scholarly journals Comparisons among old and new provocative tests of GH secretion in 178 normal adults

2000 ◽  
pp. 347-352 ◽  
Author(s):  
G Aimaretti ◽  
C Baffoni ◽  
L DiVito ◽  
S Bellone ◽  
S Grottoli ◽  
...  
Keyword(s):  
Low Dose ◽  
Adult Population ◽  
Ideal Body Weight ◽  
Normative Values ◽  
Gh Secretion ◽  
The Third ◽  
Ideal Body ◽  
The Mean ◽  
Age Range ◽  
Normal Adults

Classical provocative stimuli of GH secretion such as insulin-induced hypoglycaemia, arginine, clonidine, glucagon and levodopa have been widely used in clinical practice for approximately 30 years. On the other hand, in the last 10 years new potent stimuli of GH secretion have been proposed, but an extensive comparison with the classical ones has rarely been performed, at least in adults. In order to compare the GH-releasing activity of old and new provocative stimuli of GH secretion, and to define the normative values of the GH response, in 178 normal adults (95 males, 83 females; age range: 20-50 years, all within +/-15% of their ideal body weight), we studied the GH response to: insulin-induced hypoglycaemia (ITT, 0.1IU/kg i.v.), arginine (ARG, 0.5g/kg i.v.), clonidine (CLO, 300 microg/kg p.o.), glucagon (GLU, 1mg i.m.), pyridostigmine (PD, 120mg p.o.), galanin (GAL, 80pmol/kg per min), GH-releasing hormone (GHRH, 1 microg/kg i.v.), GHRH+ARG, GHRH+PD, hexarelin, a GH-releasing protein (HEX, 2 microg/kg i.v.) and GHRH+HEX (0.25 microg/kg i.v.). The mean (+/-s.e.m.) peak GH response to ITT (21.8+/-2.8, range: 3.0-84.0 microg/l) was similar to those to ARG (18.0+/-1.6, range: 2.9-39.5 microg/l) or GLU (20. 5+/-2.2, range: 10.6-36.9 microg/l) which, in turn, were higher (P<0. 001) than those to CLO (8.2+/-1.6, range: 0.3-21.5 microg/l), PD (9. 6+/-1.1, range: 2.2-33.0 microg/l) and GAL (9.3+/-1.1, range: 3.9-18. 3 microg/l). The GH response to GHRH (19.1+/-1.5, range: 2.7-55.0 microg/l) was similar to those after ITT, ARG or GLU but clearly lower than those after GHRH+ARG (65.9+/-5.5, range: 13.8-171.0 microg/l) and GHRH+PD (50.2+/-4.6, range: 17.7-134.5 microg/l) which, in turn, were similar. The GH response to HEX (55.3+/-5.5, range: 13.9-163.5 microg/l) was similar to those after GHRH+ARG and GHRH+PD but lower (P<0.001) than that after GHRH+HEX (86.0+/-4.3, range: 49. 0-125.0 microg/l) which was the most potent stimulus of GH secretion. In this adult population the third centile limits of peak GH response to various stimuli were the following: ITT: 5.3; ARG: 2.9; CLO: 1.5; GLU: 7.6; PD: 2.2; GAL: 4.0; GHRH: 5.0; GHRH+ARG: 17.8; GHRH+PD: 17.9; HEX: 21.6; GHRH+HEX: 57.1. These results confirm that, among classical provocative tests of GH secretion, ITT followed by ARG and GLU are the most potent ones and possess clear limits of normality. GHRH+ARG or PD and HEX are strong stimuli of GH secretion which, however, is maximally stimulated by a combination of GHRH and a low dose of HEX. It is recommended that each test is used with appropriate cut-off limits.

scholarly journals Comparison between Insulin-Induced Hypoglycemia and Growth Hormone (GH)-Releasing Hormone + Arginine as Provocative Tests for the Diagnosis of GH Deficiency in Adults1

1998 ◽  
Vol 83 (5) ◽  
pp. 1615-1618 ◽  
Author(s):  
G. Aimaretti ◽  
G. Corneli ◽  
P. Razzore ◽  
S. Bellone ◽  
C. Baffoni ◽  
...  
Keyword(s):  
Gh Deficiency ◽  
Clinical Context ◽  
Provocative Test ◽  
Female Age ◽  
Gh Secretion ◽  
The Third ◽  
Independent Test ◽  
The Mean ◽  
Normal Adults ◽  
Similar Peak

There is now wide consensus that, within an appropriate clinical context, GH deficiency (GHD) in adults must be shown biochemically by provocative testing of GH secretion and that appropriate cut-off limits have to be defined for each provocative test. Insulin-induced hypoglycemia (ITT) is indicated as the test of choice, and severe GHD, to be treated with recombinant human GH replacement, is defined by a GH peak response to ITT of less than 3 μg/L. GHRH + arginine (GHRH+ARG) is one of the most promising tests in alternative to ITT. In fact, it has been reported as a potent, reproducible, and age-independent test and that it is able to distinguish between GHD and normal adults. The aim of the present study was to compare the GH response to ITT and GHRH+ARG in a large group of hypopituitary adults (n = 40; 29 male and 11 female; age: 36.4 ± 2.1 yr). The third centile limit of the peak GH response to ITT has been reported as 5 μg/L, whereas in our lab, that to GHRH+ARG is 16.5 μg/L. In hypopituitary adults, the mean peak GH response to ITT (1.5 ± 0.2 μg/L, range: 0.1–8.5μ g/L) was lower (P &lt; 0.001) than that to GHRH+ARG (3.0 ± 0.4 μg/L, range 0.1–12.0 μg/L), though there was positive correlation (r = 0.61, P &lt; 0.001) between the GH responses to the 2 tests. The peak GH response to GHRH+ARG, but not that to ITT, was positively (though weakly) associated with insulin-like growth factor-I levels (r = 0.35, P &lt; 0.03). Childhood and adult onset GHD patients, as well as patients with single and multiple pituitary insufficiencies, had similar peak GH responses to ITT or GHRH+ARG. Analyzing individual GH responses, 4/40 (10%) of the hypopituitary patients had GH peaks higher than 5 μg/L after ITT; moreover, 3 other patients (7%) had GH peaks, after ITT, higher than 3 μg/L. On the other hand, after GHRH+ARG, all patients had GH peaks lower than 16.5 μg/L, whereas 21/40 (52.5%) had GH peaks higher than 3 μg/L. Because 3 μg/L is the arbitrary cut-off for ITT, the third centile limit of which is 5μ g/L, we arbitrarily considered 9 μg/L as the cut-off point for GHRH+ARG. It is noteworthy that 37/40 (92.5%) patients had a GH peak,. after GHRH+ARG, below this limit. In conclusion, our present results confirm that the ITT test is a reliable provocative test for the diagnosis of adult GHD, whereas they show that the GHRH+ARG test is, at least, as sensitive as the ITT test (provided that appropriate cut-off limits are considered). Note that even the arbitrary cut-off point below which severe GHD is demonstrated has to be appropriate to the potency of the test.

scholarly journals Low Dose Hexarelin and Growth Hormone (GH)-Releasing Hormone as a Diagnostic Tool for the Diagnosis of GH Deficiency in Adults: Comparison with Insulin-Induced Hypoglycemia Test1

1999 ◽  
Vol 84 (8) ◽  
pp. 2633-2637
Author(s):  
M. Gasperi ◽  
G. Aimaretti ◽  
G. Scarcello ◽  
G. Corneli ◽  
C. Cosci ◽  
...  
Keyword(s):  
Low Dose ◽  
Gh Deficiency ◽  
Normal Subjects ◽  
Diagnostic Reliability ◽  
Provocative Test ◽  
Gh Secretion ◽  
The Third ◽  
Normal Limits ◽  
Normal Ranges ◽  
The Mean

GH deficiency (GHD) in adults must be shown by provocative testing of GH secretion. Insulin-induced hypoglycemia (ITT) is the test of choice, and severe GHD, treated with recombinant human GH replacement, is defined by a GH peak response to ITT of less than 3 μg/L. GHRH plus arginine (ARG) is a more provocative test and is as sensitive as ITT provided that appropriate cut-off limits are assumed. GH secretagogues are a family of peptidyl and nonpeptidyl GH-releasing molecules that strongly stimulate GH secretion and, even at low doses, truly synergize with GHRH. Our aim was to verify the diagnostic reliability of the hexarelin (HEX; 0.25 μg/kg, iv) and GHRH (1 μg/kg, iv) test for the diagnosis of adult GHD. To this goal, in the present study we 1) defined the normal ranges of the GH response to GHRH+HEX in a group of normal young adult volunteers (NS; n = 25; 18 men and 7 women; age, 28.5 ± 0.6 yr) and in 11 of them verified its reproducibility in a second session, and 2) compared the GH response to GHRH+HEX with that to ITT in a group of normal subjects (n = 33; 12 men and 21 women; age, 34.1 ± 1.5 yr) and hypopituitaric adults with GHD (n = 19; 10 men and 9 women; age, 39.9 ± 2.2 yr; GH peak &lt;5 μg/L after ITT). The GH response to GHRH+ARG was also evaluated in all GHD and in 77 normal subjects (40 men and 37 women; age, 28.1 ± 0.6 yr). The mean GH peak after GHRH+HEX in NS was 83.6 ± 4.5 μg/L; the third and first percentile limits of the normal GH response were 55.5 and 51.2 μg/L, respectively). The GH response to GHRH+HEX in NS showed good intraindividual reproducibility. In GHD the mean GH peak after GHRH+HEX (2.6 ± 0.7 μg/L) was similar to that after GHRH+ARG (3.6 ± 1.0 μg/L), and both were higher (P &lt; 0.001) than that after ITT (0.6± 0.1 μg/L); the GH responses to GHRH+HEX were positively associated with those to ITT and GHRH+ARG. Analyzing individual GH responses, 100% had severe GHD after ITT (GH peak, &lt;3 μg/L). After GHRH+HEX all GHD had GH peaks below the third percentile limit of normality appropriate for this test (i.e. 55.5 μg/L). Thirteen of 19 (68.4%) GHD subjects had GH peaks below 3 μg/L after GHRH+HEX but all 19 (100%) had GH peaks below the first percentile limit of normality (i.e. 51.2 μg/L). The GH responses to GHRH+HEX were highly concordant with those after GHRH+ARG. In conclusion, the present results define normal limits of the GH response to stimulation with low dose HEX+GHRH in normal adults and show that this test is as sensitive as ITT for the diagnosis of adult GHD provided that appropriate cut-off limits are considered.

Urinary nitrogen excretion at the early stage of severe acute pancreatitis

2020 ◽  
Vol 21 (4) ◽  
pp. 131-134
Author(s):  
O. G. Sivkov ◽  
◽  
A. O. Sivkov ◽  
Keyword(s):  
Acute Pancreatitis ◽  
Severe Acute Pancreatitis ◽  
Early Stage ◽  
Ideal Body Weight ◽  
Nitrogen Excretion ◽  
The Third ◽  
Ideal Body ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen ◽  
The Ideal

Aim. To study urinary nitrogen excretion at the early stage of severe acute pancreatitis. Materials and methods. Prospective, single-center, cohort study. Inclusion criteria: diagnosis of acute pancreatitis and presence of at least one of the predictors of severe course. Among all patients (n = 72), a cohort of patients with severe acute pancreatitis (n = 32) was allocated. Three groups were formed in it: the first one – all patients, the second one – survivors (n = 24), the third one – deceased (n = 8). Urinary nitrogen excretion was determined using the Deacon formula. Measurements were performed on the first, third and fifth days of the disease. Statistical processing of the material was carried out by the SPSS software package. The null hypothesis was rejected at p < 0.05. Results. In the first week of the disease in all groups, the maximum urinary nitrogen excretion occurs on the 3rd day. When comparing the results of the second and third groups, it was found that the urinary nitrogen excretion on the first and fifth days did not have a statistically significant difference between the groups (respectively, p = 0.138, p = 0.572), and the results of the third day have (p = 0.014). A similar pattern remains when recalculating the nitrogen loss in the urine to the ideal weight; for the third day, the differences between the second and third groups were statistically significant (p = 0.007). ROC analysis of urinary nitrogen excretion of the third day calculated to the ideal body weight showed an area under the curve of 0.813 (p < 0.009). The value at the cut-off point is defined as 0.65 g/kg/day. The sensitivity of the model was 0.75%, specificity – 0.83%. Conclusion. If in a patient with acute pancreatitis, there is urinary nitrogen excretion on the third day from the onset of the disease, calculated to an ideal body weight of ≥ 0.65 g/kg/day, an unfavorable outcome of the disease is predicted.

scholarly journals The Effect of Age, Gender, Refractive Status and Axial Length on the Measurements of Hertel Exophthalmometry

2015 ◽  
Vol 9 (1) ◽  
pp. 113-115 ◽  
Author(s):  
Omer Karti ◽  
Ozlem B Selver ◽  
Eyyup Karahan ◽  
Mehmet O Zengin ◽  
Murat Uyar
Keyword(s):  
Axial Length ◽  
Adult Population ◽  
Mean Value ◽  
Normative Values ◽  
Length Standard ◽  
Refractive Status ◽  
Study Population ◽  
The Mean ◽  
Effect Of Age ◽  
Healthy Females

Purpose : To evaluate the normal distribution of exophthalmometric values in Turkish adult population and the effect of age, gender, refractive status and axial length on globe position. Methods : One hundred and twenty-two males and 114 healthy females with age ranging from 18 to 87 years were included in the study. The study population was recruited from patients presenting to our institution for routine refractive examination. Hertel exophthalmometer was used to measure the degree of ocular protrusion. Effect of age, refractive error, interpupillary distance, and axial length on globe position was detected with linear regression analyses. Results : The mean Hertel exophthalmometric size was 15.7+2.6 mm (range; 11 to 21 mm). The mean value for males was 16.1±2.6 mm (range; 11 to 21 mm), and for females 15.5±2.6 mm (range; 11 to 20 mm). The mean distance between the lateral rims of the orbit was 102 + 5.1 mm (range; 88 to 111mm). The mean exophthalmometric values were not statistically different in males and females. Age and mean spherical equivalents were negatively correlated with exophthalmometric measurements. Axial length was positively correlated with exophthalmometric measurements. Conclusion : The exophthalmometric measurement of the eye is affected by the age, spherical equivalent and the axial length. Standard normative values of the Hertel exophthalmometric measurements should be reevaluated with larger samples.

Therapeutic Drug Monitoring (TDM) of IV Busulfan in Patients with Severe Obesity.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1990-1990
Author(s):  
Donald A. Hutcherson ◽  
Jolynn K. Sessions ◽  
Ronald A. Mihelic ◽  
Katherine Sanvidge ◽  
Stephen R. Stricker ◽  
...  
Keyword(s):  
Body Weight ◽  
Severe Obesity ◽  
Package Insert ◽  
Ideal Body Weight ◽  
Obese Patients ◽  
Actual Weight ◽  
Severely Obese ◽  
Ideal Body ◽  
The Mean ◽  
Dosing Strategy

Abstract It has been previously reported that increases in relapse and graft rejection can be associated with a low busulfan area under the curve (AUC) and hepatic toxicities are associated with a high AUC. This has lead to strategies to adjust busulfan dosing to achieve a target AUC. A retrospective analysis was performed in patients with severe obesity, defined as a Body Mass Index (BMI) greater than 40, to evaluate the reliability of IV busulfan dosed using the package insert dosing strategy to reach a targeted AUC. The study included 11 females and 8 males who received IV busulfan as part of their hematopoietic progenitor cell transplant preparative regimen. There were 11 autologous and 8 allogeneic transplants for lymphoma (10) and leukemia (9). The mean and median ages were 38 and 41 years (range 19–51). The mean and median BMIs for this population were 47.8 and 46.2 (range 40.4–62.7). The mean and median weights were 139.5 kg and 142.5 kg (range 107–192.3). TDM was performed with the first dose of busulfan along with subsequent dosage adjustments to achieve a target AUC of 1150–1350 micromol X min/L. Busulfex package insert dosing recommendations are for 16 doses of 0.8 mg/kg (12.8 mg/kg) using an adjusted ideal body weight (AIBW) for obese patients. AIBW = 0.25 × (actual weight − ideal body weight) + ideal body weight. Using the AIBW dosing, the mean starting dose to actual body weight ratio was 0.48 mg/kg (range 0.40–0.55 mg/kg). Based on the AUC analysis, the predicted mean AUC using the AIBW dosing was 972 (range 702–1356). Six AUCs were below 900, 10 AUCs were above 900 but below 1150, 2 AUCs were within the target range and 1 AUC was greater than 1350. Thirteen of the patients had repeat AUC analyses following a subsequent dose to confirm that the dose adjustments achieved the targeted AUCs. Seven of these patients had further dose adjustments following the repeat AUC analysis. Five patients with a busulfan mean half-life of 235 minutes (range 218–247 minutes) had higher AUCs than the rest of the group. The mean and median AUCs for these 5 patients were 1177 and 1223 (range 997–1357). The remaining 14 patients with a mean busulfan half-life of 177 minutes (range 151–201) had mean and median AUCs of 899 and 903 (range 702–1105). The total therapy delivered ranged from 12.7 to 21.4 mg/kg based on the AIBW. When calculated on actual weight, the range was 6.9 to 11.24 mg/kg. Conclusion: The AIBW dosing strategy of IV busulfan is inadequate to achieve the targeted AUC of 1150–1350 in severely obese patients. Severely obese patients require dose increases in the majority of cases, while those with delayed clearance could be overdosed if higher doses are administered without TDM. Severely obese patients require TDM and the majority will require dosage adjustments to administer IV busulfan in the targeted therapeutic range.

scholarly journals Effect of Age on Pentacam Keratoconus Indices

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Maged Maher Salib Roshdy ◽  
Sherine Shafik Wahba ◽  
Rania Serag Elkitkat ◽  
Amira Maurice Hakim ◽  
Ramy Riad Fikry
Keyword(s):  
Retrospective Study ◽  
Important Determinant ◽  
Normal Subjects ◽  
Normative Values ◽  
The Third ◽  
Age Range ◽  
Effect Of Age

Purpose. To assess the effect of age on elevation and pachymetric Pentacam keratoconus (KC) detection indices, and the need to adjust normative values accordingly. Methods. In a retrospective study, 95 eyes of myopic normal subjects without KC were evaluated using the OCULUS Pentacam, with an age range of 17.4 to 46.8 years. Subjects were categorised into three groups according to their age: the first included those younger than 21 years (19 eyes), the second was for the age range of 21–40 years (65 eyes), and the third comprised subjects older than 40 years (11 eyes). Results. There were statistically significant differences among the three groups regarding many elevation indices: AE from BFS, PE from BFS, and PE minus AE from BFS (P=0.003, 0.010, and <0.001, resp.), and pachymetric indices: PPI avg, PPI max, ART avg, ART max, and diagonal decentration of the thinnest point (P=<0.001, 0.024, 0.003, 0.026, and 0.026, resp.). On comparing subjects below 21 years to those above 40 years, there was a statistically significant decrease of both PE from BFS and PE minus AE (P=0.005 and <0.001, resp.) and statistically significant increase in AE from BFS (P=0.001). Conclusions. Age is an important determinant of elevation indices, significantly altering their normative values. The use of the more robust pachymetry, rather than elevation, indices is recommended in subjects below 21 or above 40 years of age.

scholarly journals Odontoid process inclination in normal adults and in an adult population with Chiari malformation Type I

2015 ◽  
Vol 23 (6) ◽  
pp. 701-706 ◽  
Author(s):  
David A. Besachio ◽  
Ziyad Khaleel ◽  
Lubdha M. Shah
Keyword(s):  
Chiari Malformation ◽  
Pediatric Population ◽  
Adult Population ◽  
Odontoid Process ◽  
Normative Values ◽  
Control Group ◽  
Type I ◽  
Chiari Malformation Type I ◽  
Significant Difference ◽  
The Mean

OBJECT Posterior odontoid process inclination has been demonstrated as a factor associated with Chiari malformation Type I (CM-I) in the pediatric population; however, no studies to date have examined this measurement in the adult CM-I population. The purpose of this study was to evaluate craniocervical junction (CCJ) measurements in adult CM-I versus a control group. METHODS The odontoid retroflexion, odontoid retroversion, odontoid height, posterior basion to C-2 line measured to the dural margin (pB-C2 line), posterior basion to C-2 line measured to the dorsal odontoid cortical margin (pB-C2* line), and clivus-canal angle measurements were retrospectively analyzed in adult patients with CM-I using MRI. These measurements were compared with normative values established from CT scans of the cervical spine in adults without CM-I. RESULTS A statistically significant difference was found between 55 adults with CM-I and 150 sex-matched controls (125 used for analysis) in the mean clivus-canal angle and the mean pB-C2 line. CONCLUSIONS These data suggest that there are sex-specific differences with respect to measurements at the CCJ between men and women, with women showing a more posteriorly inclined odontoid process. There were also differences between the CM-I and control groups: a more acute clivus-canal angle was associated with CM-I in the adult population. These CCJ findings could have an influence on presurgical planning.

Abstract P210: Weight and Body Image Perceptions in Young, Low Income Adult Latinas with Imprecise Body Mass Index Classification

Circulation ◽  
2014 ◽  
Vol 129 (suppl_1) ◽  
Author(s):  
Jen Rinaldo ◽  
Erika Froelicher ◽  
Catherine Waters ◽  
Kirsten Bibbins-Domingo ◽  
Nancy Stotts
Keyword(s):  
Body Mass Index ◽  
Body Image ◽  
Body Weight ◽  
Body Dissatisfaction ◽  
Low Income ◽  
Body Satisfaction ◽  
Ideal Body Weight ◽  
Excess Weight ◽  
Ideal Body ◽  
The Mean

Introduction: Mexican American women in the US have the second highest prevalence of overweight or obesity (78.2%), 44.8% are obese, yet little research has examined the relationship between body mass index (BMI) and body satisfaction among young, low-income Latina adults. Objective: To examine the relationships between knowledge, attitudes, beliefs, and behaviors about weight, body image and excess weight. Hypothesis: We hypothesized that (1) the women would incorrectly classify BMI; (2) the majority would be obese and (3) there is no difference in body satisfaction among those with and without excess weight. Methods: A cross-sectional study with a convenience sample of 131 self-identified Latina women, ages 18 to 45 years was used from two Northern California clinics. An interview administered questionnaire assessed demographics, weight and body image. Statistical analysis included descriptive statistics, chi-square statistics, and logistic regression analysis. Results: While 31% (n=41) classified themselves as having a healthy BMI, 21% (n= 27) met the criteria. Although 58% (n=77) classified themselves as overweight, 46% (n=60) met the criteria. Although 2% (n=3) classified themselves as obese, 34% (n=44) were obese. The majority of women (67%; n=88) reported that they were not at their ideal body weight. Of those who wanted to lose weight, the mean number of pounds they would have to lose to be at their ideal body weight was 15.5 (± 16). The mean body dissatisfaction score of those with excess weight was 2.2 (± 1.1) and 0.74 (± 1.4) for those with healthy BMI. Conclusions: Most women underestimated their BMI category. Less than 6% (n=3) of obese women correctly classified themselves as obese. The misclassification and underreporting of excess weight was statistically significant (p≤ 0.05), pointing to a need for education about weight. Body dissatisfaction scores were higher in women with excess weight. Actual/current body silhouette sizes were statistically significantly associated with excess weight: (OR=2.78, 95% CI: 1.28, 6.04, p= 0.02).

The Identification of Malnutrition in Heart Failure Patients

2002 ◽  
Vol 1 (2) ◽  
pp. 139-147 ◽  
Author(s):  
Sandra M. Nicol ◽  
Diane L. Carroll ◽  
Carol M. Homeyer ◽  
Colleen M. Zamagni
Keyword(s):  
Heart Failure ◽  
Gastrointestinal Symptoms ◽  
Ideal Body Weight ◽  
Clinical Parameters ◽  
Convenience Sample ◽  
Electrical Bioimpedance ◽  
Skinfold Measurement ◽  
Ideal Body ◽  
The Mean ◽  
Mean Heart Rate

Heart failure (HF) is the only cardiovascular disease that is increasing in incidence, prevalence, and mortality. One of the major complications associated with HF is malnutrition. Fluctuations due to fluid make weight measurement an inaccurate parameter to identify malnutrition. Therefore, the purpose of this study is to assess clinical parameters that could assist in the recognition of malnutrition in HF patients. A convenience sample of 50 HF patients had anthropometric measurements, a review of their serum chemistry levels, a collection of standard hemodynamic measures plus electrical bioimpedance, and, each subject completed a gastrointestinal symptoms assessment with two meals. Eighteen (36%) subjects were classified as malnourished based on the selected criteria of a serum albumin <3.0 g/dl and/or being less than 90% of ideal body weight. Within this sample of malnourished subjects, 44% of the subjects were found to be obese based on skinfold measurement. A comparison between malnourished/not malnourished groups found that the mean heart rate was higher in the malnourished group (85 vs. 73 beats/min; P<0.017). There were no other parameters that differentiated between these groups. These results demonstrate the need for further research to identify predictive clinical parameters for malnutrition in this vulnerable population.

Growth hormone (GH) secretion in the dwarf rat: release, clearance and responsiveness to GH-releasing factor and somatostatin

1990 ◽  
Vol 127 (1) ◽  
pp. 69-75 ◽  
Author(s):  
D. F. Carmignac ◽  
I. C. A. F. Robinson
Keyword(s):  
Low Dose ◽  
Gh Deficiency ◽  
Peak Plasma ◽  
Female Rats ◽  
Disappearance Rate ◽  
Gh Secretion ◽  
Fold Reduction ◽  
Plasma Gh ◽  
Age Range ◽  
Dose Dependent

ABSTRACT The new mutant GH-deficient dwarf (Dw) rat was used to study the effects of GH-releasing factor (GRF) or somatostatin (SRIF) on GH release. In anaesthetized adult Dw female rats, i.v. injections of GRF (0·031–2·0μg) elicited a dose-dependent release of GH. Although the peak plasma GH responses to maximal GRF doses were much lower in adult Dw rats compared with normal rats of this strain (AS), the responses largely reflected their relative pituitary GH contents (140±17 μg vs 2·9±0·4 μg, AS vs Dw (means ± s.e.m.), P < 0·001). Except at 20 days of age, normal AS rats were more sensitive to GRF than Dw rats despite their larger body weight. Peak GH responses to injection of 31·25 ng GRF increased nine-fold in normal rats between 20 and 40 days, whereas the GH responses to this GRF dose diminished in Dw rats over this age range, and their pituitary GH content was only 2–5% of that of age-matched AS rats. Treatment with human GH (200 μg/day for 7 days) stimulated growth in 40-day-old Dw rats and slightly increased the GH response to a low dose of GRF. Basal GH levels in adult Dw animals were sevenfold lower than in AS rats (2·4±0·3 vs 17·6±3·3 μg/l P < 0·001) and were further suppressed by i.v. infusion of SRIF (25 μg/h). As in normal rats, a rebound GH secretion occurred in Dw rats after stopping SRIF, which was blocked by injection of anti-GRF serum. The disappearance rate of 125I-labelled rat GH from plasma was identical in AS and Dw rats. We conclude that dwarf rats show GH deficiency as early as 20 days of age; they respond to GRF, but release only small amounts of GH due to their reduced pituitary GH content. Although basal GH release is reduced in Dw rats, the levels are higher than would be expected from the 50-fold reduction in pituitary stores, and may reflect a chronic reduction in SRIF and/or increase in GRF release induced by prolonged GH deficiency in the Dw rat. Journal of Endocrinology (1990) 127, 69–75

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