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1.
Ten healthy male volunteers were studied to compare the effectiveness of intravenous and subcutaneous injections of 1 mg of glucagon on HG secretion. Plasma HGH level rose to a peak of 6 ng/ml or greater 120 minutes after the subcutaneous injection of glucagon (sc glucagon) in all subjects, whereas the intravenous injection of glucagon (iv glucagon) caused comparable increments in plasma HGH in only six out of ten subjects. Furthermore, in comparison to those in sc glucagon the periods required to show maximum responses were less consistent in iv glucagon. Plasma IRG levels reached a peak of 102.4+/-22.6 ng/ml at two minutes following iv glucagon, and a peak of 3.33+/-1.08 ng/ml at 15 minutes following sc glucagon. These fell to initial levels at 60 minutes and at 180 minutes, respectively. There was no definite correlation either between the magnitudes of changes in plasma IRG and HGH levels or between the velocities of decrement in blood sugar and HGH responsiveness. Judging from its simplicity and reproducibility it may be concluded that sc glucagon is more suitable for a clinical provocative test of HGH release than is iv glucagon. In regards to the mechanism of glucagon-induced HGH release, neither glucagon per se nor the fall of blood sugar after hyperglycemia was assumed to play any major role. The sustained elevation of plasma IRG for a certain period might be responsible for the glucagon-induced HGH release.  相似文献   

2.
Although poisoning with calcium channel blocking agents is frequent, to our knowledge no cases involving amlodipine have been published. We describe here a case of amlodipine intoxication, in which protracted hypotension did not respond to vasopressor therapy alone. After the addition of continuous calcium chloride and glucagon infusion, blood pressure was restored and vasopressor therapy could be tapered off substantially. When calcium and glucagon were interrupted because of severe hypercalcemia and hyperglycemia, the patient developed irreversible hypotension and died. Either glucagon or calcium or both, and to some extent vasopressors, seem to have constituted effective treatment of hypotension in this case.  相似文献   

3.
Drug loads were used to diagnose impairments of the hypothalamic-pituitary-adrenal system in 209 patients with bronchial asthma. A thyroid-releasing hormone test made in patients with moderate bronchial asthma who were taking no corticosteroids (CS) demonstrated a high level of thyroid-stimulating hormone at min 60 of the agent administration, which was indicative of decreased hypothalamic function. In 67.8% of patients, the vasopressin test was positive and suggested that the pituitary preserved its functional capacities. The decreased secretion of hydrocortisone and its active forms was observed in patients with severe bronchial asthma when CS was used in the daily dose adequate to 10-15 mg of prednisolone for 5 years. The 20-day therapy with dexamethasone demonstrated that the agent reduced the synthesis of hydrocortisone to a greater extent than that of corticosterone. The administration of depot-synacthen 24 hours later elevated the content of all hydrocortisone fractions and biologically active corticosterone. Depot-synacthen exerted an active stimulating action on the adrenal cortex.  相似文献   

4.
The present study examines the role of insulin, glucagon and cortisol in the regulation of gluconeogenesis from lactate and amino acids in fetal and newborn rats. Injection of glucagon in the full-term fetal rat caused a rise in glucose (and insulin) and a fall in blood levels of most individual amino acids, stimulated hepatic accumulation of 14C-amino isobutyric acid and 14C-cycloleucine and increased the conversion of 14C lactate, alanine and serine to glucose in vivo and in vitro (liver slices). Such changes were equivalent to the changes seen in 4 h old newborn rats. When glucagon was administered at birth, little difference was observed between control and treated animals in plasma amino acids and a smaller increment in conversion of 14C substrate to glucose occurred. By contrast, insulin injection at birth caused hypoglycemia, suppression of levels of certain amino acids and inhibition of conversion of 14C substrates into glucose. Glucose injection at birth caused elevated glycemia and plasma insulin and suppression of most amino acid levels and of conversion of 14C substrate into glucose. Cortisol injection at birth caused a marked, generalized by hyperaminoacidemia, a stimulation of glucagon secretion and of conversion of 14C substrates into glucose. These observations support the thesis that glucagon plays a major role in the induction of hepatic gluconeogenesis and that insulin acts as an antagonist hormone.  相似文献   

5.
The lysosomal glycosidase activity of the eye tissues (the sclera and cornea), the bone tissues and cartilage were studied. The intraperitoneal injection of tyrocalcitonine (TCT), deoxycorticosterone (DOCS), hydrocortisone (HC), and somatotropic hormone (STH) influenced both the activity of beta-galactosidase, beta-glucosidase, and hyaluronidase, the the functional state of thy lysosomal membranes of the connective tissues under investigation. GC and STH caused stabilization, whereas DOCS and large doses of TCT--a labilizing effect on the lysosomal membranes and tissues understudy. The absolute activity of the enzymes in the homogenates decreased after the HC and STH injection. DOCS produced an opposite effect.  相似文献   

6.
Seventeen diabetic patients (5 males and 12 females) treated with long-term metformin therapy received their morning dose after an overnight fast or after one of four types of breakfast: low protein, low fat, low carbohydrate or standard. Mean (+/- SD) and median areas under the serum concentration curves (AUC), maximum concentrations (Cmax) and time to reach the maximum concentrations (tmax) were calculated for the major biological parameters (glycemia, C-peptide, insulin and glucagon levels). None of the diets were bioequivalent to the fasting condition and only the low carbohydrate diet gave comparable results. A strong relationship was found between the carbohydrate intake (in g) and the AUC of the various markers except glucagon.  相似文献   

7.
8.
Estrogen replacement therapy (ERT) is known to prevent bone loss following the menopause, but the mechanism for this is unclear. Estrogen may suppress the secretion of certain bone-resorbing cytokines. The aim of this study was to assess the effect of ERT on the levels of cytokines measured in peripheral blood. We measured cytokines in 10 postmenopausal women (ages 56-59, 3-9 years since menopause) treated with ERT and 10 age-matched (54-59 years, 4-10 years since menopause) untreated women as controls. Samples of blood were taken and used for mononuclear cell cultures, whole blood (WB) cultures, and the separation of serum. The cultures were treated with lipopolysaccharide (LPS; 500 ng/ml) and hydrocortisone (10(-6) M). The conditioned medium from cultures and the serum were then assayed for interleukin-6 (IL-6), IL-1alpha IL-1beta, IL-1 IL-1ra, tumor necrosis factor alpha (TNF-alpha), and granulocyte macrophage colony stimulating factor (GM-CSF) by enzyme-linked immunosorbent assay. M-CSF and the soluble cytokine receptors soluble IL-6 receptor (sIL-6r) and soluble TNF receptor type 1 (sTNFr1) were also measured in serum and M-CSF in stimulated WB cultures. Measurements were corrected for mononuclear cell count. We also measured serum bone-specific alkaline phosphatase (ibAP) in all subjects. We found that LPS stimulated secretion of all cytokines both in WB and isolated cell cultures, and that this was attenuated by hydrocortisone. A significantly higher ratio of IL-1beta/IL-1ra (p = 0.02) in LPS stimulated WB cultures was seen in the untreated women. Levels of IL-1beta and IL-1alpha measured in WB cultures were lower and IL-1ra was higher in the ERT-treated group but these results were not significant. BAP was higher in the untreated group (p = 0.005) and correlated with IL-alpha/IL-1ra in the whole group (r = 0.49, p = 0.03). Results of other measurements showed no significant differences between groups. We conclude that estrogen may prevent bone loss following the menopause by altering the balance between IL-1beta and IL-1ra.  相似文献   

9.
In vivo effects of an imidazoline devoid of alpha2-adrenoceptor antagonistic properties, antazoline, on insulin secretion and glycemia were investigated both in fasted rats and dogs. In both species, antazoline (1.5 mg/kg i.v.) transiently increased insulinemia without affecting basal plasma glucose levels. In contrast, during an i.v. glucose tolerance test, antazoline markedly potentiated insulin release and thus increased the glucose disappearance rate. In rats, during an oral glucose tolerance test, the intragastric administration of antazoline (1.5 mg/kg) clearly enhanced insulin secretion and reduced hyperglycemia. In dogs provided with a venous pancreatico-duodenal bypass, antazoline (0.5 mg/kg i.v.) induced an immediate and transient increase in insulin and somatostatin but not in glucagon pancreatico-duodenal outputs. In conclusion, intravenously and orally administered, the imidazoline antazoline is able to stimulate insulin secretion in vivo and improve glucose tolerance. The imidazoline compounds could therefore have a potential therapeutic relevance as new antihyperglycemic insulinotropic agents.  相似文献   

10.
Quantitative determination of insulin secretion is of importance both clinically and in research. The optimal method has not been established, although several different methods have been used. We determined the reproducibility of islet function parameters obtained by the glucose-dependent arginine stimulation test, and also studied the priming effect of arginine on subsequent acute insulin responses. The test measures the acute insulin (AIR) and glucagon (AGR) responses to i.v. arginine (5 g injected over 45 s) at fasting glucose and glucose concentrations clamped at 14 and above 25 mmol/l, as well as the glucose potentiation of insulin secretion (slopeAIR) and the glucose inhibition of glucagon secretion (slopeAGR). When the test was performed twice in seven healthy women (mean +/- SD age 58.7 +/- 0.5 years, BMI 27.6 +/- 5.5 kg/m2), the AIRs to arginine had a within-subject coefficient of variation (CV) of 18.6% at fasting glucose, 18.7% at 14 mmol/l glucose and 16.3% at above 25 mmol/l glucose. The CVs for AGR were 11.6, 14.9 and 8.9%, respectively. The CV of the slopeAIR was 24% and of the slopeAGR 17.2%. The arginine priming study was performed in six healthy women (age 63.7 +/- 0.3 years, BMI 28.0 +/- 6.9 kg/m2). Saline or arginine (5 g) was injected at fasting glucose, followed by arginine (5 g) at 14 mmol/l glucose. There was no difference between the acute insulin or glucagon responses to arginine at 14 mmol/l glucose in the two conditions, suggesting that there is no priming effect of arginine on the subsequent acute insulin or glucagon responses. Therefore, this method is a good tool to determine insulin secretion as, apart from its good reproducibility, it also provides several important parameters of islet function.  相似文献   

11.
This study examines insulin and glucagon secretion in the basal state and in response to clofibrate therapy in patients with angiographically proven coronary artery disease. When compared with weight matched subjects without coronary artery disease, neither insulin nor glucagon secretion were abnormal in response to L-arginine stimulation. However, in response to clofibrate, a marked reduction in insulin secretion and simultaneous elevation in glucagon secretion characterized all patients. Our data suggest the hypothesis that altered insulin and glucagon secretion in response to clofibrate therapy may participate in the reduction of new coronary events reported to occur during therapy with this drug.  相似文献   

12.
Glucagon may regulate FFA metabolism in vivo. To test this hypothesis, six healthy male volunteers were infused with somatostatin, to inhibit endogenous hormone secretion, and insulin, glucagon, and GH to replace endogenous secretion of these hormones. In the hypoglucagonemia experiments, the glucagon infusion was omitted, and in the hyperglucagonemic experiments glucagon was infused at 1.3 ng/kg.min, to produce physiological hyperglucagonemia. In two sets of control experiments, glucagon was infused at 0.65 ng/kg.min, in order to maintain peripheral euglucagonemia, and the plasma glucose concentrations were clamped at the levels observed in either the hypo- or hyperglucagonemic experiments. Rates of FFA and glycerol (an index of lipolysis) appearance (Ra) were estimated with the isotope dilution method using [1-14C]palmitate and [2H5] glycerol. Plasma glucagon concentrations decreased during the hypoglucagonemic experiments (85 +/- 12 vs. 123 +/- 22 ng/L, P < 0.05) and increased during the hyperglucagonemic experiments (186 +/- 20 vs. 125 +/- 15 ng/L, P < 0.05), whereas other hormone concentrations remained the same. Hypoglucagonemia resulted in equivalent suppression of FFA Ra (3.7 +/- 0.2 vs. 5.9 vs. 0.3 mumol/kg.min, P < 0.01) and glycerol Ra (1.2 +/- 0.2 vs. 2.2 +/- 0.5 mumol/kg.min, P < 0.05). Similarly, hyperglucagonemia resulted in equivalent stimulation of FFA Ra (5.2 +/- 0.4 vs. 3.7 +/- 0.3 mumol/kg.min, P < 0.05) and glycerol Ra (1.5 +/- 0.3 vs. 1.1 +/- 0.1 mumol/kg.min, P < 0.05). These results indicate that glucagon has a physiological role in the regulation of FFA metabolism in vivo.  相似文献   

13.
Hypercortisolemia directly before the administration of endotoxin (LPS) to normal humans completely prevents the release of the proinflammatory cytokine tumor necrosis factor, whereas hypercortisolemia 12 h to 7 days before the injection of LPS is associated with enhanced tumor necrosis factor release. To determine the effect of elevated cortisol levels on the secretion of the antiinflammatory cytokine interleukin-10 (IL-10), 23 healthy men were given iv LPS (lot EC-5; 2 ng/kg) alone or in combination with a continuous iv infusion of hydrocortisone (3 micrograms/kg.min) for 6 h immediately before or 6, 12, or 144 h before LPS injection. LPS induced a monophasic increase in plasma IL-10 concentrations that peaked after 2 h (162 +/- 27 pg/mL; P < 0.0001). In subjects who were infused with hydrocortisone directly before LPS administration, IL-10 concentrations were much higher (1784 +/- 331 pg/mL; P < 0.0001 vs. LPS only), whereas hypercortisolemia 6, 12, or 144 h before LPS injection did not influence LPS-induced IL-10 levels. In human whole blood in vitro, hydrocortisone caused a dose-dependent reduction of LPS-induced IL-10 levels. Further, hydrocortisone reversed the increase in IL-10 concentrations by epinephrine in LPS-stimulated whole blood. Stimulation of IL-10 release may contribute to the antiinflammatory properties of glucocorticoids.  相似文献   

14.
The present studies were designed to test the hypothesis that arginine vasopressin (AVP) can interact with hydrocortisone and 3,5,3'-triiodothyronine (T3) to induce maturation of lung liquid reabsorptive processes in fetal sheep < 130 days gestation. Lung liquid production rates were measured in chronically catheterized thyroidectomized fetal sheep during eight different experimental treatments. Each experiment consisted of a 2-h control period followed by a 5-h treatment period. Net secretion or reabsorption of lung liquid was measured by using impermeant marker dilution techniques. AVP alone (50 mU/kg bolus plus 5.0 mU.kg-1.min-1 i.v. infusion) does not alter lung liquid secretion in fetal sheep 125 +/- 0.72 (SE) days gestation. In contrast, AVP (same dose as above) with T3 (30 micrograms) and hydrocortisone (6.94 mg/min) depressed lung liquid secretion and caused reabsorption of fluid. T3 alone, T3 and hydrocortisone, T3 and AVP, hydrocortisone alone, hydrocortisone and AVP, and saline did not result in net lung liquid reabsorption over a 5-h treatment period. These investigations demonstrate that AVP, T3, and hydrocortisone interact to cause lung liquid reabsorption in immature fetal lungs.  相似文献   

15.
This neonate developed marked hyperglycemia four days after birth and required insulin therapy for eight weeks. During the acute phase of the disease, immunoreactive insulin was undetectable in portal venous serum. Neither tolbutamide nor theophylline administration significantly triggered insulin secretion. Somatostatin infusion inhibited growth hormone release but had no effect on plasma glucagon or blood glucose concentrations. At 2 1/2 months, two weeks after insulin withdrawal, the infant was still intolerant to an oral glucose load, insulin response was markedly delayed, and growth hormone secretion was paradoxical. At five months, the insulin, glucagon, and growth hormone responses to glucose and to somatostatin were normalized. Thus, in this patient, insulin secretion was transiently deficient. Peculiarities of glucagon and growth hormone secretion were also present but are more characteristic of this age group than of diabetes. The hyperglycemic state was managed by intraportal infusion of 0.1 to 0.2 IU regular insulin/kg/hour. This mode of insulin administration proved efficient, secure, and easy to manage.  相似文献   

16.
The study investigated the respective influences of nicotinic acid and somatostatin on plasma concentrations of blood glucose, free fatty acids, glucagon, growth hormone and cortisol in insulin-dependent diabetic subjects. After administration of nicotinic acid alone, marked depression of plasma FFA was accompanied by significant increases of plasma glucagon, growth hormone and cortisol. The glucagon and growth hormone responses to nicotinic acid were significantly reduced when plasma FFA were raised by intravenous administration of heparin and triglycerides. Somatostatin alone induced a significant decrease in blood glucose, plasma glucagon and growth hormone concentrations. Plasma FFA remained unchanged. Somatostatin did not modify the nicotinic acid-induced fall in plasma FFA, but completely blocked the corresponding increments in glucagon and growth hormone. The cortisol rise was not altered by somatostatin. Rebound of glucagon and growth hormone levels were seen upon discontinuation of the somatostatin administration. These results demonstrate that the plasma FFA concentration plays a role in the regulation of glucagon and growth hormone secretion in insulin-dependent diabetics. Furthermore, they indicate that somatostatin, previously shown to be capable of negating the stimulatory effect of various factors on glucagon and growth hormone secretion, also affects the response of these hormones to FFA depression.  相似文献   

17.
Sixty minutes of restraint stress, preceded by chlorpromazine administration which stimulates somatotrophic hormone secretion (STH), produced an acute post-stress diabetic response (PDR) in normal-intact rats as well as in adrenalectomized rats. This PDR lasted 3 to 4 hours and was evaluated by glucemia and glucosuria determination and by the appearance of an insulin antagonist, alpha2-glycoprotein STH-dependent, called alpha2-inhibitor, which inhibits glucose uptake by isolated tissues. When tested in the suprahepatic blood of animals after stress it showed increased activity, both in normal and in adrenalectomized rats. This result permits us to state that alpha2-inhibitor may be produced in the liver by and action of STH and without primary glucocorticoid participation. The post-stress hyperglucemic response of adrenalectomized rats had a similar tendency to that of the control, although with initial and final values of glucemia significantly below the control. This response supports the diea that postadrenalectomy gluconeogenesis was evoked during and after the systemic stress.  相似文献   

18.
Glucagon-like peptide-1 (GLP-1 is an insulinotropic hormone, which is secreted from endocrine cells of the intestinal mucosa in relation to meal ingestion. It plays an important role as an incretin hormone; thus, mice with a null-muation in the gene encoding the GLP-1 receptor are glucose intolerant. In addition, GLP-1 inhibits gastrointestinal secretion and motility and is thought to act as one of the hormones of the "ileal brake". The insulinotropic effect of GLP-1 is preserved in patients with non insulin-dependent diabetes mellitus (NIDDM) and, because GLP-1 also inhibits glucagon secretion, it effectively lowers blood glucose in such, and given as an intravenous infusion it may completely normalise blood glucose. Furthermore, because its actions on insulin and glucagon secretion are dependent on the blood glucose levels it will not cause hypoglycemia. Efforts are therefore currently being made to employ GLP-1 or analogues thereof in clinical diabetes treatment, not least because recent investigations have shown that GLP-1, perhaps due to its gastrointestinal actions, is capable of reducing food intake in humans.  相似文献   

19.
OBJECTIVE: The purpose of this study was to evaluate the usefulness of 17 hydroxyprogesterone (17OHP) determination in dried filter paper blood samples from patients with congenital adrenal hyperplasia caused by 21-hydroxylase deficiency. It was hypothesized that these home samples would enhance patient treatment. STUDY DESIGN: Results of 17OHP determination in simultaneously collected venous and dried filter paper blood samples were compared to establish assay reliability. Thereafter, parents mailed dried filter paper blood samples collected before each hydrocortisone dose. RESULTS: The 17OHP levels in wet and dried blood samples correlated well (r = 0.98). Results did not change when stored for 2 weeks under various conditions. Blood sampling at different times of the day provided insights into the patterns of 17OHP secretion and identified times of inadequate adrenal suppression. Dose adjustments were then made considering the time of day when adrenal suppression was inadequate. CONCLUSION: Home monitoring of 17OHP is a reliable and practical approach for assessing adrenal steroid activity in patients with congenital adrenal hyperplasia. Considering the time of day of 17OHP elevations also facilitates hydrocortisone dosing adjustment.  相似文献   

20.
Studies are reviewed in which the roles of insulin and glucagon in normal physiology and in diabetes are examined. In normal man, glucose ingestion is accompanied by a rise in insulin and fall in glucagon and is primarily disposed of in the liver, an organ sensitive to both hormones. However, infusions of glucagon in physiologic amounts indicate that insulin secretion rather than glucagon inhibition is the primary factor determining glucose disposal. Furthermore, minor elevations in blood glucose elicit increments in insulin concentration and inhibition of hepatic glucose output in the absence of changes in plasma glucagon. The primary physiologic role of glucagon is to prevent the hypoglycemia that would otherwise accompany noncarbohydrate (protein)-mediated insulin secretion. In diabetic as well as normal patients the stimulatory effect of glucagon on hepatic glucose production is evanescent. Increases in glucagon or changes in the I/G ratio can bring about deterioration in glucose tolerance or in diabetic control only so long as absolute insulin deficiency is present or pharmacologic elevations in glucagon are produced. After somatostatin administration, prolonged hypoinsulinemia in normal subjects is observed to result in fasting hyperglycemia in the absence of basal glucagon secretion. In diabetic patients the improvement in postprandial hyperglycemia produced by somatostatin can be accounted for by its inhibitory action on carbohydrate absorption in the gastrointestinal tract. It is concluded that insulin deficiency is the primary pathophysiologic disturbance in diabetes. While glocagon may worsen the consequences of insulin lack, it is neither sufficient nor necessary for the development of diabetes.  相似文献   

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