help button home button Endocrine Society JCEM JCEM Call for Nominations for EIC
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Journal of Clinical Endocrinology & Metabolism, doi:10.1210/jc.2005-2185
This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
91/5/1929    most recent
Author Manuscript (PDF)
Right arrow Submit a related Letter to the Editor
Right arrow Purchase Article
Right arrow View Shopping Cart
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Bellone, S.
Right arrow Articles by Bona, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Bellone, S.
Right arrow Articles by Bona, G.
Related Collections
Right arrow Metabolism
Right arrow Neuroendocrinology and Pituitary
Right arrow Pediatric Endocrinology
The Journal of Clinical Endocrinology & Metabolism Vol. 91, No. 5 1929-1933
Copyright © 2006 by The Endocrine Society

Ghrelin Secretion in Preterm Neonates Progressively Increases and Is Refractory to the Inhibitory Effect of Food Intake

S. Bellone, R. Baldelli, G. Radetti, A. Rapa, D. Vivenza, A. Petri, S. Savastio, M. Zaffaroni, F. Broglio, E. Ghigo and G. Bona

Division of Pediatrics (S.B., R.B., A.R., D.V., A.P., S.S., M.Z., G.B.), Department of Medical Sciences, University of Piemonte Orientale, 28100 Novara, Italy; Division of Endocrinology (F.B., E.G.), Department of Internal Medicine, University of Turin, 10126 Turin, Italy; and Department of Pediatrics (G.R.), Regional Hospital, Bolzano 39100, Italy

Address all correspondence and requests for reprints to: Gianni Bona, M.D., Division of Pediatrics, Department of Medical Sciences, University of Piemonte Orientale "Amedeo Avogadro," Corso Mazzini 18, 28100 Novara, Italy. E-mail: gianni.bona{at}maggioreosp.novara.it.


   Abstract
Top
 Abstract
Introduction
 Subjects and Methods
 Results
 Discussion
 References
 
Context: Ghrelin, a natural GH secretagogue, is mainly characterized by nonendocrine activities such as orexigenic effect and modulation of the endocrine and metabolic response to variations in energy balance. Ghrelin levels have been reported to be negatively associated with insulin secretion, enhanced in anorexia, and reduced in obesity. Ghrelin levels in newborns were shown to be similar to those found in children and adults without any gender-related difference.

Objective: The aim of this study was to evaluate ghrelin variations in preterm newborns as a function of fasting and feeding.

Methods: To this end, in 31 preterm neonates (13 males and 18 females) categorized as appropriate for gestational age, total ghrelin levels were measured in cord blood and then on the fourth day of life before and after meals.

Results: Ghrelin levels in cord blood [(median 25th–75th centile) 184; 122–275 pg/ml] were higher (P < 0.006) than levels measured in the mothers at delivery (167.0; 89–190 pg/ml). In newborns on the fourth day of life, ghrelin levels in fasting conditions (451; 348–649 pg/ml) were higher (P < 0.0004) than those in cord blood. The meal did not at all modify ghrelin levels (476; 302–775 pg/ml), which were unchanged, compared with those in fasting condition. Total ghrelin levels in cord blood were not associated with weight and length; conversely, on the fourth day of life ghrelin levels in newborns were negatively correlated to birth weight as well as the present weight (P = 0.05, r = –0.4). Ghrelin levels were independent of gender, type of delivery, and the kind of feeding regimen.

Conclusions: The secretion of total ghrelin increases from delivery to the fourth day of life when it is refractory to the inhibitory effect of food intake, but it is negatively correlated to body weight.


   Introduction
Top
 Abstract
 Introduction
Subjects and Methods
 Results
 Discussion
 References
 
GHRELIN IS A 28-amino-acid peptide predominantly produced by the stomach that has been discovered as a natural ligand of the orphan GH secretagogue receptor (GHS-R) type 1a and is supposed to play a major role in the control of somatotroph function (1). More recently, ghrelin has been considered as a major new orexigenic factor that, coupled with leptin, is likely to signal the metabolic balance and manage the neuroendocrine and metabolic response to starvation (1).

Circulating ghrelin levels are negatively associated with body mass index; ghrelin secretion is increased in anorexia and cachexia, reduced in obesity, and normalized by recovery of ideal body weight (1, 2). A peculiar exception to the negative association between body mass and ghrelin secretion is Prader-Willi syndrome in which obesity is surprisingly associated with absolute or relative ghrelin hypersecretion (3, 4).

In humans, circulating ghrelin levels are increased by energy restriction and decreased by food intake (2, 5), indicating that the regulation of ghrelin secretion is mostly metabolic. Ghrelin secretion is decreased by an iv or oral glucose load as well as during a euglycemic hyperinsulinemic clamp and even after insulin-induced hypoglycemia (6, 7, 8). The inhibitory influence of overexposure to insulin on ghrelin secretion agrees with the strong negative association between ghrelin and insulin levels that had been predicted by the negative correlation between ghrelin levels and body mass index (9). Whether insulin and glucose per se play a direct inhibitory role on ghrelin secretion (10, 11) as well as the influence, if any, of amino acids and lipids (12, 13, 14) is, however, still unclear.

In humans ghrelin secretion undergoes marked variations throughout the day with peaks that anticipate food intake, suggesting that the latter is triggered by ghrelin discharge (15, 16); although these findings have not been confirmed by others (17), there is agreement that morning ghrelin levels positively correlate with 24-h ghrelin secretion (16). On the other hand, whether ghrelin secretion is age and/or gender dependent is still a matter of debate (2). In a previous study, we found that total ghrelin levels were unchanged from birth to young adulthood (18).

Ghrelin is present in human fetal circulation from 20 wk to term (19). Regarding newborns, it has been demonstrated that ghrelin levels in small for gestational age (SGA) subjects are higher than in adequate for gestational age (AGA) subjects (19, 20, 21). Moreover, lower cord ghrelin levels have been found to be associated with slower weight gain from birth to 3 months of age (22); the clinical consequences, if any, of this picture of ghrelin secretion are unclear. In fact, neither the ghrelin nor the GHS-R1a knockout mice are anorectic dwarfs (23, 24); this evidence, however, does not definitely rule out a role of ghrelin in the control of somatotroph secretion, energy balance, and metabolism.

To further clarify the pattern of ghrelin secretion as a function of the nutritional status around birth, we evaluated ghrelin secretion in the first day of life as a function of fasting and fed state in newborns adequate for gestational age.


   Subjects and Methods
Top
 Abstract
 Introduction
 Subjects and Methods
Results
 Discussion
 References
 
We studied 31 neonates (13 males and 18 females) categorized as AGA, born preterm by cesarean section for maternal indications (15 neonates) or spontaneous delivery (16 neonates): gestational age 33.3 ± 1.7 wk (range 31–35 wk), weight 1959 ± 393 g, length 44.2 ± 2.5 cm. AGA was defined as a birth weight from 10th to 90th percentile for gestational age (25). None of the babies showed signs of distress at delivery. Birth weight and length were recorded at birth by the attending nurse. The neonates’ weight and meals were monitored during the first 4 d of life. In breast-fed newborns, infants were weighed before and after breast-feeding.

Twelve newborns were completely breast-fed, and 19 newborns were formula fed. Each feed lasted about 20–30 min. Six newborns were fed by nasogastric tube.

Median (25th–75th centile) of total milk intake per day was 14 (9–35) ml on the first day, 56 (35–70) ml for the second day, 96 (64–120) ml on the third day, and 135 (80–200) on the fourth day.

Median (25th–75th centile) of calories per meal on the fourth day was 10.7 (6.6–17.8) kcal.

The content in carbohydrates, lipids, and protein and the energy intake calculated for each meal in the different kinds of milk were statistically similar.

Venous cord blood was drawn immediately after birth. Ghrelin levels were evaluated in different conditions: in cord blood and the mothers at delivery. In the same neonates, ghrelin levels were also measured on the fourth day of life fasting (just before a meal, i.e. about 3 h after the previous meal) and about 60 min after a meal.

The study protocol had been approved by the ethical committee, and informed consent had been obtained from all infants’ parents.

Human ghrelin (picograms per milliliter) was assayed after extraction in reverse-phase C18 columns by a radioimmunometric assay (Phoenix Pharmaceuticals, Inc., Belmont CA) using 125I-labeled bioactive ghrelin as a tracer and a rabbit polyclonal antibody vs. octanoylated and des-octanoylated human ghrelin (sensitivity 30 pg/tube). Based on our data, the intraassay coefficient of variation range was 0.3–10.7%.

Hormonal data are expressed as median and 25th to 75th centiles, anthropometric parameters as mean ± SD. The statistical analysis was performed using Wilcoxon test and Spearman correlation test as appropriate.


   Results
Top
 Abstract
 Introduction
 Subjects and Methods
 Results
Discussion
 References
 
Ghrelin levels in cord blood [(median; 25th–75th centile) 184; 122–275 pg/ml] were higher (P < 0.006) than those measured in the mothers at the delivery (167.0; 89–190 pg/ml) (Fig. 1Go).


Figure 1
View larger version (14K):
[in this window]
[in a new window]
  		FIG. 1. Plasma ghrelin levels in mothers and newborns in cord blood and fasting on the fourth day of life.

 
In newborns on the fourth day of life, ghrelin levels in fasting conditions (451; 348–649 pg/ml) were higher (P < 0.0004) than those in cord blood (Fig. 1Go).

The meal did not modify ghrelin levels (476; 302–775 pg/ml), which were unchanged, compared with those in fasting condition (Fig. 2Go).


Figure 2
View larger version (12K):
[in this window]
[in a new window]
  		FIG. 2. Ghrelin levels on the fourth day of life before and after a meal.

 
Total ghrelin levels in cord blood were not associated with weight and length; they did not correlate with weight, even when data were normalized as a function of gestational age. Conversely, on the fourth day of life, ghrelin levels in newborns negatively correlated to birth weight as well as the present weight (P = 0.05, r = –0.4 for both) (Fig. 3Go).


Figure 3
View larger version (13K):
[in this window]
[in a new window]
  		FIG. 3. Correlation between fasting ghrelin levels and weight on the fourth day of life.

 
Ghrelin levels did not correlate with gestational age.

Ghrelin levels proved to be independent of both gender and type of delivery either at birth or on the fourth day of life (Table 1Go).


View this table:
[in this window]
[in a new window]
  		TABLE 1. Ghrelin levels at each time point in males and females and neonates born by vaginal or cesarean delivery

 
Ghrelin levels did not vary between breast- and formula-fed infants.

Cord ghrelin levels positively correlated with ghrelin levels at the fourth day of life (P = 0.005, r = 0.5), whereas they did not correlate with ghrelin levels in mothers.


   Discussion
Top
 Abstract
 Introduction
 Subjects and Methods
 Results
 Discussion
References
 
The results of the present study demonstrate that preterm AGA newborns show an increase in total ghrelin secretion from birth (cord levels) to the fourth day of life, which is not modified by a meal. Ghrelin levels are independent of gender and of type of delivery. Circulating total ghrelin levels display negative association with body weight on the fourth day of life but not at birth when, however, they are higher than those in the mothers.

Ghrelin synthesis and secretion from the placenta have been demonstrated (26). In the fetal rat stomach ghrelin, cell population progressively increases from the 18th day of pregnancy, and ghrelin cell number has been found to be positively associated with stomach growth (27). In humans, ghrelin has been demonstrated in fetal circulation from 20 wk to term (19). That these ghrelin levels are produced by the fetus is indicated by the lack of difference between arterial and venous concentration as well as by evidence that ghrelin is almost absent in the placenta during the third trimester (19).

Total ghrelin levels in cord blood at birth have been evaluated both in AGA or SGA newborns (20, 21, 22, 28, 29, 30, 31). Our present data agree with some (22, 28, 29, 31) but not other (20, 21, 31) previous studies showing that circulating total ghrelin levels in cord blood of AGA newborns are independent of gender, body weight, and type of delivery. This is in agreement also with our previous findings in considerable number of newborns in whom ghrelin levels were independent of the two types of delivery (32). Indeed, circulating total ghrelin levels have generally been demonstrated to be higher in SGA than AGA newborns (20, 21, 22, 29, 33). Concerning the correlation between ghrelin and GH/IGF-I axis, no correlation has been reported so often (28, 29, 30); in some studies a negative association between ghrelin and IGF-I or IGF binding protien-3 has been reported (21). These findings agree with the opinion of many authors who believe that ghrelin and somatotroph function are unlikely to be linked by a functional relationship (5). The same concept is likely to apply also to the relationship between ghrelin and leptin; despite the fact that both play relevant actions in the control of appetite and energy expenditure (1, 2), these hormones do not seem linked by direct functional feedback (33).

In the present study as well as two other studies (21, 29), progressive increase in circulating total ghrelin levels in the days after birth has been demonstrated. Moreover, our present study first demonstrates that feeding does not exert its well-known inhibitory effect on circulating total ghrelin levels. It had already been demonstrated that food intake inhibits morning ghrelin secretion in adults but not prepubertal children (34, 35). This ghrelin refractoriness to food intake from birth to childhood would therefore suggest that this hormone is playing a role as an anabolic drive in the phase of life of growth and development. However, it has to be considered that in infants as well as children, ghrelin secretion is sensitive to the inhibitory effect of glucose load despite its refractoriness to feeding (36, 37).

On the other hand, it has to be considered that the first days of life are characterized by physiological weight decrease that reaches a nadir on the fourth day (25). This weight decrease would play a role in stimulating ghrelin secretion and would also account for the refractoriness to the inhibitory effect of feeding, as has been observed also in anorexia nervosa (38). In fact, we, as well as other authors, found that soon after birth and namely on the fourth day of life, circulating total ghrelin levels display inverse association with anthropometric variables, including body weight (22, 29). Furthermore, it has to be considered that in newborns the control of growth is different from that in later life and is related to the immaturity of the neuroendocrine system, in particular in our population consisting of preterm newborns. According to this picture, it has been demonstrated in preterm newborns that circulating concentrations of leptin and free T4 rapidly decrease after birth. This pattern could be a physiological advantage to newborns by limiting body energy expenditure and conserving nutritional reserves for growth and development (39). These data have to be confirmed in a group of full-term newborns.

Furthermore, it has to be taken into consideration that in our study, as well as in others performed in neonates, only total ghrelin levels were measured. This is a limitation in the comprehension of ghrelin’s role in growth and metabolism. In fact, it has been demonstrated that ghrelin circulates in blood in the acylated form that binds GHS-R1a receptors and possesses endocrine activity, and the nonacylated form, which is present in human serum in greater quantities than the acylated one and is able to exert some nonendocrine affects, is devoid of any endocrine activity but exerts some nonendocrine actions including metabolic, cardiovascular, and antiproliferative effects.

In conclusion, the secretion of total ghrelin increases from delivery to the fourth day of life when it is refractory to the inhibitory effect of food intake. This pattern of ghrelin secretion would be focused to represent an anabolic drive in newborns.


   Footnotes
 
All authors have nothing to declare.

First Published Online March 7, 2006

Abbreviations: AGA, Adequate for gestational age; GHS-R, GH secretagogue receptor; SGA, small for gestational age.

Received October 3, 2005.

Accepted February 27, 2006.


   References
Top
 Abstract
 Introduction
 Subjects and Methods
 Results
 Discussion
 References
 

  1. Van der Lely AJ, Tschop M, Heiman ML, Ghigo E 2004 Biological, physiological, pathophysiological, and pharmacological aspects of ghrelin. Endocr Rev 25:426–457[Abstract/Free Full Text]
  2. Korbonits M, Goldstone AP, Gueorguiev M, Grossman AB 2004 Ghrelin—a hormone with multiple functions. Front Neuroendocrinol 25:27–68[CrossRef][Medline]
  3. DelParigi A, Tschop M, Heiman ML, Salbe AD, Vozarova B, Sell SM, Bunt JC, Tataranni PA 2002 High circulating ghrelin: a potential cause for hyperphagia and obesity in Prader-Willi syndrome. J Clin Endocrinol Metab 87:5461–5464[Abstract/Free Full Text]
  4. Goldstone AP, Thomas EL, Brynes AE, Castroman G, Edwards R, Ghatei MA, Frost G, Holland AJ, Grossman AB, Korbonits M, Bloom SR, Bell JD 2004 Elevated fasting plasma ghrelin in Prader-Willi syndrome adults is not solely explained by their reduced visceral adiposity and insulin resistance. J Clin Endocrinol Metab 89:1718–1726[Abstract/Free Full Text]
  5. Ghigo E, Broglio F, Arvat E, Maccario M, Papotti M, Muccioli G 2005 Ghrelin: more than a natural GH secretagogue and/or an orexigenic factor. Clin Endocrinol (Oxf) 62:1–17[CrossRef][Medline]
  6. McCowen KC, Maykel JA, Bistrian BR, Ling PR 2002 Circulating ghrelin concentrations are lowered by intravenous glucose or hyperinsulinemic euglycemic conditions in rodents. J Endocrinol 175:R7–R11
  7. Nakagawa E, Nagaya N, Okumura H, Enomoto M, Oya H, Ono F, Hosoda H, Kojima M, Kangawa K 2002 Hyperglycaemia suppresses the secretion of ghrelin, a novel growth-hormone-releasing peptide: responses to the intravenous and oral administration of glucose. Clin Sci 103:325–328[Medline]
  8. Broglio F, Gottero C, Prodam F, Destefanis S, Gauna C, Me E, Riganti F, Vivenza D, Rapa A, Martina V, Arvat E, Bona G, van der Lely AJ, Ghigo E 2004 Ghrelin secretion is inhibited by glucose load and insulin-induced hypoglycaemia but unaffected by glucagon and arginine in humans. Clin Endocrinol (Oxf) 61:503–509[CrossRef][Medline]
  9. Shiiya T, Nakazato M, Mizuta M, Date Y, Mondal MS, Tanaka M, Nozoe S, Hosoda H, Kangawa K, Matsukura S 2002 Plasma ghrelin levels in lean and obese humans and the effect of glucose on ghrelin secretion. J Clin Endocrinol Metab 87:240–244[Abstract/Free Full Text]
  10. Caixas A, Bashore C, Nash W, Pi-Sunyer F, Laferrere B 2002 Insulin, unlike food intake, does not suppress ghrelin in human subjects. J Clin Endocrinol Metab 87:1902
  11. Schaller G, Schmidt A, Pleiner J, Woloszczuk W, Wolzt M, Luger A 2003 Plasma ghrelin concentrations are not regulated by glucose or insulin: a double-blind, placebo-controlled crossover clamp study. Diabetes 52:16–20[Abstract/Free Full Text]
  12. Lee HM, Wang G, Englander EW, Kojima M, Greeley Jr GH 2002 Ghrelin, a new gastrointestinal endocrine peptide that stimulates insulin secretion: enteric distribution, ontogeny, influence of endocrine, and dietary manipulations. Endocrinology 143:185–190[Abstract/Free Full Text]
  13. Erdmann J, Lippl F, Schusdziarra V 2003 Differential effect of protein and fat on plasma ghrelin levels in man. Regul Pept 116:101–107[CrossRef][Medline]
  14. Groschl M, Knerr I, Topf HG, Schmid P, Rascher W, Rauh M 2003 Endocrine responses to the oral ingestion of a physiological dose of essential amino acids in humans. J Endocrinol 179:237–244[Abstract]
  15. Tschop M, Wawarta R, Riepl RL, Friedrich S, Bidlingmaier M, Landgraf R, Folwaczny C 2001 Post-prandial decrease of circulating human ghrelin levels. J Endocrinol Invest 24:RC19–RC21
  16. Cummings DE, Purnell JQ, Frayo RS, Schmidova K, Wisse BE, Weigle DS 2001 A preprandial rise in plasma ghrelin levels suggests a role in meal initiation in humans. Diabetes 50:1714–1719[Abstract/Free Full Text]
  17. Barkan AL, Dimaraki EV, Jessup SK, Symons KV, Ermolenko M, Jaffe CA 2003 Ghrelin secretion in humans is sexually dimorphic, suppressed by somatostatin, and not affected by the ambient growth hormone levels. J Clin Endocrinol Metab 88:2180–2184[Abstract/Free Full Text]
  18. Bellone S, Rapa A, Vivenza D, Castellino N, Petri A, Bellone J, Me E, Broglio F, Prodam F, Ghigo E, Bona G 2002 Circulating ghrelin levels as function of gender, pubertal status and adiposity in childhood. J Endocrinol Invest 25:RC13–RC15
  19. Cortelazzi D, Cappiello V, Morpurgo PS, Ronzoni S, Nobile De Santis MS, Cetin I, Beck-Peccoz P, Spada A 2003 Circulating levels of ghrelin in human fetuses. Eur J Endocrinol 149:111–116[Abstract]
  20. Farquhar J, Heiman M, Wong AC, Wach R, Chessex P, Chanoine JP 2003 Elevated umbilical cord ghrelin concentrations in small for gestational age neonates. J Clin Endocrinol Metab 88:4324–4327[Abstract/Free Full Text]
  21. Kitamura S, Yokota I, Hosoda H, Kotani Y, Matsuda J, Naito E, Ito M, Kangawa K, Kuroda Y 2003 Ghrelin concentration in cord and neonatal blood: relation to fetal growth and energy balance. J Clin Endocrinol Metab 88:5473–5477[Abstract/Free Full Text]
  22. James RJ, Drewett RF, Cheetham TD 2004 Low cord ghrelin levels in term infants are associated with slow weight gain over the first 3 months of life. J Clin Endocrinol Metab 89:3847–3850[Abstract/Free Full Text]
  23. Sun Y, Ahmed S, Smith RG 2003 Deletion of ghrelin impairs neither growth nor appetite. Mol Cell Biol 23:7973–7981[Abstract/Free Full Text]
  24. Sun Y, Wang P, Zheng H, Smith RG 2004 Ghrelin stimulation of growth hormone release and appetite is mediated through the growth hormone secretagogue receptor. Proc Natl Acad Sci USA 101:4679–4684[Abstract/Free Full Text]
  25. Lubchenco LO, Koops BL 1987 Assessment of weight and gestational age. In: Avery GB, ed. Neonatology. Philadelphia: JB Lippincott Co.; 235–257
  26. Gualillo O, Caminos J, Blanco M, Garcia-Caballero T, Kojima M, Kangawa K, Dieguez C, Casanueva F 2001 Ghrelin, a novel placental-derived hormone. Endocrinology 142:788–794[Abstract/Free Full Text]
  27. Hayashida T, Nakahara K, Mondal MS, Date Y, Nakazato M, Kojima M, Kangawa K, Murakami N 2002 Ghrelin in neonatal rats: distribution in stomach and its possible role. J Endocrinol 173:239–245[Abstract]
  28. Chanoine JP, Yeung LP, Wong AC 2003 Umbilical cord ghrelin concentrations in Asian and Caucasian neonates. Horm Res 60:116–120[CrossRef][Medline]
  29. Soriano-Guillen L, Barrios V, Chowen JA, Sanchez I, Vila S, Quero J, Argente J 2004 Ghrelin levels from fetal life through early adulthood: relationship with endocrine and metabolic and anthropometric measures. J Pediatr 144:30–35[CrossRef][Medline]
  30. Chanoine JP, Yeung LP, Wong AC, Birmingham CL 2002 Immunoreactive ghrelin in human cord blood: relation to anthropometry, leptin, and growth hormone. J Pediatr Gastroenterol Nutr 35:282–286[CrossRef][Medline]
  31. Onal EE, Cinaz P, Atalay Y, Turkyilmaz C, Bideci A, Akturk A, Okumus N, Unal S, Koc E, Ergenekon E 2004 Umbilical cord ghrelin concentrations in small- and appropriate-for-gestational age newborn infants: relationship to anthropometric markers. J Endocrinol 180:267–271[Abstract]
  32. Bellone S, Rapa A, Vivenza D, Vercellotti A, Petri A, Radetti G, Bellone J, Broglio F, Ghigo E, Bona G 2004 Circulating ghrelin levels in the newborn are positively associated with gestational age. Clin Endocrinol (Oxf) 60:613–617[Medline]
  33. Chan JL, Bullen J, Lee JH, Yiannakouris N, Mantzoros CS 2004 Ghrelin levels are not regulated by recombinant leptin administration and/or three days of fasting in healthy subjects. J Clin Endocrinol Metab 89:335–343[Abstract/Free Full Text]
  34. Gottero C, Bellone S, Rapa A, van Koetsveld P, Vivenza D, Prodam F, Benso A, Destefanis S, Gauna C, Bellone J, Hofland L, van der Lely AJ, Bona G, Ghigo E, Broglio F 2003 Standard light breakfast inhibits circulating ghrelin level to the same extent of oral glucose load in humans, despite different impact on glucose and insulin levels. J Endocrinol Invest 26:1203–1207[Medline]
  35. Bellone S, Castellino N, Broglio F, Rapa A, Vivenza D, Radetti G, Bellone J, Gottero C, Ghigo E, Bona G 2004 Ghrelin secretion in childhood is refractory to the inhibitory effect of feeding. J Clin Endocrinol Metab 89:1662–1665[Abstract/Free Full Text]
  36. Iniguez G, Ong K, Pena V, Avila A, Dunger D, Mericq V 2002 Fasting and post-glucose ghrelin levels in SGA infants: relationships with size and weight gain at one year of age. J Clin Endocrinol Metab 87:5830–5833[Abstract]
  37. Soriano-Guillen L, Barrios V, Martos G, Chowen JA, Campos-Barros A, Argente J 2004 Effect of oral glucose administration on ghrelin levels in obese children. Eur J Endocrinol 151:119–121[Abstract]
  38. Nedvidkova J, Krykorkova I, Bartak V, Papezova H, Gold PW, Alesci S, Pacak K 2003 Loss of meal-induced decrease in plasma ghrelin levels in patients with anorexia nervosa. J Clin Endocrinol Metab 88:1678–1682[Abstract]
  39. Ng PC, Lam CW, Lee CH, Wong GW, Fok TF, Chan IH, Ma KC, Wong E 2000 Leptin and metabolic hormones in preterm newborns. Arch Dis Child Fetal Neonatal Ed 83:F198–F202




This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
91/5/1929    most recent
Author Manuscript (PDF)
Right arrow Submit a related Letter to the Editor
Right arrow Purchase Article
Right arrow View Shopping Cart
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Bellone, S.
Right arrow Articles by Bona, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Bellone, S.
Right arrow Articles by Bona, G.
Related Collections
Right arrow Metabolism
Right arrow Neuroendocrinology and Pituitary
Right arrow Pediatric Endocrinology

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Endocrinology Endocrine Reviews J. Clin. End. & Metab.
Molecular Endocrinology Recent Prog. Horm. Res. All Endocrine Journals