RESUMEN
Genetic regulation of gene expression is dynamic, as transcription can change during cell differentiation and across cell types. We mapped expression quantitative trait loci (eQTLs) throughout differentiation to elucidate the dynamics of genetic effects on cell type-specific gene expression. We generated time-series RNA sequencing data, capturing 16 time points during the differentiation of induced pluripotent stem cells to cardiomyocytes, in 19 human cell lines. We identified hundreds of dynamic eQTLs that change over time, with enrichment in enhancers of relevant cell types. We also found nonlinear dynamic eQTLs, which affect only intermediate stages of differentiation and cannot be found by using data from mature tissues. These fleeting genetic associations with gene regulation may explain some of the components of complex traits and disease. We highlight one example of a nonlinear eQTL that is associated with body mass index.
Asunto(s)
Diferenciación Celular/genética , Regulación de la Expresión Génica , Miocitos Cardíacos/citología , Línea Celular , Humanos , Células Madre Pluripotentes/citología , Sitios de Carácter Cuantitativo , Análisis de Secuencia de ARNRESUMEN
AIM: Optimal treatment of cardiovascular disease is essential to decrease mortality among people with diabetes, but information is limited on how actual treatment relates to guidelines. We analysed changes in therapeutic approaches to anti-hypertensive and lipid-lowering medications in people with Type 2 diabetes from 2006 and 2015. METHODS: Summary data from clinical services in seven countries outside North America and Western Europe were collected for 39 684 people. Each site summarized individual-level data from outpatient medical records for 2006 and 2015. Data included: demographic information, blood pressure (BP), total cholesterol levels and percentage of people taking statins, anti-hypertensive medication (angiotensin-converting enzyme inhibitors, calcium channel blockers, angiotensin II receptor blockers, thiazide diuretics) and antiplatelet drugs. RESULTS: From 2006 to 2015, mean cholesterol levels decreased in six of eight sites (range: -0.5 to -0.2), whereas the proportion with BP levels > 140/90 mmHg increased in seven of eight sites. Decreases in cholesterol paralleled increases in statin use (range: 3.1 to 47.0 percentage points). Overall, utilization of anti-hypertensive medication did not change. However, there was an increase in the use of angiotensin II receptor blockers and a decrease in angiotensin-converting enzyme inhibitors. The percentage of individuals receiving calcium channel blockers and aspirin remained unchanged. CONCLUSIONS: Our findings indicate that control of cholesterol levels improved and coincided with increased use of statins. The percentage of people with BP > 140/90 mmHg was higher in 2015 than in 2006. Hypertension treatment shifted from using angiotensin-converting enzyme inhibitors to angiotensin II receptor blockers. Despite the potentially greater tolerability of angiotensin II receptor blockers, there was no associated improvement in BP levels.
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Antihipertensivos/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Angiopatías Diabéticas/tratamiento farmacológico , Dislipidemias/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipertensión/tratamiento farmacológico , Anciano , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/fisiopatología , Angiopatías Diabéticas/epidemiología , Angiopatías Diabéticas/fisiopatología , Dislipidemias/epidemiología , Dislipidemias/fisiopatología , Europa (Continente)/epidemiología , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , América del Norte/epidemiologíaRESUMEN
Over a decade after their discovery, induced pluripotent stem cells (iPSCs) have become a major biological model. The iPSC technology allows generation of pluripotent stem cells from somatic cells bearing any genomic background. The challenge ahead of us is to translate human iPSCs (hiPSCs) protocols into clinical treatment. To do so, we need to improve the quality of hiPSCs produced. In this study we report the reprogramming of multiple patient urine-derived cell lines with mRNA reprogramming, which, to date, is one of the fastest and most faithful reprogramming method. We show that mRNA reprogramming efficiently generates hiPSCs from urine-derived cells. Moreover, we were able to generate feeder-free bulk hiPSCs lines that did not display genomic abnormalities. Altogether, this reprogramming method will contribute to accelerating the translation of hiPSCs to therapeutic applications.
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Reprogramación Celular , Orina/citología , Diferenciación Celular , Línea Celular , Pulpa Dental/citología , Fibroblastos/citología , Humanos , Células Madre Pluripotentes Inducidas/citología , ARN Mensajero/genéticaRESUMEN
Objective To determine risk factors for multi-drug-resistant Acinetobacter baumannii (MDR-AB) nosocomial infections in intensive care units in a tertiary care hospital, Makkah, Saudi Arabia. Methods We performed a hospital-based, matched case-control study in patients who were admitted to Al Noor Specialist Hospital between 1 January 2012 and 31 August 2012. The study included cases of A. baumannii nosocomial infection and controls without infection. Controls were matched to cases by age and ward of admission. Results The most frequent site of infection was the respiratory tract (77.3%). Susceptibility to antimicrobial MDR-AB was 92.0% for ceftazidime and ciprofloxacin, while it was 83.3% for imipenem, 83.0% for trimethoprim, 79.0% for amikacin, and 72.7% for gentamicin. Multiple logistic regression of risk factors showed that immunosuppression (OR = 2.9; 95% CI 1.5-5.6; p = 0.002), clinical outcome (OR = 0.4; 95% CI 0.3-0.9; p = 0.01), invasive procedures (OR = 7.9; 95% CI 1.8-34.2; p = 0.002), a central venous catheter (OR = 2.9; 95% CI 1.5-5.6; p = 0.000), and an endotracheal tube (OR = 3.4; 95% CI 1.6-7.3; p = 0.001) were associated with MDR-AB. Conclusions Acinetobacter nosocomial infections are associated with admission to the ICU (Intensive care unit) and exposure to invasive procedures.
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Acinetobacter baumannii/efectos de los fármacos , Infección Hospitalaria/epidemiología , Centros de Atención Terciaria/organización & administración , Acinetobacter baumannii/aislamiento & purificación , Adulto , Anciano , Estudios de Casos y Controles , Infección Hospitalaria/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Arabia Saudita/epidemiologíaRESUMEN
AIMS: To compare the incidence of symptomatic hypoglycaemia in fasting Muslim patients with type 2 diabetes treated with sitagliptin or a sulphonylurea during Ramadan. METHODS: Patients with type 2 diabetes (age ≥ 18 years) who were treated with a stable dose of a sulphonylurea with or without metformin for at least 3 months prior to screening, who had an HbA(1c) < 10% and who expressed their intention to daytime fast during Ramadan were eligible for this open-label study. Patients were randomised in a 1 : 1 ratio to either switch to sitagliptin 100 mg qd or to remain on their prestudy sulphonylurea. Patients completed daily diary cards to document information on hypoglycaemic symptoms and complications. The primary end-point was the overall incidence of symptomatic hypoglycaemia recorded during Ramadan. RESULTS: Of the 1066 patients randomised, 1021 (n = 507 for sitagliptin and n = 514 for sulphonylurea) returned at least one completed diary card and were included in the analysis. The proportion of patients who recorded one or more symptomatic hypoglycaemic events during Ramadan was lower in the sitagliptin group (6.7%) compared with the sulphonylurea group (13.2%). The risk of symptomatic hypoglycaemia was significantly decreased with sitagliptin relative to sulphonylurea treatment (Mantel-Haenszel relative risk ratio [95% CI] = 0.51 [0.34, 0.75]; p < 0.001). There were no reported events that required medical assistance (i.e. visits to physician or emergency room or hospitalisations) or were considered severe (i.e. events that caused loss of consciousness, seizure, coma or physical injury) during Ramadan. CONCLUSIONS: In Muslim patients with type 2 diabetes who observed the fast during Ramadan, switching to a sitagliptin-based regimen decreased the risk of hypoglycaemia compared with remaining on a sulphonylurea-based regimen. The incidence of hypoglycaemia was lower with gliclazide relative to the other sulphonylurea agents and similar to that observed with sitagliptin.
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Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemia/etiología , Hipoglucemiantes/uso terapéutico , Islamismo , Pirazinas/uso terapéutico , Compuestos de Sulfonilurea/uso terapéutico , Triazoles/uso terapéutico , Adulto , Anciano , Diabetes Mellitus Tipo 2/epidemiología , Sustitución de Medicamentos , Ayuno , Femenino , Humanos , Hipoglucemia/epidemiología , Incidencia , Masculino , Persona de Mediana Edad , Medio Oriente/epidemiología , Características de la Residencia , Fosfato de Sitagliptina , Adulto JovenRESUMEN
Our objective was to assess the pattern of type-2 diabetes-associated androgen alteration in patients with erectile dysfunction (ED). A total of 127 diabetic male patients with ED were enrolled in this study. Erectile function was assessed using the International Index of Erectile Function (IIEF). At the time of assessment, patients were also interviewed and assessed for socio-demographic and medical history that includes duration and severity of diabetes mellitus (DM). Patients underwent routine laboratory investigations, in addition to total testosterone (T), dehydroepiandrosterone sulphate (DHEA-S) and insulin assessment. The mean age +/- SD was 53.8 +/- 9.3 years. Of patients 25.2% (n = 32/127), 6.3% (n = 8/127) and 31.5% (n = 40/127) had low total T, low DHEA-S and hyperinsulinaemia respectively. There were significant association between the increase in age and body mass index and the presence of low T level. Of the patients 37.5% (n = 12/32) with low T level had glycosylated haemoglobin (HbA1c) >7% while, 22.1% (n = 21/95) of the patients with normal T level had HbA1c >7% (p < 0.05). There were significant associations between the number of patients with low level of total T or DHEA-S and poor control of DM. Patients with low T level were two times more likely (56.3%, n = 18/32) to have severe ED than patients with normal T level (27.4%, n = 26/95) (p < 0.01). There were significant differences between the mean levels of total T or DHEA-S and poor control of DM. No significant associations were detected between hyperinsulinaemia and the level of fasting blood sugar, duration of DM, metabolic control of DM or ED severity. Patients with low T level were three times as likely to have hyperinsulinaemia as those patients with normal T level (p < 0.05). The current study clearly demonstrated that there were significant associations between low level of total T or DHEA-S and poor control of DM.
Asunto(s)
Sulfato de Deshidroepiandrosterona/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Disfunción Eréctil/fisiopatología , Insulina/sangre , Testosterona/sangre , Envejecimiento , Diabetes Mellitus Tipo 2/complicaciones , Disfunción Eréctil/etiología , Humanos , MasculinoRESUMEN
Primary squamous cell carcinoma of the breast is a rare neoplasma included in metaplastic breast cancer. The histogenesis remains unknown. Clinical and radiological appearances are not specific. Nodal involvement is rare and hormones receptors are negative. The treatment is based on surgery associated to radiation therapy and chemotherapy. Prognosis seems to be similar to others breast carcinoma. We report three cases of primary squamous cell carcinoma of the breast recruited at National Institute of Oncology with review of the literature.
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Neoplasias de la Mama/patología , Carcinoma de Células Escamosas/patología , Adulto , Neoplasias de la Mama/cirugía , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Quimioterapia Adyuvante , Terapia Combinada , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Radioterapia AdyuvanteRESUMEN
When repeated epinephrine infusions are given to normal dogs as a partial stress model, there is exaggerated hyperglycaemia, associated with reduced plasma insulin levels and markedly decreased glucose clearance. In the present study, we have examined the hormonal and metabolic responses to two successive 60-min epinephrine (0.1 microgram . kg-1 . min-1) infusions with or without concomitant infusion of beta endorphin (0.3 microgram . kg-1 . min-1) in 6 alloxan-diabetic dogs. These studies have been compared to similar studies in 5 normal dogs. In the diabetic dogs, plasma glucose rose from 12.3 +/- 2.2 to 16.2 +/- 2.4 mmol/l (p less than 0.001) in response to the first epinephrine infusion and rose further to 18.1 +/- 2.5 mmol/l (p less than 0.001) during the second epinephrine infusion. The increases in plasma glucagon and glucose production were comparable with both infusions, but considerably greater than previously observed in normal dogs. In normal dogs, beta endorphin diminished the insulin response to the first epinephrine infusion (p less than 0.02), and abolished this response to the second (p less than 0.05). In addition beta endorphin also diminished the glucagon response to the second epinephrine infusion (p less than 0.01) and greatly potentiated epinephrine-induced suppression of glucose metabolic clearance during both infusions (p less than 0.001). However, beta endorphin did not appreciably alter the hyperglycaemic response to epinephrine due to a concomitant attenuation of the epinephrine-induced increase in hepatic glucose production. In contrast to normal dogs, beta endorphin did not modulate the effects of either the first or second epinephrine infusion on glucose kinetics in diabetic dogs. Also, beta endorphin failed to inhibit glucagon or insulin secretion in response to epinephrine in the diabetic animals. Since the alloxan-diabetic and normal dogs respond differently to the combined infusion of beta endorphin and epinephrine we conclude that the effects of beta endorphin observed in the normal dogs are dependent upon intact pancreatic endocrine function.
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Glucemia/metabolismo , Diabetes Mellitus Experimental/sangre , Epinefrina/farmacología , betaendorfina/farmacología , Animales , Perros , Relación Dosis-Respuesta a Droga , Epinefrina/sangre , Ácidos Grasos no Esterificados/sangre , Glucagón/sangre , Hidrocortisona/sangre , Infusiones Intravenosas , Insulina/sangreRESUMEN
In order to determine the role of glucagon in futile or substrate cycling in diabetes, we measured tracer determined glucose kinetics during a combined infusion of 2-3H-glucose (total glucose production) and 6-3H-glucose (glucose production) in six alloxan-diabetic dogs. The animals received either a 420 min infusion of (1) somatostatin alone (0.3 microgram X kg-1 X min-1), (2) somatostatin with insulin replacement (100 microU X kg-1 X min-1) or (3) glucagon (6 ng X kg-1 X min-1) together with somatostatin and transient insulin replacement. When somatostatin was given alone, plasma glucagon (p less than 0.004) and insulin (p less than 0.0001) were suppressed. Glucose production and disappearance and plasma glucose concentrations fell (p less than 0.0001), but the metabolic clearance of glucose did not change significantly. In the basal state, futile cycling comprised 29 +/- 4%, 33 +/- 4% and 33 +/- 3% of total glucose production in the three groups of studies, which is high compared to normal dogs. The absolute rate of futile cycling fell slightly but significantly from 10.0 +/- 1.7 to 8.3 +/- 1.7 mumol X kg X -1 min-1 (p less than 0.0008). When insulin replacement was given during somatostatin infusion to correct for the small somatostatin-induced insulin suppression, there were similar changes in plasma glucagon, glucose concentrations and glucose kinetics as seen during the infusion of somatostatin alone. Futile cycling decreased to a slightly greater extent from 12.8 +/- 2.8 to 9.5 +/- 1.7 mumol X kg-1 X min.-1 (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Glucagón/fisiología , Glucosa/metabolismo , Hígado/metabolismo , Animales , Glucemia/metabolismo , Perros , Ácidos Grasos no Esterificados/sangre , Insulina/uso terapéutico , Cinética , Somatostatina/farmacologíaRESUMEN
The importance of basal cortisol (H) and epinephrine (E) levels on glucoregulation, and the effects of E, given to simulate moderate to severe stress (5 times basal rate of infusion), were examined in seven conscious adrenalectomized dogs. Although plasma glucagon (IRG) increased by 47%, insulin (IRI) decreased by 36%, norepinephrine (NE) increased by 103%, and FFA decreased by 26%, glucose concentration and kinetics remained normal after adrenalectomy. A 4-h infusion of H reestablished basal cortisol levels and returned IRG to its basal preadrenalectomy level with no change in IRI, NE, and FFA levels. Glucose production and metabolic clearance decreased concomitantly by 20%, maintaining euglycemia. A 90-min infusion of basal E caused only a transient increase in IRG. The simultaneous infusion of H with E prevented this increase in IRG and returned IRI to preadrenalectomy levels in the absence of any change in NE or glucose. A subsequent infusion of five times basal E, alone, raised circulating E levels and caused a transient decrease in plasma NE, but no change in IRI. There was a similar hyperglycemic response, as seen previously in normal dogs. The simultaneous infusion of H and E prevented the decrease in NE, but did not change the IRI and FFA responses. There was an 80% greater plasma glucose response than seen during infusion of E alone. In conclusion, what E and H lack after adrenalectomy is compensated for by an increase in IRG and a decrease in IRI, and normal glucose concentrations and kinetics are maintained. It appeared that normoglucagonemia required basal H release, whereas normoinsulinemia required both basal H and E secretion.(ABSTRACT TRUNCATED AT 250 WORDS)
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Adrenalectomía , Epinefrina/farmacología , Gluconeogénesis/efectos de los fármacos , Glucólisis/efectos de los fármacos , Hidrocortisona/farmacología , Animales , Glucemia/metabolismo , Perros , Interacciones Farmacológicas , Ácidos Grasos no Esterificados/sangre , Glucagón/sangre , Insulina/sangre , Cinética , Norepinefrina/sangre , Factores de TiempoRESUMEN
The hormonal and metabolic responses of beta-endorphin infused cephalad into the carotid artery, or via the jugular vein, were examined in 10 normal dogs. The intracarotid administration of beta-endorphin resulted in significant increases in plasma glucagon, adrenocorticotropin, and cortisol levels. Hepatic glucose production increased only transiently and there was no significant change in glucose disappearance or plasma glucose concentrations. Infusion of beta-endorphin in the jugular vein gave rise to significant increases in glucagon and cortisol levels and to a transient increase in plasma epinephrine. Although no significant changes in glucose kinetics could be demonstrated, there was a slight transient decrease in plasma glucose concentrations. In conclusion, both intracarotid and intrajugular infusions of beta-endorphin stimulated glucagon secretion independent of circulating catecholamines, and increased cortisol release, probably through activation of the pituitary-adrenocortical axis.
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Endorfinas/farmacología , Hormonas/sangre , Animales , Glucemia/metabolismo , Arterias Carótidas , Perros , Endorfinas/administración & dosificación , Infusiones Intraarteriales , Infusiones Parenterales , Venas Yugulares , Factores de Tiempo , betaendorfinaRESUMEN
By use of the opiate antagonist naloxone, we have examined the hormonal and metabolic responses to opiate-receptor blockade under basal conditions and during insulin-induced hypoglycemia in normal dogs. Naloxone treatment had no measurable effect on glucose concentration, turnover, and norepinephrine levels, but stimulated plasma epinephrine, glucagon, and cortisol and inhibited insulin release. Insulin (7 mU X kg-1 X min-1) decreased plasma glucose to 42 +/- 4 mg/dl due to an initial decrease in glucose production and an increase in glucose disappearance. Glucose production then increased, and plasma glucose plateaued. After 50 min of insulin infusion, epinephrine levels increased 26-fold (P less than 0.05), norepinephrine and glucagon 3-fold (P less than 0.02), and cortisol 4-fold (P less than 0.01). Similarly, plasma beta-endorphin and adrenocorticotropin (ACTH) were elevated (6-fold, P less than 0.01, and 16-fold, P less than 0.05, respectively). When naloxone was given during insulin-induced hypoglycemia, there was earlier release of epinephrine, glucagon, beta-endorphin, ACTH, and cortisol as well as a greater release of glucagon (P less than 0.001) and cortisol (P less than 0.0001). This resulted in a greater increase in glucose production (P less than 0.01), thus lessening the insulin-induced hypoglycemic excursion. In conclusion, in the dog, endogenous opiates may play a small role in the regulation of basal insulin and glucagon release and can inhibit the pituitary-adrenal axis under basal conditions and during hypoglycemia. Thus increased glucose production in response to insulin-induced hypoglycemia is consistent with the excessive response of counterregulatory hormones during opiate-receptor blockade.
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Glucemia/metabolismo , Endorfinas/fisiología , Hipoglucemia/inducido químicamente , Insulina , Naloxona/farmacología , Receptores Opioides/efectos de los fármacos , Hormona Adrenocorticotrópica/metabolismo , Animales , Perros , Endorfinas/metabolismo , Glucagón/metabolismo , Hidrocortisona/metabolismo , Hipoglucemia/metabolismo , Insulina/metabolismo , Norepinefrina/metabolismo , Receptores Opioides/metabolismo , betaendorfinaRESUMEN
Successive epinephrine infusions were used as a partial model to examine hormonal and metabolic responses to repeated stress stimuli. As both the endogenous opiates and epinephrine are released in response to stress, we have also studied interactions between epinephrine and B-endorphin. Epinephrine (0.1 microgram/kg . min) was infused for 60 min, followed by a 60-min recovery, in nine normal, conscious dogs. In a similar study, B-endorphin (0.06 microgram/kg . min) was given 30 min before epinephrine, then continuously infused throughout the study (N = 4 dogs). When epinephrine was infused, levels rose to 600-800 pg/ml. The changes in glucagon, B-endorphin, FFA, and hepatic glucose production were similar during both epinephrine infusions, but there was a diminished insulin response, a greater decrease in glucose metabolic clearance, and a greater increase in plasma glucose with the second epinephrine infusion. When B-endorphin was given, plasma levels increased to 5.3 ng/ml. Compared with the infusion of epinephrine alone, there was a much greater rise in plasma glucose due to greater suppression of glucose metabolic clearance. With the second epinephrine infusion, however, the changes in glucose concentration were not substantially different from those seen during the second infusion of epinephrine alone, as both hepatic glucose production and glucose metabolic clearance were suppressed. B-endorphin diminished the insulin and glucagon responses during the first epinephrine infusion and abolished them during the second, but did not alter the FFA, ACTH, or cortisol responses to epinephrine.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Endorfinas/farmacología , Epinefrina/farmacología , Glucosa/metabolismo , Hormona Adrenocorticotrópica/sangre , Animales , Glucemia/metabolismo , Glucemia/fisiología , Diabetes Mellitus Tipo 2/metabolismo , Perros , Epinefrina/sangre , Ácidos Grasos no Esterificados/sangre , Glucosa/fisiología , Humanos , Hidrocortisona/sangre , Insulina/sangre , Islotes Pancreáticos/efectos de los fármacos , Conejos , betaendorfinaRESUMEN
We have investigated catecholamine-glucagon-insulin interactions using three stress models: 1) hypoglycemia; 2) exercise; and 3) epinephrine infusion. Phlorizin caused mild hypoglycemia with hypoinsulinemia. Plasma glucagon increased as did hepatic glucose production. Catecholamines did not increase. Insulin caused severe hypoglycemia. Metabolic counterregulation was due mainly to the 40-fold increase in epinephrine. Glucagon played a role only in the recovery from insulin-induced hypoglycemia, which could reflect increased hepatic sensitivity to glucagon with declining plasma insulin. Glucagon suppression during exercise caused transient hypoglycemia due to an inadequate rise in glucose production. Exaggerated epinephrine release during hypoglycemic exercise prevented severe hypoglycemia by inhibiting glucose utilization and stimulating glucose production, with an associated increase in lactate and free fatty acid levels. Hypoglycemic exercise also caused increased cortisol release. Counterregulation was prevented by a euglycemic clamp. We conclude that, during exercise, glucagon is directly responsible for 80% of the increment of glucose production and controls glucose uptake by the muscle indirectly; thus glucagon spares muscle glycogen by increasing hepatic glucose production. Epinephrine infusion in normal dogs caused a transient increase in glucose production and a sustained inhibition of glucose clearance, resulting in hyperglycemia. Insulin rose transiently, followed by a relative inhibition of secretion. Glucagon suppression did not modify the metabolic effects of epinephrine. In alloxan-diabetic dogs, the glucagon response to epinephrine was augmented, whereas in depancreatized dogs, during subbasal insulin infusion, the hepatic response to glucagon was excessive. Glucagon suppression diminished hepatic responsiveness to epinephrine in both models. Stress-induced diabetic instability could relate to exaggerated glucagon release or to increased hepatic sensitivity to glucagon. Thus, during hypoglycemia, exercise, or epinephrine infusion, prevailing plasma insulin levels govern the relative metabolic roles of epinephrine and glucagon.