion rate of insulin from the urinary excretion rate of C-peptide. Study in obese and diabetic subjects

Diabetes ◽

10.2337/diabetes.31.5.449 ◽

1982 ◽

Vol 31 (5) ◽

pp. 449-453 ◽

Cited By ~ 23

Author(s):

M. T. Meistas ◽

M. Rendell ◽

S. Margolis ◽

A. A. Kowarski

Keyword(s):

Urinary Excretion ◽

Excretion Rate ◽

Secretion Rate ◽

Urinary Excretion Rate ◽

C Peptide

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Estimation of the Secretion Rate of Insulin from the Urinary Excretion Rate of C-Peptide: Study in Obese and Diabetic Subjects

Diabetes ◽

10.2337/diab.31.5.449 ◽

1982 ◽

Vol 31 (5) ◽

pp. 449-453 ◽

Cited By ~ 24

Author(s):

M. T. Meistas ◽

M. Rendell ◽

S. Margolis ◽

A. A. Kowarski

Keyword(s):

Urinary Excretion ◽

Excretion Rate ◽

Secretion Rate ◽

Urinary Excretion Rate ◽

C Peptide

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Urinary excretion rate of ceruloplasmin in non-insulin-dependent diabetic patients with different stages of nephropathy

Acta Endocrinologica ◽

10.1530/eje.0.1320681 ◽

1995 ◽

Vol 132 (6) ◽

pp. 681-687 ◽

Cited By ~ 14

Author(s):

Masatoshi Yamazaki ◽

Seiki Ito ◽

Akio Usami ◽

Nagayuki Tani ◽

Osamu Hanyu ◽

...

Keyword(s):

Urinary Excretion ◽

Excretion Rate ◽

University Hospital ◽

Tubular Function ◽

Dependent Diabetes Mellitus ◽

Diabetic Patients ◽

Urinary Excretion Rate ◽

Serum Samples ◽

Insulin Dependent ◽

Insulin Dependent Diabetic

Yamazaki M, Ito S, Usami A, Tani N, Hanyu 0, Nakagawa O. Nakamura H, Shibata A. Urinary excretion rate of ceruloplasmin in non-insulin-dependent diabetic patients with different stages of nephropathy. Eur J Endocrinol 1995;132:681–7. ISSN 0804–4643 The level of ceruloplasmin, which is a more negatively charged protein than albumin, was measured by an immunoradiometric assay in timed overnight urine and serum samples from patients with non-insulin-dependent diabetes mellitus and healthy controls. None of the plasma proteins examined showed any cross-reactivity in this assay. A linear correlation was seen between the ceruloplasmin level and the serial dilution of the sample. Western blot analysis using concentrated urine samples showed that the molecular weight of ceruloplasmin in the urine sample was the same as that of ceruloplasmin in the serum and standard samples. These findings indicated that the substance detected by this assay was truly ceruloplasmin. The urinary ceruloplasmin excretion rate (CER) and clearance of ceruloplasmin increased in parallel with the progression of albuminuria. The highest CER was found in macroalbuminuric patients, followed by micro- and normoalbuminuric patients and the healthy control subjects, the differences between the groups being significant. In view of the fact that the isoelectric point of ceruloplasmin (4.4) is more acidic than that of albumin, the present findings suggested that an enhanced CER was due either to the alteration of charge selectivity in the glomerular basement membrane with unaltered tubular function or to a defect of the non-discriminatory pores (shunt pathway) with unaltered tubular function. Seiki Ito, Division of Gerontology, Akita University Hospital, 1-1-1 Hondou, Akita City, Japan 010

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Direct Proportionality of Urinary Excretion Rate and Serum Level of Tetracycline in Human Subjects

Nature ◽

10.1038/198450a0 ◽

1963 ◽

Vol 198 (4879) ◽

pp. 450-453 ◽

Cited By ~ 28

Author(s):

T. CHULSKI ◽

R. H. JOHNSON ◽

C. A. SCHLAGEL ◽

J. G. WAGNER

Keyword(s):

Serum Level ◽

Urinary Excretion ◽

Excretion Rate ◽

Human Subjects ◽

Urinary Excretion Rate ◽

Direct Proportionality

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Compartmental transfer of mercury released from amalgam

Human & Experimental Toxicology ◽

10.1177/096032719701601107 ◽

1997 ◽

Vol 16 (11) ◽

pp. 667-672 ◽

Cited By ~ 5

Author(s):

S. Halbach ◽

L. Kremers ◽

H. Willruth ◽

A. Mehl ◽

G. Welzl ◽

...

Keyword(s):

Oral Cavity ◽

Urinary Excretion ◽

Total Mercury ◽

Excretion Rate ◽

Absorbed Dose ◽

Correlation Coefficients ◽

Urinary Excretion Rate ◽

Amalgam Fillings

The number of amalgam-covered surfaces and the occlusal area of the fillings, the concentrations of total mercury in plasma, erythrocytes and urine, the urinary excretion rate, and the absorbed daily doses estimated by two separate methods from intra-oral Hg emission were determined in 29 volunteers with a low amalgam load. The transfer ofHg from the fillings via the oral cavity and blood to urinary excretion was evaluated by multiple correla tions between these variables. In addition, the combina tion of variables most representative of the entire compartmental transfer of amalgam Hg was determined. Urinary excretion (1), Hg concentration in plasma (2) and absorbed dose (3) were most closely correlated to each other, followed by correlations with the variables of the fillings (4). Correlation coefficients were 0.75 for variables 1 vs 2 and 2 vs 3, and 0.49 for variables 3 vs 4. It was concluded that variables 1-3 best reflected the transfer of mercury from amalgam fillings throughout the organism and that they were relatively insensitive to dietary mercury. The determination of total mercury in plasma and of its urinary excretion rate appears, under practical aspects, most suitable for the investigation of Hg uptake from amalgam.

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1168 CORD PLASMA C-PEPTIDE/GLUCOSE [C-P/G] IN INFANTS OF DIABETIC MOTHERS [IDM]: RETROSPECTIVE AND PROSPECTIVE INDEX OF B-CELL FUNCTION

Pediatric Research ◽

10.1203/00006450-198104001-01194 ◽

1981 ◽

Vol 15 ◽

pp. 637-637

Author(s):

Edward S Ogata ◽

Boyd E Metzger ◽

Norbert Freinkel ◽

C Hunt

Keyword(s):

B Cell ◽

Cell Function ◽

C Peptide ◽

Infants Of Diabetic Mothers ◽

B Cell Function ◽

Cord Plasma ◽

Diabetic Mothers

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Pancreatic beta-cell function and glucose metabolism in human segmental pancreas and kidney transplantation

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1993.264.3.e441 ◽

1993 ◽

Vol 264 (3) ◽

pp. E441-E449 ◽

Cited By ~ 2

Author(s):

E. Christiansen ◽

H. B. Andersen ◽

K. Rasmussen ◽

N. J. Christensen ◽

K. Olgaard ◽

...

Keyword(s):

Insulin Secretion ◽

Glucose Metabolism ◽

Beta Cell ◽

Kidney Transplant ◽

Beta Cell Function ◽

Cell Function ◽

Pancreatic Beta Cell ◽

Secretion Rate ◽

C Peptide ◽

Insulin Secretion Rate

beta-Cell function and glucose metabolism were studied in eight insulin-dependent diabetic recipients of combined segmental pancreas and kidney transplant with peripheral insulin delivery (Px), in eight nondiabetic kidney-transplant individuals (Kx), and in eight normal subjects (Ns) after three consecutive mixed meals. All subjects had normal fasting plasma glucose, but increased basal levels of C-peptide were demonstrated in the transplant groups (P < 0.05 relative to Ns). Postprandial hyperglycemia was increased 14% in Kx and 32% in Px (P < 0.05), whereas compared with Ns postprandial C-peptide levels were increased three- and twofold, respectively, in Kx and Px (P < 0.05). Compared with Ns basal insulin secretion rate (combined model) was increased 2-fold in Kx and 1.4-fold in Px (P < 0.05). Maximal insulin secretion rate was reduced 25% in Px compared with Kx (P < 0.05) but not different from that of Ns (P NS). Also, maximal insulin secretion rate occurred later in Px than in controls (Tmax: Px 50 min, Kx 30 min, and Ns 32 min; P < 0.05). The total integrated insulin secretion was increased 1.4-fold in Px compared with Ns (P < 0.05) but decreased 1.4-fold compared with Kx (P < 0.05). Fasting and postprandial proinsulin-to-C-peptide molar ratios were inappropriately increased in Px compared with Kx and Ns. Basal hepatic glucose production was increased 43% in Px and 33% in Kx compared with Ns (P < 0.05). Postprandial total systemic glucose appearance was similar in all three groups, whereas peripheral glucose disposal was 15% reduced in Px (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

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Pregnancy Enhances the Angiotensin (Ang)-(1–7) Vasodilator Response in Mesenteric Arteries and Increases the Renal Concentration and Urinary Excretion of Ang-(1–7)

Endocrinology ◽

10.1210/en.2003-0009 ◽

2003 ◽

Vol 144 (8) ◽

pp. 3338-3343 ◽

Cited By ~ 35

Author(s):

Liomar A. A. Neves ◽

Aleck F. Williams ◽

David B. Averill ◽

Carlos M. Ferrario ◽

Michael P. Walkup ◽

...

Keyword(s):

Urinary Excretion ◽

Excretion Rate ◽

Virgin Female ◽

Cardiovascular Regulation ◽

Mesenteric Arteries ◽

Female Rats ◽

Resistance Arteries ◽

Urinary Excretion Rate ◽

Response Curves ◽

Mesenteric Vessels

Abstract The vasoactive effect of angiotensin (Ang)-(1–7) in mesenteric resistance arteries together with its plasma and kidney concentration and urinary excretion was assessed in pregnant and virgin rats. Mesenteric arteries (230–290 μm) were mounted in a pressurized myograph system and Ang-(1–7) concentration-dependent response curves (10−10–10−5m) were determined in arteries preconstricted with endothelin-1 (10−7m). The Ang-(1–7) response was investigated in vessels with and without pretreatment with the Ang-(1–7) antagonist [d-[Ala7]-Ang-(1–7)] (10−7m). Ang-(1–7) caused a significantly enhanced, concentration-dependent dilation of mesenteric vessels (EC50 = 2.7 nm) from pregnant compared with virgin female rats. d-[Ala7]-Ang-(1–7) eliminated the vasodilator effect of Ang-(1–7). There was no significant change in plasma concentration of Ang-(1–7) in pregnant animals. On the other hand, 24 h urinary excretion and kidney concentration of Ang-(1–7) were significantly higher in pregnant animals. The increased mesenteric dilation to Ang-(1–7) with enhanced kidney concentration and 24 h urinary excretion rate of Ang-(1–7) suggests an important role for this peptide in cardiovascular regulation during pregnancy.

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Functional significance of exaggerated renal thromboxane A2 synthesis induced by cyclosporin A

AJP Renal Physiology ◽

10.1152/ajprenal.1986.251.4.f581 ◽

1986 ◽

Vol 251 (4) ◽

pp. F581-F587 ◽

Cited By ~ 3

Author(s):

N. Perico ◽

A. Benigni ◽

C. Zoja ◽

F. Delaini ◽

G. Remuzzi

Keyword(s):

Urinary Excretion ◽

Cyclosporin A ◽

Chronic Treatment ◽

Excretion Rate ◽

Thromboxane A2 ◽

Significant Negative Correlation ◽

Progressive Increase ◽

Urinary Excretion Rate ◽

Acid Clearance ◽

Selective Increase

Animals and humans undergoing a chronic treatment with cyclosporin A (CyA) show a reduction in glomerular filtration rate (GFR). The cause of this abnormality has not been established. Since CyA interferes with arachidonic acid (AA) metabolism in various cells, we wished to determine whether alterations in renal AA metabolites contribute to deteriorating renal function in rats on CyA. We show that chronic CyA treatment induces a progressive increase in the renal synthesis of thromboxane (TX) A2. This is a selective abnormality in that CyA does not influence the renal synthesis of prostaglandin E2 (PGE2) and prostacyclin (PGI2). A significant negative correlation has been found between TXB2 urinary excretion rate and inulin clearance. No correlation has been observed between TXB2 excretion and p-aminohippuric acid clearance. The withdrawal of CyA is followed by a normalization of both TXB2 urinary excretion rate and GFR. The administration of a selective TXA2 inhibitor, UK-38,485, resulted in a significant reduction in urinary excretion of TXB2 accompanied by a significant increase in GFR. We conclude that chronic treatment with CyA in rats is associated with a selective increase in renal TXA2 synthesis and suggest that this abnormality may play a role in the reduction of GFR.

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