Serum Growth Hormone Response Research Articles

Selective impairment of growth hormone response to physiological stimuli.

In a consecutive group of 25 children with defective growth being evaluated for growth hormone deficiency, EEG-monitored slow-wave sleep provided discriminatory serum growth hormone responses equivalent to those obtained by arginine and insulin-hypoglycaemia provocation. Exercise was less effective but was able to provide a useful screening test. In 2 subjects with abnormal physiological but normal pharmacological serum growth hormone responses, therapeutic administration of growth hormone in one resulted in a significant growth increment, whereas in the other, advanced epiphyseal maturity precluded adequate evaluation. A normal growth hormone response to a pharmacological stimulus does not exclude a therapeutic response to human growth hormone.

Effect of illness on serum growth hormone response to intravenous glucose

Intravenous glucose was given to nine control patients, 16 ill patients without malignancy, and 20 patients with localized or metastatic malignancy to study hGH responses. All of the controls showed normal hGH suppression 1 hr after glucose. A paradoxical rise in hGH levels 1 hr after glucose was observed in the group of ill patients without tumors ( p < 0.05) and the group with malignancy ( p < 0.05) when each group was compared with the control group. Elevated plasma cortisol levels and a severe degree of illness correlated positively with the paradoxical hGH response, while plasma free fatty acids and insulin showed no correlation. These studies suggest that hGH levels may paradoxically rise soon after intravenous glucose in ill patients with or without malignant disease, and the paradoxical response is not specifically related to etiology but rather is a result of the stress of significant illness acting on the hypothalamus-anterior pituitary.

Fasting Serum Growth Hormone Levels and Growth Hormone Responses to Exercise during Normal Menstrual Cycles and Cycles of Oral Contraceptives

Fasting Serum Growth Hormone Levels and Growth Hormone Responses to Exercise during Normal Menstrual Cycles and Cycles of Oral Contraceptives

Responsiveness of Human Subjects to Human Growth Hormone: Relation to Bone Age

ABSTRACT In 3 types of short children, the effect of 7 days' treatment with human growth hormone (hGH) on daily balances of N, P, Na and K and on body weight was measured. Group I consisted of 17 children with short stature (<3rd percentile) and retarded bone age (<80% of chronologic age) caused by growth hormone (GH) deficiency; Group IIa, 10 children with short stature, normal serum GH response to insulin and arginine, and normal bone age; Group IIb, 9 children with short stature, normal serum GH response to insulin and arginine, and retarded bone age. Four daily doses of hGH were used: A, 0.0168 U/kg body wt3'4; B. 0.0532 U/kg body wt¾; C, 0.168 U/kg body wt¾; D, 0.532 U/kg body wt¾. At each dose, responses by Group I were 1.5 to 3 times greater than those of Group IIb and responses of Group IIb were 3 to 4 times greater than those of Group IIa. The data show that in short children with normal serum growth hormone response to insulin and arginine, responsiveness to hGH is proportional to degree of reta...

Immunoreactive Serum Insulin and Growth Hormone Response in Patients with Preinfarction Angina and Acute Myocardial Infarction

Levels of fasting growth hormone (GH), immunoreactive insulin (IRI) and glucose (FBS) were determined in 18 patients with acute myocardial infarction (AMI) and six patients with preinfarction angina on the day of admission to the hospital. The GH levels were within normal limits for the patients with AMI and preinfarction angina. Five of 18 patients with AMI and three of six patients with preinfarction angina had elevated levels of IRI, and one of 18 patients with AMI had IRI values below normal. None of the patients with preinfarction angina had hyperglycemia, but eight of 18 patients with AMI (44 percent) had elevated FBS levels. Of these eight patients with hyperglycemia, two had elevated IRI levels and six had values within normal limits. Thus, hyperglycemia in the two patients with elevated IRI levels was not attributable to hypoinsulinemia, but was due to other factors. The IRI levels did not correlate well with arrhythmias, Peel's prognostic score, clinical failure or cardiomegaly. GH levels were within normal limits in patients with AMI as well as preinfarction angina, and all survived. It is concluded that fasting-GH and IRI levels are similar in patients with AMI, and preinfarction angina and may indirectly indicate an equal degree of stress in these two disease states. Secondly, the presence of hyperglycemia in patients with AMI is not always related to insulin suppression, and may be due to other factors. Levels of fasting growth hormone (GH), immunoreactive insulin (IRI) and glucose (FBS) were determined in 18 patients with acute myocardial infarction (AMI) and six patients with preinfarction angina on the day of admission to the hospital. The GH levels were within normal limits for the patients with AMI and preinfarction angina. Five of 18 patients with AMI and three of six patients with preinfarction angina had elevated levels of IRI, and one of 18 patients with AMI had IRI values below normal. None of the patients with preinfarction angina had hyperglycemia, but eight of 18 patients with AMI (44 percent) had elevated FBS levels. Of these eight patients with hyperglycemia, two had elevated IRI levels and six had values within normal limits. Thus, hyperglycemia in the two patients with elevated IRI levels was not attributable to hypoinsulinemia, but was due to other factors. The IRI levels did not correlate well with arrhythmias, Peel's prognostic score, clinical failure or cardiomegaly. GH levels were within normal limits in patients with AMI as well as preinfarction angina, and all survived. It is concluded that fasting-GH and IRI levels are similar in patients with AMI, and preinfarction angina and may indirectly indicate an equal degree of stress in these two disease states. Secondly, the presence of hyperglycemia in patients with AMI is not always related to insulin suppression, and may be due to other factors.

Fasting Serum Growth Hormone Levels and Growth Hormone Responses to Exercise during Normal Menstrual Cycles and Cycles of Oral Contraceptives

Fasting growth hormone (GH) levels and GH responses to exercise were studied in normally menstruating women and in women taking oral contraceptives in order to find out whether the GH levels were related to the menstrual cycle or changed by oral contraceptives. The GH response to exercise was found to be higher when exercise was done in the midcycle period than when it was done at other points of time during the normal menstrual cycle. Fasting GH levels were unchanged throughout the menstrual cycle. Fasting GH levels and GH responses to exercise performed outside the midcycle period were identical in normally menstruating women and in women taking oral contraceptives. In conclusion, the GH response to exercise, but not fasting GH levels, were related to the menstrual cycle. The estrogen and progestin components of the contraceptives used in this study were balanced in such a way that the growth hormone levels and growth hormone responses to exercise were not changed by long-term therapy with these drugs.

Human growth hormone secretion after double stimulation with arginine in normal and insulin-dependent diabetic women.

The standard intravenous arginine test was modified by infusing two equal doses of arginine eighty minutes apart. The serum growth hormone, blood glucose and plasma free fatty acid responses were studied in fifteen young juvenileonset diabetic women and in seven healthy women of comparable age and weight. The biphasic growth hormone response to the two arginine infusions observed in normals did not occur in the diabetics. In addition, the diabetics differed from the normals in several qualitative aspects of growth hormone secretion. A derangement in the diabetic is postulated with impaired sensitivity or defective mechanism of growth hormone secretion. Diabetics with chronically elevated blood glucose levels had a blunted growth hormone response to arginine. In five patients with diabetic retinopathy, growth hormone response was somewhat blunted, probably due to higher blood glucose levels, as compared with findings in five patients without this complication.

Abnormal serum growth hormone response to exercise in maturity-onset diabetics.

Serum growth hormone was studied during a mild exercise load of 350 kgm. per minute for twenty minutes in four groups of subjects: nonobese normal subjects, obese normal subjects, nonobese maturity-onset diabetics and obese maturity-onset diabetics. It was found that (1) the fasting pre-exercise serum growth hormone level was higher and the exercise response occurred earlier and was greater in diabetics than in normal subjects; (2) in the nonobese groups, the basal values and exercise responses in diabetics were significantly different from those of normal individuals. In the obese groups, the mean exercise response was higher in diabetics than in normals, but this difference was not significant; the basal values were identical in the two groups; and (3) the basal values and exercise responses were higher in nonobese diabetics than in obese diabetics. In normal subjects, the exercise responses were higher in the nonobese group than in the obese group.

Serum insulin and growth hormone response to arginine infusion in healthy and psoriatic persons.

Serum insulin and growth hormone responses to intravenous infusion of arginine were measured in 10 normal control persons and 13 age- and weight-matched nondiabetic psoriatics. The average peak insulin levels, 58.2 μU/ml for normal controls and 47.8 μU/ml for the psoriatics, were recorded at 30 min. The average growth hormone peak values, 20.1 ng/ml for normal controls and 17.8 ng/ml for the psoriatics, were recorded in most cases in 60 min. No significant differences were obtained between the normal controls and psoriatics.

Serum growth hormone response to exercise in non-obese and obese normal subjects.

AbstractThe serum growth hormone response to a very mild, but prolonged exercise load – 225 kgm/min for 60 minutes – has been studied in 6 young non-obese healthy male subjects and 6 young obese healthy male subjects. The exercise load was easily tolerated by all subjects, and pulse rates at rest and during exercise were not much different in the two groups. The exercise-induced growth hormone rise in the non-obese subjects was discernible 30 minutes after start of work, and the maximum value of 26 ng/ml was reached 10 minutes after cessation of work. In contrast, no rise at all was seen in any of the obese subjects. It is thus demonstrated that exercise is similar to other growth-hormone-releasing stimuli: their potency is reduced in obesity.

Anxiety, growth hormone and glucose tolerance in normal children.

Abstract Serum growth hormone and insulin responses to oral and i.v. glucose have been measured in 13 schoolchildren who had normal but relatively low oral glucose tolerance as judged from a preliminary study of a total population of 320 schoolchildren. The results were compared with those from 13 children paired for sex, age, weight and height but having average glucose tolerance. Serum growth hormone curves showed an initial peak starting before glucose ingestion in both groups. The rise was significantly higher in oral as well as i.v. glucose tolerance tests in the group with relatively low tolerance. This group had also a tendency to higher serum insulin values. It is suggested that the low carbohydrate tolerance in these children is produced by high growth hormone secretion, elicited by emotional lability.

Serum insulin and growth hormone responses in the patients with liver cirrhosis.

Serum insulin and growth hormone responses in the patients with liver cirrhosis.

The serum insulin and growth hormone response to arginine and to arginine with glucose in the premature infant.

Serum insulin and human growth hormone (HGH) levels were measured in 33 premature infants during the first 24 hours of life, following the infusion of arginine, glucose, and glucose plus arginine. Infusion of arginine (2.5 g) was followed by a moderate early rise in serum insulin and a marked and delayed rise in serum HGH. Glucose (1.25 g) infusion resulted in a small insulin response and a rise of serum HGH. However the simultaneous administration of arginine and glucose, each in amounts of 1.25 g, was associated with a prompt marked rise of serum insulin and a delayed rise of serum HGH.

Normalization of growth hormone hyperresponse to exercise in juvenile diabetics after "normalization" of blood sugar.

The serum-growth hormone response to exercise is greater and occurs earlier in juvenile diabetics than in nondiabetics. A simple exercise test has been devised which unequivocally reveals the growth hormone hypersecretion of juvenile diabetics. Using this procedure we have shown that after a period of exceedingly strict metabolic control of the diabetes, complete normalization of growth hormone secretion is attained. It is concluded that the abnormalities in serum growth hormone found in juvenile diabetics are of a metabolic origin.

The effect of puberty on growth hormone secretion in boys with short stature and delayed adolescence.

Summary The effect of puberty on pituitary function, with particular reference to growth hormone (GH) and luteinising hormone (LH) secretion, was assessed in eight boys presenting with short stature and delayed onset of puberty. Six patients underwent spontaneous puberty, one was treated with testosterone, and the eighth was treated with human chorionic gonadotrophin (HCG). In the prepubertal state the peak serum GH levels achieved in response to insulin induced hypoglycaemia ranged from 0.4 to 2.4 ng/ml (mean 1.32 ± 0.66 SD) and were similar to levels observed in children with organic hypopituitarism. After the onset of spontaneous or induced puberty, there was a rapid increase in growth rate associated with a significantly increased peak serum GH response (P <.01) to hypoglycaemia ranging from 7.0 to 16 ng/ml with a mean of 9.6 ± 2.6 SD. These studies indicate that short stature and delayed puberty are not always “physiological” but may represent a state of reversible, functional hypopituitarism and that repeated measurements of the serum GH response to insulin hypoglycaemia after testosterone priming may be helpful in differentiating these children from those with other forms of hypopituitarism.

Effect of propranolol on the response of serum growth hormone to glucagon.

ABSTRACT In normal subjects the response of serum growth hormone to the intramuscular or subcutaneous injection of glucagon was augmented by a single oral dose of propranolol (40 mg) given 2 hours before injection. In addition, propranolol induced a normal response of serum growth hormone to glucagon in the few normal persons failing to respond to glucagon alone. Although approximately 90% of normal persons respond to glucagon alone with a rise in serum growth hormone, oral propranolol increases the percentage and thus enhances the value of the glucagon stimulation test in detecting a deficiency of growth hormone. This conclusion is reinforced by the lack of response in hypopituitarism and the conversion of a poor to a normal response in 1 of 2 patients with primary hypothyroidism when propranolol was added to the glucagon stimulation test.

Serum insulin and growth hormone response to hemorrhagic shock.

Many metabolic abnormalities, including hyperglycemia and glucose intolerance, occur in hemorrhagic shock, which has been previously reported in dogs to be accompanied by elevations in plasma insulin levels. In this study, large primates (baboons) were subjected to hemorrhagic hypotension for 2 hr, during which time marked hyperglycemia occurred. Within 5 min of the onset of hemorrhage, insulin levels declined substantially in both fed and fasted animals and remained below preshock levels during the first hour of shock. During the second hour, insulin levels gradually rose, reaching levels slightly above base line values in approximately half the animals studied. Insulin response to intravenous tolbutamide was subnormal when administered after 1 hr of hypotension. Growth hormone levels remained suppressed in the majority of animals studied, and in the remaining animals changes in growth hormone levels did not correlate well with fluctuations in glucose concentration. These studies demonstrate that hemorrh...

Corticosteroid and growth hormone secretion in patients treated with L-dopa.

Corticosteroid and growth hormone release were studied in 5 patients receiving L-dihydroxyphenylalanine (L-dopa) for the treatment of Parkinson's disease. Evaluation consisted of urinary steroid determinations and measurements of plasma 11-hydroxycorticosteroid (11-OHCS) and serum growth hormone responses to insulin hypoglycemia before and during treatment with L-dopa. No significant abnormality in plasma 11-OHCS or growth hormone secretion was detected in Parkinsonian patients before treatment. During treatment with L-dopa, 3 of 5 patients had a lower plasma 11-OHCS response to hypoglycemia than before treatment. One patient showed no plasma 11-OHCS rise at all after 4 weeks of L-dopa therapy. Growth hormone responses to hypoglycemia were not affected by administration of L-dopa. This preliminary study provides support for the hypothesis of a central adrenergic neural system inhibiting ACTH secretion in man.

A comparison of response of serum growth hormone to glucagon and vasopressin

The response of serum growth hormone (GH) to aqueous vasopressin is not as reliable as the response to glucagon and vasopressin did not elicit a response in any patient failing to respond to glucagon. Estrogen did not improve the response to either agent and blunted the response to glucagon in some subjects.

Effect of adolescence on the serum growth hormone response to hypoglycemia

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