Growth Hormone Secretion In Children Research Articles

OR14-4 Acute sleep disruption does not diminish pulsatile growth hormone secretion in pubertal children

Abstract Context: Growth hormone (GH) plays a critical role in glucose homeostasis and linear growth during childhood. GH secretion is controlled by multiple neurotransmitters and hormones. Sleep is also a powerful stimulus for GH secretion. In children, GH pulses occur after sleep onset in association with slow-wave sleep (SWS), but it is unclear if undisrupted sleep is required for normal GH secretion. Given the rising incidence of pediatric sleep disorders such as obstructive sleep apnea (OSA) that cause sleep fragmentation, it is critical to determine whether sleep fragmentation during childhood may dysregulate the somatotropic axis. Objective To quantify how undisrupted vs fragmented sleep affects GH secretion in children. Methods Pubertal subjects (10 M, 9 F; 9.1-14.4 yrs) were randomized to two overnight polysomnographic studies with frequent blood sampling (q10min) to measure GH: fourteen were healthy subjects studied with or without SWS disruption via auditory stimuli (3 sec, 1500 Hz tones, 40-100 dB followed by 18 sec of a 75 dB noise simulating a knock on the door) and five were subjects with OSA studied with or without prescribed continuous positive airway pressure (CPAP); the latter condition was expected to have sleep fragmentation due to untreated OSA. GH pulses were identified using sparse deconvolution. Studies without auditory stimuli or when using CPAP were combined and analyzed as 'undisrupted sleep'. The relationship between GH pulse rate per hour and sleep stage was evaluated using Poisson generalized estimating equations. Results In SWS disruption studies, an average of 77.51 ± 13.61 (range 23-190) auditory stimuli were delivered, causing a 40.02 ± 7.78% decrease in SWS in favor of lighter sleep stages. In subjects with OSA, CPAP withdrawal caused a slight increase in the apnea hypopnea index (1.08 ± 0.10 vs. 2.20 ± 1.70 events/hour of sleep, p=0.07) with no change in sleep stage durations. During undisrupted sleep, subjects had an average of 0.91 ± 0.067 GH pulses/hour with a mean pulse amplitude of 10.03 ± 1.00 ng/mL and mean basal secretion rate of 0.26 ± 0.10 ng/ml per min. GH pulses occurred more frequently during SWS (2.3 pulses/hour SWS, amplitude 9.92 ± 2.59 ng/mL) than during any other sleep stage (P < 0.001). Neither form of sleep disruption affected the distribution of GH pulses across sleep stages, GH pulse amplitude and frequency, nor basal GH secretion. Conclusion In children, nocturnal GH pulses are temporally associated with SWS. However, neither acute fragmentation of SWS nor nocturnal arousals from OSA altered basal or pulsatile GH secretion, indicating that somatotrophic axis activity is preserved in the face of acute sleep disruption in children. Presentation: Sunday, June 12, 2022 11:45 a.m. - 12:00 p.m.

High-intensity interval exercise test stimulates growth hormone secretion in children

Backgroundexercise stimulates growth hormone (GH) secretion and may serve as a promising physiological test for the diagnosis of GH deficiency. However, exercise standardization for a feasible GH test is still lacking. The aim of the present study was to examine the GH secretion to high intensity interval exercise. MethodsSeventeen children (12.4 ± 2.6 years) with impaired growth rate performed high-intensity interval exercise test (HIIE) that included 10 intervals of 15 s all out pedaling against resistance determined by age, sex and weight on a cycle ergometer with 1-min active rest between each interval. Power output measurements were collected during the test. Blood samples were collected before, immediately after, 30, 45, and 60min after the beginning of the exercise test. GH response was compered to pharmacological provocation test (clonidine or glucagon). ResultsHIIE led to a significant increase in GH levels (p < 0.001), with high correlation to GH response following pharmacological stimulation (r = 0.82, r = 0.80 for clonidine and glucagon respectively, p < 0.001) A significant correlation was found between mean peak power to body weight and the GH response (r = 0.50, p = 0.04). 83% of the participants who reached peak power > 10 watts/kg had normal GH secretion. ConclusionsHIIE is a brief and individualized exercise protocol that may be used as a physiological provocation test for GH secretion. There might be a minimum of anaerobic power needed to induce adequate GH response during HIIE.

High Anxiety Levels and Growth Hormone Secretion in Children with Short Stature

Growth hormone (GH) provocation test, which includes repeated blood measurements following pharmacological stimuli, may be stressful for the children and their family. Thirty-three short stature children with impaired growth rate were studied during GH provocation tests to determine if the test is associated with increased anxiety and if increased anxiety affects the test results.

P1.03: Intravenous glucose nocturnal infusion reduces growth hormone secretion in children on total parenteral nutrition

Introduction: Most children with intestinal failure (IF) benefit from home parenteral nutrition (HPN). It allows a familial life with normal children activities such as going to school, sports, and being at home. In order to do so, PN is provided with cyclic infusion at night. Children with IF on HPN should have normal growth. However, some children grow under their genetic target height and present with decreased height velocity. Methods: We report the case of two children on HPN who presented with decreased height velocity while their weight gain was normal. After ruling out usual etiology (insufficient protein intake, acidosis, sodium deficiency, IFALD…), growth hormone (GH) deficiency was considered. Extensive testings were performed such as IgF1 levels, GH secretion stimulation test and nocturnal GH secretion. PN dependency was assessed using the PN/REE index (parenteral nutrition non-protein energy intake divided by resting energy expenditure calculated using Schofield equation, expressed in percentage). Results: These two children needed extremely high PN caloric intake to achieve a normal weight gain with a PN dependency index of 163% and 150%. Table 1 shows their clinical characteristics. Table 2 shows the results of the biological testings. These two children showed a normal GH peak under stimulation, but a low nocturnal GH secretion meaning they were able to produce GH under stimulation, but their nocturnal physiological secretion was inhibited. Their mean glycemia during PN perfusion was high compared to fasting glycemia which should normally be observed at night in children. Hyperglycemia is a well known inhibitor of GH secretion. Conclusion: Children with very high PN dependency are at risk of developing reduced height. In some children, GH secretion seems to be inhibited by nocturnal high glucose infusion. A longer PN infusion time can be proposed and/or a decrease in glucose intake with an increase in lipid intake. Also, growth hormone supplementation might be discussed and should be evaluated in this setting.

Growth hormone secretion in children treated for medulloblastoma

Growth hormone secretion in children treated for medulloblastoma

The timing of administration of exogenous glucocorticoid affects 24 hour growth hormone secretion in children

Exogenous glucocorticoids may suppress linear growth by affecting the diurnal secretory rhythm of GH. ObjectiveTo assess whether the timing of exogenous glucocorticoid administration affects GH secretion in children. DesignFour girls and four boys aged 10.6 to 15.8 (mean 13.2) years with normal weight and height and pubertal stages I–IV were studied in an open randomized 2-period cross-over trial, with a 1-day un-in, and two 4-day periods of 5mg prednisolone in the morning or in the evening, respectively, separated by a 3-week washout period. At run-in and on the last day of each treatment period serum was collected every 20min for 24h for assessment of GH. Secondary analyses were serum levels of IGF-I and IGFBP-3 (measured every 8h), and IGFBP-1, insulin, and collagen markers PICP, PINP, ICTP and PIIINP (measured every 2h). ResultsEvening prednisolone suppressed 24hour GH secretion (P=0.016), overnight GH secretion (P=0.023) and IGF-I (P=0.024) when compared to morning prednisolone, but not when compared to run-in. Evening prednisolone also increased nocturnal insulin levels as compared to run-in (P=0.010). Irrespective of time of day, prednisolone increased serum collagen markers PICP, PIINP, ICTP and PINP (all P<0.05). ConclusionsShort-term prednisolone 5mg administered in the morning may alleviate nocturnal GH suppression as compared to evening administration. In analogy, growth rates are less affected by morning as compared to evening administration of exogenous glucocorticoids. In contrast, collagen markers and metabolic indices were not affected by the timing of prednisolone administration.

Serum α-klotho levels are not informative for the evaluation of growth hormone secretion in short children.

α-Klotho is a transmembrane protein that can be cleaved and act as a circulating hormone (s-klotho). s-Klotho serum levels seem to reflect growth hormone (GH) secretory status. We investigated the role of s-klotho as a reliable marker of GH secretion in short children and the factors influencing its secretion. We enrolled 40 short Egyptian children (20 GH deficiency [GHD] and 20 idiopathic short stature [ISS]). They underwent a pegvisomant-primed insulin tolerance test (ITT) and were accordingly reclassified as 16 GHD and 24 ISS. The samples obtained before and 3 days after pegvisomant administration, prior to the ITT, were used for assaying insulin-like growth factor (IGF)-I and s-klotho. IGF-I and s-klotho serum levels were not significantly different (p=0.059 and p=0.212, respectively) between GHD and ISS. After pegvisomant, a significant reduction in IGF-I and s-klotho levels was found in both groups. s-Klotho significantly correlated only with IGF-I levels in both groups. s-Klotho mainly reflects the IGF-I status and cannot be considered a reliable biomarker for GH secretion in children.

A pilot study of the effects of niacin administration on free fatty acid and growth hormone concentrations in children with obesity

Children with obesity have low spontaneous growth hormone (GH) secretion. High circulating free fatty acid (FFA) concentration is believed to inhibit GH secretion in those with obesity. In adults, lipolytic inhibition with niacin lowers FFA and increases GH, but there are no prior studies in children with obesity. The objective of the study was to determine the dose and frequency of niacin administration required to lower FFA and stimulate GH in children with obesity. Dose-finding study of nondiabetic children ages 6-12 years with body mass index (BMI) ≥ 95th percentile given niacin 250 mg q2h × 3 doses (n = 2), 500 mg q2h × 3 doses (n = 5) or 500 mg q1h × 4 doses (n = 5). Eight boys and four girls (age 9.7 ± 1.8 years; BMI 26.4 ± 3.1 kg m-2 ; BMIz 2.2 ± .25) were studied. Percentage of serum FFA values that were below 0.2 mEq L-1 . GH, insulin and glucose were also measured serially. FFA decreased as the dose and frequency of niacin increased (p = .01). Niacin 500 mg q1h 4 doses suppressed FFA < 0.2 mEq L-1 and significantly increased GH (p = .04). Adverse effects were flushing/warmth (100%), tingling (60%) and GI complaints (20-40%). Niacin 500 mg q1h significantly lowered serum FFA and increased GH. These pilot data suggest that high FFA is an important suppressor of GH secretion in children with obesity.

The Wingate anaerobic test cannot be used for the evaluation of growth hormone secretion in children with short stature

PurposeTo assess the growth hormone (GH) response to the Wingate anaerobic test (WAnT) among children with short stature and suspected GH deficiency. We hypothesized that the GH response to the WAnT would be similar to the GH response to a commonly used pharmacologic provocation test. MethodsTen children (6 males and 4 females, age range 9.0–14.9 years) participated in the study. Each participant performed 2 tests: a standard all-out WAnT, cycling for 30 s against constant resistance, and a standardized pharmacologic test (clonidine or glucagon). Blood samples for GH were collected before and 10, 30, 45, and 60 min after the beginning of exercise. In addition, we collected pre- and post-exercise blood lactate levels. ResultsThere was a significant increase in GH levels after the WAnT, yet in 9 of 10 participants, this increase was below the threshold for GH sufficiency. Peak GH after the WAnT was significantly lower compared to the pharmacologic GH provocation tests (with 9 of 10 demonstrating GH-sufficient response). ConclusionThe traditional WAnT cannot be used as a GH provocation test. Further research is needed to develop anaerobic exercise protocols sufficient to promote GH secretion.

Growth hormone secretion and its effect on height in pediatric patients with different genotypes of Prader–Willi syndrome

There have been multiple reports regarding the growth hormone (GH) secretion in patients with Prader-Willi syndrome (PWS). However, none have compared GH secretion in children with deletion group to those with maternal uniparental disomy (UPD). We evaluated the GH secretion in pediatric patients with PWS. Seventy-six patients with a deletion (n = 55) or UPD (n = 21) were studied. The secretion of GH by insulin stimulation in the patients with UPD (3.6 ± 2.2 ng/ml) was significantly lower than those with deletions (peak GH level: 11.1 ± 8.6 ng/ml; P = 0.0013). We also compared the response to GH replacement therapy. Yearly improvements in height standard deviation score (SDS) were similar in the two groups (first year SDS: 0.47 ± 0.47, deletion; 0.68 ± 0.26, UPD; P = 0.14).

Effect of long term glucocorticoid treatment on human growth hormone secretion in children and adolescents and the safety and effectiveness of recombinant human growth hormone treatment.

Long term glucocorticoid (prednisolone) treatment on human growth hormone (hGH) secretion in children and adolescents and to investigate the effectiveness and safety of the recombinant human growth hormone (rhGH) treatment. Twelve patients (age: 10.4∓1.2 years) who were treated in Peking Union Medical College Hospital from September 1999 to November 2009 were enrolled in this study. All of them had taken prednisolone with a dose of 0.5∓2.0 mg/(kg.d) for 6~18 months. Two different hGH stimulating tests was done and their growth and development was evaluated at regular intervals. Seven patients were given rhGH with a dose of 0.1 U/(kg.d) for 6~12 months to improve their growth and development after half a year of prednisolone withdrawal when their disease conditions were improved. The growth speed of these 12 children decreased significantly during prednisolone treatment compared with before prednisolone treatment (1.2∓0.3cm/year vs.3.7∓1.2 cm/year,P12 months than those with a 6~12 months course (P0.05). The growth speed of seven children who received rhGH therapy for half a year were increased from 2.2∓0.1cm/year to 7.8∓0.5cm/year (P<0.05), and then to 6.9∓0.4cm/year one year later. The long-term glucocorticoid treatment can decrease the hGH secretion, and thus leads to short stature and agenesis. However, the rhGH replacement can safely and effectively improve growth and development in these children after their primary diseases are improved and glucocorticoids are withdrawn.

Puberty, statural growth, and growth hormone release in children with cerebral palsy.

Children with cerebral palsy (CP) are smaller than normally growing children.. The association between the growth hormone (GH) axis and growth in children with CP during puberty is unknown. We compared growth and markers of the GH axis in pre-pubertal and pubertal children with moderate to severe CP and without CP over a three-year period. Twenty children with CP, ages 6-18, Gross Motor Function Classification System levels III-V, were compared to a group of sixty-three normally growing children of similar age. Anthropometry, Tanner stage, bone age, and laboratory analyses were performed every six months for three years. Laboratory values included spontaneous overnight GH release, fasting IGF-1 and IGFBP-3. Repeated measures models were used to evaluate interactions among Tanner stage and group (children with CP vs. reference children), taking into account gender, age, and nutritional status. Children with CP grew more slowly than those without CP at all Tanner stages (p<0.01). Patterns of IGF-1 and GH secretion in children with CP were similar to those of the reference group; however, the concentrations of IGF-1 (p<0.01) and GH (p<0.01) were lower in girls with CP, with a similar trend for boys (p=0.10 and 0.14, respectively). Diminished circulating IGF-1 and GH concentrations may explain the differences in growth between the two groups.

Exercise Provocation Test for Growth Hormone Secretion: Methodologic Considerations

The diagnosis of Growth Hormone (GH) deficiency in children with short stature is complex, and in certain cases, might be very difficult. Most of the provocative tests used to evaluate GH deficiency use pharmacological agents. The artificial nature of the pharmacological tests and the possibility that these tests might not always reflect GH secretion under normal physiological conditions provides the impetus for a more physiologic test. Exercise is one of the important GH releasing physiological stimuli. This review will summarize the current knowledge on the methods for performing laboratory exercise provocation test for GH secretion in children. In addition to recommendations of more standardized exercise protocols and environmental considerations, we will also focus on GH responses to exercise in unique populations such as obese children.

Combined Growth Hormone-Releasing Hormone and Growth Hormone-Releasing Peptide-6 Test for the Evaluation of Growth Hormone Secretion in Children with Growth Hormone Deficiency and Growth Hormone Neurosecretory Dysfunction

Background: The combined growth hormone-releasing hormone and growth hormone-releasing peptide-6 (GHRH + GHRP-6) test is most potent in evaluating GH secretion. Aims: To assess its capability in children with GH deficiency and low spontaneous GH secretion (GH neurosecretory dysfunction). Methods: 35 children with GH <10 µg/l after levo-dopa/clonidine (GHD), 15 with normal provocative tests but abnormal 24-hour spontaneous GH secretion (GHND), and 20 controls (C) were given 1 µg/kg of GHRH and GHRP-6 i.v. and GH (µg/l) was measured at –15, 0, 5, 10, 15, 30, 45 and 60 min. Results: Six were nonresponders to the combined test, with significantly lower peak GH 20.7 (7.8–31.8) than C and the rest of the patients (responders). Peak GH was similar between prepubertal (PP) controls 167 ± 88, GHD 202 ± 110 and GHND 155 ± 83. Pubertal (P) controls had higher peak GH 328 ± 149 than P-GHD 203 ± 105 and P-GHND 186 ± 105. While P-C had higher peak GH than PP-C, PP and P children had similar responses within the GHD and GHND groups. Conclusions: The GHRH + GHRP-6 test detects children with severe GH insufficiency. Patients with GHD respond similarly to those with GHND, indicating a possible hypothalamic GH neuroregulatory dysfunction in GHD. Responders to the combined test may be eligible for treatment with a synthetic GH secretagogue.

Spontaneous Growth Hormone (GH) Secretion Is Not Directly Affected by Ghrelin in Either Short Normal Prepubertal Children or Children with GH Neurosecretory Dysfunction

Ghrelin, a specific endogenous ligand for the GH secretagogue receptor, stimulates GH secretion in humans when given in pharmacological amounts. Under physiological conditions, however, it is controversial whether ghrelin affects GH secretion and vice versa. No studies have reported on the relationship between daily ghrelin and GH secretion in children. Therefore, plasma ghrelin and GH concentrations over a 24-h period were studied in 10 prepubertal short normal children (five females and five males) to determine the potential relationship between the secretion of these two hormones. Furthermore, five prepubertal patients (two females and three males) with GH neurosecretory dysfunction (GHNSD) were studied in the same way to assess potential alterations in ghrelin secretion in a condition associated with distinct GH changes. No gender difference in ghrelin spontaneous secretion was detected in either short normal children or GHNSD patients, and in both male and female subjects, ghrelin was secreted in a pulsatile and circadian fashion, with a nocturnal surge. Twenty-four-hour secretion and daytime ghrelin secretion of short normal children were similar to those in GHNSD patients, whereas nighttime hormone secretion in the latter group was significantly greater than that in short normal children. The cross-correlation of 24-h ghrelin and GH levels revealed significant positive and negative correlations, which were similar in the two groups examined. The positive one, with GH leading ghrelin, might reflect a somatostatin (SMS)-mediated inhibitory effect on both GH and ghrelin secretion (low SMS levels are followed by high GH and ghrelin levels, and vice versa). The negative correlation, with ghrelin leading GH, might again reflect the positive effect of ghrelin on SMS, as shown in both animal and human studies. In conclusion, the results of the present study indicate that ghrelin secretion in prepubertal children is pulsatile and is not sexually dimorphic. Although the parallelism of ghrelin and GH dynamics hints at the potential relevance of endogenous ghrelin as a promoter of GH release, our data do not support this hypothesis. We suggest that the interactions of ghrelin and GH are the result of SMS action. SMS inhibits GH secretion not only by a direct effect on the pituitary and by inhibiting hypothalamic GHRH, but also through the suppression of ghrelin release.

Standard and low‐dose IGF‐1 generation tests and spontaneous growth hormone secretion in children with idiopathic short stature

Standard and low‐dose IGF‐1 generation tests and spontaneous growth hormone secretion in children with idiopathic short stature

Standard and low‐dose IGF‐I generation tests and spontaneous growth hormone secretion in children with idiopathic short stature

Abnormalities in the GH-IGF-I axis, consistent with GH insensitivity (GHI), have been reported in some patients with idiopathic short stature (ISS). The standard IGF-I generation test (IGFGT) has not demonstrated mild GHI in subjects with ISS. The aim of this study was to investigate the GH-IGF-I axis in ISS by performing standard and novel low-dose IGFGTs together with determination of spontaneous GH secretion. Twenty-one (17 male) prepubertal children with ISS, mean age 8.3 years (4.5-12.2), mean height -3.48 SD (-5.40 to -1.79), mean peak GH to provocation with glucagon/clonidine 32.3 mU/l (14.1-66.0) were studied. Serum IGF-I and IGFBP-3 levels were measured during standard (GH 0.033 mg/kg/day x 4) and low (GH 0.011 mg/kg/day x 4) dose IGFGTs at 0, 12, 36 and 84 h. The low-dose IGFGT was performed in seven naive GH-deficient patients (4 male), mean age 8.5 years (range 4.1-11.1). Determination of spontaneous 24-h GH secretion was performed in the 21 ISS patients. Basal IGF-I and IGFBP-3 standard deviation scores (SDS) in ISS patients were -1.39 (-2.4-1.16) and -0.45 (-1.13-0.38), respectively, IGF-I being lower than IGFBP-3 (P < 0.0001). IGF-I increased in the standard IGFGT at 12 h (P < 0.005), 36 h (P < 0.001) and 84 h (P < 0.001); maximal increment 1.54 (-0.32-3.48), and in the low-dose test at 12 h (P < 0.005), 36 h (P < 0.001) and 84 h (P < 0.005); maximal increment 0.53 (0.08 to -1.23). IGFBP-3 SDS increased in the standard IGFGT at 36 h (P < 0.01) and 84 h (P < 0.001); maximal increment 0.72 (-0.44-1.96), and in the low-dose test at 84 h (P < 0.005); maximal increment 0.33 (-0.08-0.87). Five/19 patients with an IGF-I response > 2 x coefficient of variation (CV) of assay in the standard test failed to respond in the low-dose test, suggestive of mild GHI. In GH-deficient patients, IGF-I increased at each time point (P < 0.05) and IGFBP-3 at 36 h (P < 0.05). Mean GH secretion, expressed in SDS, compared with 66 normal stature controls was: basal GH -0.48 (-0.84-0.93), height of GH peaks compared with zero -0.36 (-1.26-1.51) (both P < 0.05), total GH secretion -0.76 (-1.22-0.42), total GH secretion above baseline -0.67 (-1.21-0.94) (both P < 0.01). In children with ISS, basal IGF-I and IGFBP-3 SDS values were below the mean, IGF-I showing a greater response in both IGFGTs. In the standard IGFGT, the IGF-I increase at 36 h was equal to that at 84 h. The low-dose IGFGT, in combination with the standard test, may identify patients with mild GHI.

Spontaneous nocturnal growth hormone secretion in children after medulloblastoma therapy.

Spontaneous nocturnal growth hormone secretion in children after medulloblastoma therapy.

Neuroregulation of growth hormone during exercise in children.

Physical exercise is an important physiological stimulus to growth hormone (GH) release in man. Many neurotransmitters are involved in GH regulation. We studied the effect of the cholinergic pathway on GH secretion induced by physical exercise. Particularly, we studied the effect of a cholinergic muscarinic agonist on GH-induced physical exercise, both in children and adults. Moreover, we investigated the refractoriness of GH secretion after a second physical exercise stimulus. Three different protocols were performed: 1) GH response to physical exercise in children and adults; 2) effect of pyridostigmine on exercise-induced GH secretion in children and adults; 3) GH response to two consecutive exercises in children and adults. Our data show that in children GH peak after physical exercise is higher than in adults. Pyridostigmine enhances GH release in children and in adults. Exercise stimulus was able to release GH in the second test only in children, while the refractory phase did not permit a new GH release in adults. The shift to a modality of neural control of GH secretion peculiar of adults is likely due to neuroregulatory mechanisms which may be partly dependent on long-term variation in hormonal milieu.

Growth hormone secretion in children and adolescents at high risk for major depressive disorder.

Decreased growth hormone (GH) response to pharmacologic stimulation has been found in children and adolescents during an episode of major depressive disorder and after recovery. In this study, we sought to determine whether GH secretion is similarly altered in children and adolescents who had never experienced depression but were at high risk of developing depression. Subjects were 8 through 16 years of age and selected for high- and low-risk status according to familial loading for mood disorders. Sixty-four high-risk and 55 low-risk healthy subjects participated in the study, which assessed the following GH measures: (1) GH before growth hormone-releasing hormone (GHRH) infusion, every 15 minutes for 30 minutes; (2) GH response after intravenous infusion of GHRH (0.1 microg/kg), every 15 minutes for 90 minutes; and (3) nocturnal GH every 20 minutes from 9 PM until morning awakening. After stimulation with GHRH, the high-risk subjects secreted significantly less GH compared with the low-risk healthy controls (effect sizes for mean and peak GH, 0.52 [P =.007] and 0.40 [P =.04], respectively). In contrast, there were no between-group differences in the pre-GHRH and nocturnal GH secretion levels. Exposure to recent stressors was not associated with GH secretion. Taken together with previous evidence of decreased GH after GHRH infusion in acutely depressed and recovered children, these results indicate that the decreased GH response found in high-risk subjects may represent a trait marker for depression in children and adolescents.