Glycemic Curve Research Articles

Perreyia flavipes larvae toxicity

Fresh or thawed Perreyia flavipes larvae were ground and mixed with water and orally ad ministered to sheep. At 5mg/kg, neither clinical nor enzymatic changes were observed. Unique do ses of 7.5 and 10mg/kg induced characteristic clinical signs of Perreyia sp. larvae poisoning, increased GGT and AST values, and decreased glycemic curves. However, doses of 5, 10, and 15mg/kg repeated at 30 or 15 days intervals caused no disease and mild disease followed by death, respectively. These fin dings indicate that these animals probably developed some degree of tolerance to the toxins in P. flavipes larvae. Ultrastru ctural examination of liver revealed proliferation of the smooth endoplasmic reticulum in the hepatocytes, which may be associated with an increased ability to metabolize toxins and could consequently lead to the tolerance observed in the present study. Further investigations may elucidate whether such tolerance effects could be applied as a control measure for P. flavipes poioning or other hepatotoxic diseases. In addition, clinicopathological findings were discussed.

Famotidine inhibits glycogen synthase kinase-3β: An investigation by docking simulation and experimental validation

Famotidine was investigated as an inhibitor of glycogen synthase kinase-3β (GSK-3β) in an attempt to explain the molecular mechanism of its hypoglycemic side effects. The investigation included simulated docking experiments, in vitro enzyme inhibition assay, glycogen sparing studies using animal models and single dose oral glucose tolerance test (OGTT). Docking studies showed how famotidine is optimally fit within the binding pocket of GSK-3β via numerous attractive interactions with some specific amino acids. Experimentally, famotidine could inhibit GSK-3β (IC50 = 1.44 μM) and increased significantly liver glycogen spares in fasting animal models. Moreover, a single oral dose of famotidine was shown to decrease the glycemic response curve after 75 g OGTT

Metabolic and cardiovascular effects of AT1 receptor blockade in rats with diet‐induced obesity

Causes of metabolic and cardiovascular disturbances in obesity are poorly understood. This study analyzed whether the angiotensin II receptor blockade reverses abnormalities in diet‐induced obesity. Wistar‐Kyoto rats (n=40) were subjected to control (C) or hypercaloric diet (OB) for 30 weeks and then assigned to four groups: C, C+Los, OB, and OB+Los. Los‐groups received losartan (30mg/kg/day) during five weeks. Subsequently, cardiac structures and function were assessed by echocardiography. Glycemia was studied by tolerance glycemic curve. OB‐groups presented higher body mass and adiposity. Other results are in the table.ConclusionLosartan improves metabolic and cardiovascular profile in diet‐induced obesity.

Phase IV Study Comparing Diurnal Glycemic Profile Following the Administration of 2 NPH Plus Regular Human DNA Recombinant Insulin Regimens in Type 1 Diabetes Mellitus (T1DM) Adult Patients

Intensive insulin therapy (IIT) based on multiple daily injections of long plus rapid-acting insulin has been demonstrated to reduce mortality and morbidity associated with chronic hyperglycemia in T1DM patients. The objective of this study was to assess and compare the postprandial glycemic profile over a diurnal 12 h-period produced by the administration of a new NPH plus regular human DNA recombinant IIT (test regimen) relative to the reference IIT in T1DM patients. A phase IV, single-center, open-label, randomized, multiple-dose, balanced, cross-over study in 12 T1DM patients was conducted. Patients were assigned to receive either the test (Densulin® N (NPH) plus Densulin® R (regular),100 UI/ml, Denver Farma, Argentina) followed by the reference (InsulatardHM® (NPH) plus ActrapidHM®,100 UI/ml, Novo Nordisk Pharma Argentina) regimens or viceversa, according to a random sequence. Each treatment regimen consisted of 2 phases of an ambulatory run-in period of 7 days followed by 12 h confinement period. Blood glucose levels were measured. Glycemic profile was evaluated through glycemic plasma-concentration time curves, area under the time-concentration glycemic curves from basal to 2 h (GlyAUC0-2) and to 12 h (GlyAUC0-12) postprandial, and maximum glycemic postprandial concentration (GlyCmax). 12 hour glycemic concentration-time curves were similar for both test and reference regimens. Geometric least square means ratios Test/ref regimens and their 90% confidence interval for GlyAUC0-2, GlyAUC0-12 and GlyCmax were 94.33 (81.13-125.09), 107.75 (94.05-123.45) and 105 (92.89-118.68), respectively. Both regimens presented similar safety profile. This study demonstrated that the new human DNA recombinant NPH and regular insulin is equally effective to the reference regimen for postprandial diurnal glycemic profile.

Chromium(III) in cactus pad and its possible role in the antihyperglycemic activity

The antihyperglycemic activity of cactus pads and pulp fruit of species of Opuntia genus has been documented; however, the mechanism of action has not yet been clarified. Thus, cactus pad and pulp fruit extracts of Opuntia dillenii were used to evaluate their effects on blood glucose concentration and glycemic curve of Sprague–Dawley rats. After acute administration, no significant differences were observed in the glycemic curve among cactus pad, pulp fruit and control groups. However, the glycemic peaks and glycemic curves obtained in the groups corresponding to both cactus pad and pulp fruit as well as the Cr(III) group were less pronounced than in the control group after 8days of daily intake. Besides, a slight decrease of fasting blood glucose was observed, maintaining within the normal levels, after 8days of daily intake of cactus pad extract. Therefore, the possible role of Cr(III) present in high amounts in these vegetable foods was suggested, for the first time, to explain their antihyperglycemic activity.

Вплив агматину на показники системи крові щурів за умов експериментального цукрового діабету

The effects of agmatine – product of L-arginine decarboxylation – on glucose utilization (on indicators of glucose tolerance test), glycosylated hemoglobin level, indices of the erythron system, counts of platelets, leukocytes and differential white blood cell count of rats’ peripheral blood under the condition of experimental diabetes mellitus (EDM) were investigated. Conducting the oral glucose tolerance test it was determined that agmatine treatment at 1st day experiment and within 14 days leads to slower dynamics and degree of glucose absorption in control animals. Glycemic curve in diabetic animals under treatment with agmatine within 14 days was similar to control, which may be due to slow intake of sugars in the gastrointestinal tract and uniform loading on the insular apparatus throughout the digestion process The treatment with agmatine of control animals did not cause statistically significant changes in the indices of the blood system, but led to decrease in the glucose concentration to physiological values and normalization of the percentage of segmented neutrophils, monocytes and peripheral blood lymphocytes in diabetic group. Such changes reflect the positive effect of agmatine on hematological parameters and functioning of the immune defense of the organism in EDM. Keywords: agmatine, experimental diabetes mellitus, glucose tolerance test, blood cells.

The progression from obesity to type 2 diabetes in Alström syndrome

Alström syndrome (ALMS) is a rare autosomal recessive monogenic disease associated with obesity, hyperinsulinemia, and alterations of glucose metabolism that often lead to the development of type 2 diabetes at a young age. To study the relationship between weight and metabolism in a group of ALMS patients and matched controls. Fifteen ALMS patients (eight males, seven females; aged 3-51) were compared in a cross-sectional study with an age- and weight-matched control population. Anthropometric parameters, fat mass, glucose and insulin secretion in basal and dynamic oral glucose tolerance test (OGTT) conditions were measured. Furthermore, anthropometric and body composition data were obtained from an international group of 27 ALMS patients (13 males, 14 females, age range: 4-29 yr). In ALMS we observed an inverse correlation between age and standard deviation scores for height, weight, and body mass index. The OGTT glycemic curves of ALMS subjects were similar to those of age-matched controls, whereas insulin response was clearly greater. In ALMS individuals the insulin response showed a reduction with age. We documented pathologic values of the derived indices homeostasis model assessment of insulin resistance (HOMA-IR), insulin sensitivity index, HOMA%β-cell and insulinogenic index in ALMS, but unlike the insulin-resistance indices, the β-cell function indices showed a significant reduction with age. In ALMS the progression from the early onset obesity toward the impaired fasting glucose or impaired glucose tolerance and overt diabetes is mostly because of a progressive failure of β-cell insulin secretion without any further worsening of insulin resistance with age, even in the presence of weight reduction.

Cortisol, resposta glicêmica e secreção de insulina em equinos clinicamente sadios submetidos a sessões de hipóxia normobárica

Os níveis séricos de cortisol, resposta glicêmica e secreção de insulina foram avaliados em equinos não exercitados submetidos a sessões de hipóxia normobárica. Cavalos adultos sadios (n=8) foram selecionados após exame físico e submetidos ao teste de tolerância à glicose intravenosa (0,5g kg-1) (TTGIV). Amostras de sangue (n=11) foram coletadas entre 0 e 180 minutos após a administração de glicose para avaliar a resposta glicêmica e a secreção de insulina. Os animais foram então expostos a sessões de uma hora de hipóxia duas vezes ao dia, totalizando 43 sessões, com concentração decrescente de O2 de 17 a 12%. A frequência cardíaca e as amostras sanguíneas para a determinação do cortisol sérico foram coletadas antes e a cada 15 minutos durante as sessões 1, 4, 6, 8, 10, 14, 22 e 43. A TTGIV foi repetida ao final do estudo. Os níveis de cortisol sérico foram maiores na sessão 1 (S1) (17% O2) quando comparados aos níveis da S10 (13% O2) e da S43 (12% O2)(P<0,05). A curva glicêmica de equinos clinicamente sadios não submetidos a exercício não é alterada pela exposição a 43 sessões de hipóxia normobárica. O aumento na secreção de insulina, acompanhada de diminuição da frequência cardíaca e cortisol sérico sugerem uma adaptação dos cavalos ao modelo de hipóxia utilizado.

Different Circulating Ghrelin Responses to Isoglucidic Snack Food in Healthy Individuals

The last decade has seen much debate on ghrelin as a potential target for treating obesity. Despite a close connection between snack food intake and obesity, snacking is controversially reviewed as a good habit in a healthy nutritional regimen. The aim of the study was to evaluate whether a different nutrient composition influences postprandial ghrelin levels and glucose increments induced by 6 isoglucidic snack food. 20 healthy individuals (10 M/10 F; BMI 23.1 ± 0.5; age 33 ± 0.67 years, mean and SE) from H San Raffaele Scientific Institute and Milan University were enrolled. The subjects underwent OGTT (50 g) and 6 isoglucidic test-meal loads to assess the ghrelin circulating levels and the area under glycemic curves induced by 6 commercial snacks. 3 h after hazelnut chocolate intake, ghrelin was significantly lower than with wafer chocolate intake (p<0.002). As a response to all snacks, the glycemic curves were not different even though hazelnut chocolate showed the lowest glycemic curve. Moreover, snack fat content was found to be inversely correlated to 3-h plasma ghrelin levels (p<0.0001; R (2)=0.77) and positively associated with satiety scores (p<0.02; R (2)=0.28). Also energy load was inversely correlated to 3-h plasma ghrelin (p<0.0001; R (2)=0.73). Our results indicate that snack food administered in equivalent glucidic loads elicits postprandial ghrelin suppression and satiety ratings in different ways. Further studies are needed to elucidate the role of ghrelin as hunger-hormone in the regulation of energy balance.

In Vitro Colonic Fermentation and Glycemic Response of Different Kinds of Unripe Banana Flour

This work aimed to study the in vitro colonic fermentation profile of unavailable carbohydrates of two different kinds of unripe banana flour and to evaluate their postprandial glycemic responses. The unripe banana mass (UBM), obtained from the cooked pulp of unripe bananas (Musa acuminata, Nanicão variety), and the unripe banana starch (UBS), obtained from isolated starch of unripe banana, plantain type (Musa paradisiaca) in natura, were studied. The fermentability of the flours was evaluated by different parameters, using rat inoculum, as well as the glycemic response produced after the ingestion by healthy volunteers. The flours presented high concentration of unavailable carbohydrates, which varied in the content of resistant starch, dietary fiber and indigestible fraction (IF). The in vitro colonic fermentation of the flours was high, 98% for the UBS and 75% for the UBM when expressed by the total amount of SCFA such as acetate, butyrate and propionate in relation to lactulose. The increase in the area under the glycemic curve after ingestion of the flours was 90% lower for the UBS and 40% lower for the UBM than the increase produced after bread intake. These characteristics highlight the potential of UBM and UBS as functional ingredients. However, in vivo studies are necessary in order to evaluate the possible benefit effects of the fermentation on intestinal health.

Insulin resistance index (HOMA-IR) in the differentiation of patients with non-alcoholic fatty liver disease and healthy individuals

Due to its good correlation to glycemic clamp, HOMA-IR has been widely utilized as insulin resistance index in clinical and epidemiological studies involving non-alcoholic fatty liver disease carriers. However, values used for this parameter have shown large variability. To identify the HOMA-IR cut value that best distinguishes non-diabetic non-alcoholic fatty liver disease patients from a control group. One hundred sixteen non-alcoholic fatty liver disease patients were studied, diagnosed by clinical, biochemical, and liver image or biopsy criteria, and 88 healthy individuals, without any liver disease and testing for oral glucose tolerance within normality. These groups did not differ in age and gender. All were submitted to oral glucose tolerance test and blood samples were collected for glucose and insulin measurements by immunofluorometric method. HOMA-IR was calculated according to the formula: fasting insulin (microU/L) x fasting glucose (nmol/L)/22.5. NAFLD patients showed higher insulin, glycemia, and HOMA-IR values than control group, even when excluding glucose intolerant and diabetes mellitus patients by their glycemic curves. HOMA-IR 75th percentile for control group was 1.78 and the best area under the curve index was obtained for HOMA-IR values of 2.0 [AUC= 0.840 (0.781-0.899 CI 95%), sensitivity (Se): 85%, specificity (Sp): 83%] while value 2.5 showed best specificity without important loss in sensitivity [AUC=0,831 (0.773-0.888) Se = 72%, Sp = 94%]. HOMA-IR values above or equal to 2.0 or 2.5 show enhanced diagnostic value in distinguishing non-alcoholic fatty liver disease carriers from control group individuals.

Ultrasound Lipoclasia on Subcutaneous Adipose Tissue to Produce Acute Hyperglycemia and Enhance Acute Inflammatory Response in Healthy Female Rats

Ultrasound lipoclasia (USL) on white adipose tissue (WAT) has been largely used in the treatment of cellulite. Nevertheless, the acute consequences of this therapy on metabolism and biochemical profile are significant and should be taken into account. To analyze the acute metabolic effects of USL in WAT of healthy rats using analyses of body composition, biochemical profile, and inflammatory markers. Female Wistar rats weighing approximately 250 g were divided into two groups (n=10 each): control and treated. The treated group was submitted to USL, a single 3-MHz ultrasound application (5.6 W/cm(2)), in gluteal-femoral WAT (3 cm(2)) for 3 minutes. Animals were subjected to glycemic control. Body composition was analyzed using bio-impedance, and lipid profile, insulinemia, C-reactive protein (CRP), and lactate dehydrogenase (LDH) were measured. USL reduced (p<.05) body fat mass. The basal metabolic rate was found to have increased (p<.05). Basal insulin and the lipoprotein profile were not different, although the glycemic curve and CRP and LDH (p<.05) levels were higher. Fat mobilization using USL provokes acute hyperglycemia and enhances an acute inflammatory response, producing cardiometabolic risk in female rats.

Study of new capacities in the evaluation of glycemic control in patients with type 2 diabetes

The purpose of the study was to comprehensively analyze glycemic control in type 2 diabetes (T2D) patients who were first given glucose-reducing therapy. Glidiab MB and Diabeton MB caused a comparable reduction in glycemic control parameters: the level of HbA1c, fasting glycemia, and mean glycemic levels as shown by the results of its continuous glucose monitoring system (CGMS) study. The lower glycemic level was not accompanied by weight gain and it improved lipid spectrum parameters. The readings of monthly self-control of glycemia were transformed to its deviation from the goal range (ADRR) that and the hyper- and hypoglycemia indices calculated from the continuous glycemic control were used to evaluate glycemic lability not reflected by HbA1c. In this connection ADRR may be used to evaluate the efficiency of sugar-reducing therapy and in the examined groups it proved to be low, which generally reflects the stable course of the disease in new cases of T2D. The mean glycemic value calculated from CGMS data virtually coincides with the mean glycemia estimated from glycemic self-control readings both on the day of continuous glucose monitoring and in the month to come before and after CGMS study. In this connection the latter is justified only when the continuous glycemic curve undergoes a complex analysis. The complex analysis of the continuous glycemic curve includes symmetrization of the continuous glycemia scale; calculation of hyper- and hypoglycemic indices, hourly diurnal hyperglycemic index and hourly glycemic variations (Poincare method). The use of this procedure could compare the glucose-reducing effect of the two drugs within the framework of a short-term study.

Analysis of a continuous 24-hour glycemic curve by the symmetrization method

The study included 18 patients (10 females and 8 males) with a not less than 2 year-history of type 1 diabetes (T1D), who had received insulin therapy since its diagnosis was established. The patients ' mean age was 32.9± 13.0 years; the mean duration of TID was 15.1+11.5 years; the mean daily dose of insulin was 40.1+16.0 units; the mean level of glycosylated hemoglobin (HbAJ was 9.4±2.1% (the normal value 4.4-4.9%). The glycemic curve symmetrization method proposed for statistical analysis of glycemic self-control is also quite suitable for the statistical monitoring of a continuous daily glycemic curve. The high and low glycemic indices calculated from the symmetrized glycemic data correlate well with the level of HbAk and with the duration of hypoglycemia and hyperglycemia and hence they may be used as additional criteria for a risk of diabetes complications. The criteria, calculated from the symmetrized data of glycemia for the risk of hyper- and hypoglycemia, adequately reflect the behavior of a continuous glycemic curve and may be used as integral indices of the efficiency of glucose-reducing therapy in clinical practice.

Antihyperglycaemic effect of Coreopsis tinctoria aqueous extract in streptozotocin-induced glucose-intolerant rats

Coreopsis tinctoria Nutt. has been traditionally used in Portugal for the treatment of diabetes [1]. In a previous study we showed that marein was the main chalcone of the infusion and that a single administration of this extract has no effect on oral glucose tolerance in normal Wistar rats [2]. We now report the effect of C. tinctoria infusion on glucose intolerant Wistar rats. Glucose intolerance was induced by a single intraperitoneal injection of streptozotocin in saline solution (40mg/Kg b.w.). After one week, an Oral Glucose Tolerance Test (OGTT) was preformed and rats were considered intolerant when the fasted blood glucose was similar to normal rats (65±10,8mg/dl) but the AUC of glycemic curves (0 to 180min) were higher than those of normal rats (AUC=20048±1752 vs. AUC=25646±2499; p 0.05 but vs. AUC (Control 2)=26248±1081, p<0.01). Conclusion: C. tinctoria aqueous extract is able to revert the streptozotocin-induced glucose-intolerance in rats after 3 weeks of treatment, possibly through an induction of β-pancreatic regeneration, but this hypothesis and the mechanism are under investigation. Acknowledgements: Science and Technology Foundation, for the PhD grant

The glycemic index of bread and biscuits is markedly reduced by the addition of a proprietary fiber mixture to the ingredients

Background and aim Low glycemic index (GI) foods are associated with improved prevention and control of metabolic and cardiovascular diseases (e.g. diabetes and myocardial infarction), even if the impact of their consumption within mixed meals is difficult to predict. Since the availability of wheat based products maintaining taste and texture of traditional ones, but with a low GI, is of relevant nutritional interest, the aim of this study was to assess the effects of a specific proprietary fiber mix, added to the wheat flour used for biscuits and bread preparation, on their GI. Methods and results Fifteen healthy non-diabetic volunteers ate on different days a portion equivalent to 75 g of available carbohydrates, of fiber enriched bread, traditional bread, fiber enriched biscuits and traditional biscuits, or a solution of 75 g of glucose in water. The glycemic index of each product was calculated by relating the area under their glycemic curve to that of glucose. The areas under the glycemic curves of fiber enriched bread and biscuits were lower than those obtained with the equivalent control food. Consequently, a marked reduction of their GI of 21% and 41% for bread and biscuits, respectively, was observed. Conclusion The fiber mix added to the flour used in the preparation of biscuits and bread markedly reduces their GI. A similar effect could be expected in other oven-baked foods produced using the same fiber supplementation.

Correlation Level of HbA1с and postprandial glycemia in type 2 diabetes in the oral glucose tolerance test

A number of today's analytical methods for postprandial glycemia in the oral glucose tolerance test (OGTT) still remain to be substantiated. The standard OGTT using 75 g of glucose was performed in 42 type 2 diabetes mellitus (DM-2) patients who received diet therapy. The concentration of Hb A1c has been found to correlate with absolute levels of glycemia during 1- and 2-hour OGTT. However, exclusion of fasting glycemia from the level of glycemia at 1 and 2 hours of OGTT leads to cession of the correlation of HbA1c with these values of the test. Only 7 out of the 8 today's parameters for calculating the areas under the glycemic curve in OGTT correlate with the level of HbA1c. Moreover, 5 out of these 7 parameters are equivalent (r - 1; p < 0.05). The recently proposed two new parameters for calculating the areas under the glycemic curve in OGTT, one of which is constant 6.1, have proved to be equivalent (r= 1; p < 0 05) and to be actually reduced to one. The correlation with Hb Ah holds if any other constants from 5 to 11 mmоl/l are inserted instead of the constant 6.1 for calculating the area, the highest coefficient correlation with Hb A1c is achieved at the constant equal to 6.1. The correlation usually detectable at DM-2 between the concentration of Hb A,c and the absolute level of postprandial glycemia (glycemic spike in particular) Is mainly determined by its implicit inclusion of fasting glycemia. A set of 4 nonequivalent OGTT parameters should be used when the relationship of diabetes mellitus complications to the OGTT parameters that correlate with HbA,cis studied. The constants 5.6 and 6.1 reflect different aspects of the development of complications in diabetes mellitus when they are included in the calculation of an area in OGTT.

Comparison of glycemic index of spelt and wheat bread in human volunteers

The assessment of the glycemic index (GI) seems to be an important parameter to take into account in order to better understand the physiologic effects of foods with high carbohydrate levels. Among cereals, which are major sources of carbohydrates, spelt ( Triticum spelta L.) has been considered as particularly interesting from a nutritional point of view. The aim of this study was to evaluate in vivo the GI of white spelt bread in healthy subjects. The wheat ( Triticum aestivum L.) white bread was used as reference food. To avoid differences in the production of both breads, spelt and wheat breads were baked under the same controlled conditions. Results showed that the glycemic profile of spelt white bread was not different from that of wheat white bread (GI of 93 ± 9). The area under the glycemic curve significantly and negatively correlated to fasting glycemia and carbohydrate intake during evening meals preceding the test. In conclusion, the glycemic response to spelt bread was similar to that of wheat bread. However, in order to avoid more inter-individual variability, our data supports the importance to propose standardised carbohydrate content for the last meal before evaluating the GI of food.

Comparison of Apolipoprotein B100 Metabolism between Continuous Subcutaneous and Intraperitoneal Insulin Therapy in Type 1 Diabetes

In type 1 diabetic patients, the replacement of s.c. insulin infusion with i.p. insulin infusion restores the normal physiological gradient between the portal vein and the peripheral circulation, which is likely to modify lipoprotein metabolism. To check this hypothesis, we performed two apolipoprotein (apo) B100 kinetic studies in seven type 1 diabetic patients, first under s.c. insulin infusion and then 3 months after the beginning of i.p. insulin infusion. Glycemic control was similar under s.c. insulin infusion and i.p. insulin infusion, as assessed by glycated hemoglobin A1c and the capillary glycemic curve determined during the kinetic study. Very low-density and intermediate-density lipoprotein apoB100 pool size, production rate, and fractional catabolic rate (FCR) were similar under s.c. insulin infusion and i.p. insulin infusion. The low-density lipoprotein apoB100 FCR tended to decrease under ip insulin (0.45 +/- 0.06 vs. 0.55 +/- 0.11 pool/d), but the difference did not reach statistical significance (95% confidence interval for the difference, -0.33, 0.11). The low-density lipoprotein apoB100 pool size and production rate remained unchanged under i.p. insulin infusion compared with s.c. insulin infusion. In type 1 diabetic patients, the replacement of s.c. insulin infusion with i.p. insulin infusion does not induce profound modifications of apoB100-containing lipoprotein production and FCRs.

Use of different anticoagulants for HPLC separation and quantification of the free amino acid content of plasma

AbstractAmino acid analysis in plasma samples is a very important and difficult task and could represent a useful tool for preventing the occurrence of some diseases (diabetes, cancer, HIV disease). Even though amino acid analysis has been thoroughly investigated, there are still some steps which are not so clear in this analytical procedure, e.g. the coagulation process of the blood to afford plasma and serum. Various anticoagulants are used in clinical chemistry: in this paper we have investigated three commonly used anticoagulants, heparin, EDTA, and sodium citrate. The blood samples have been divided into three portions and each portion treated with a different anticoagulant. The entire analytical procedure (from blood collection to the coagulation all the way to HPLC analysis) has been extensively investigated; the chromatograms and the amino acid recoveries are reported, and the three anticoagulants compared. Finally, the best anticoagulant has been used to analyze glycemic curves of healthy patients: the behavior of essential amino acids in the different blood samples withdrawn has been studied.