Journal of Endocrinological Investigation

, Volume 16, Issue 2, pp 95–98 | Cite as

Galanin infusion partially restores the blunted growth hormone responses to repeated growth hormone releasing hormone stimuli in normal adults

  • Alessandro Sartorio
  • A. Spada
  • A. Conti
  • G. Grugni
  • F. Morabito
  • G. Faglia


In order to understand the role exerted by the endogenous somatostatinergic tone in the blunting of GH responsiveness to repeated GHRH administration, we evaluated GH responses to the second GHRH bolus during a simultaneous infusion of galanin, which has been reported to inhibit the endogenous somatostatin release. Seven normal adults (3M/4F, age range 19–28 yr), admitted to the study after giving informed consent, were tested on three occasions, with a) two consecutive 1 μg/kg iv GHRH boluses administered at 0 min and 120 min, b) one GHRH bolus at 0 min followed by an infusion of 10 μ/kg bw galanin (diluted in 40 ml 0.9% NaCI) between 100 min and 140 min and c) two consecutive GHRH boluses (same dose and temporization of administration of test a) associated with a galanin infusion from 100 min to 140 min. GH responses were evaluated as the net incremental area under the curve (GH nAUC/h); all data were expressed as mean±SE. GH responses to the first GHRH bolus were similar in the three tests (mean GH nAUC, test A 990±80, test B: 1006±112, test C: 1077±80 ng/ml/h). In test A the second GHRH bolus was unable to sustain GH elevated levels (mean GH nAUC: 32±12 ng/ml/h vs first GHRH: 990±80 ng/ml/h, p<0.0001). Similarly, in test B galanin infusion alone was unable to determine a clear GH rise (mean GH nAUC: −25±16 vs first GHRH: 1006±112 ng/ml/h, p<0.0001). In test C, the concomitant galanin infusion enhanced GH responsiveness to the second GHRH bolus (mean GH nAUC: 407±73 ng/ml/h vs GHRH alone: 32±12 ng/ml/h, p<0.005), GH responses being however lower than after the first GHRH administration (p<0.0001). In conclusion, our data show that simultaneous galanin infusion partially restores GH response to the second GHRH bolus in normal adults, thus indicating that the depletion of the intracellular GH pool can not completely account for the reduction of GH responsiveness.


Galanin GH GHRH normals 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Sartorio A., Spada A., Morabito F., Faglia G. Different GH responsiveness to repeated GHRH administration in normal children and adults. J. Endocrinol. Invest. 11: 727, 1988.PubMedCrossRefGoogle Scholar
  2. 2.
    Ghigo E., Goffi S., Mazza E., Arvat E., Procopio M., Bellone J., Muller E.E., Camanni F. Repeated GH-releasing hormone administration unravels different GH secretory patterns in normal adults and children. Acta Endocrinol. (Copenh.) 120: 598, 1989.Google Scholar
  3. 3.
    Sartorio A., Spada A., Arosio M., Conti A., Faglia G., De Nicolao G. Effects of consecutive doses of GHRH on GH secretion. Clin. Endocrinol. (Oxf.) 35: 187, 1991.CrossRefGoogle Scholar
  4. 4.
    Losa M., Bock L., Schopohl J., Stalla G.K., Müller O.A., Von Werder K. Growth hormone releasing factor infusion does not sustain elevated GH levels in normal subjects. Acta Endocrinol. (Copenh.) 107: 462, 1984.Google Scholar
  5. 5.
    Vance M.L., Kaiser D.L., Evans W.S., Thorner M.O., Furlanetto R., Rivier J., Vale W., Perisutti G., Frohman L.A. Evidence for a limited growth hormone (GH)-releasing hormone (GHRH)-releasable quantity of GH: effects of 6-hour infusions of GHRH on GH secretion in normal man. J. Clin. Endocrinol. Metab. 60: 370, 1985.PubMedCrossRefGoogle Scholar
  6. 6.
    Bilezjian L.M., Vale W.W. Chronic exposure of cultured rat anterior pituitary cells to GRF causes partial loss of responsiveness to GRF. Endocrinology 115: 2032, 1984.CrossRefGoogle Scholar
  7. 7.
    Ceda G.P., Hoffman A.R. Growth hormone-releasing factor desensitization in rat anterior pituitary cells in vitro. Endocrinology 116: 1334, 1985.PubMedCrossRefGoogle Scholar
  8. 8.
    Massara F., Ghigo E., Molinatti P., Mazza E., Locatelli V., Muller E.E., Camanni F. Potentiation of cholinergic tone by pyridostigmine bromide reinstates and potentiates the growth hormone responsiveness to intermittent administration of growth hormone-releasing factor in man. Acta Endocrinol. (Copenh.) 113: 12, 1986.Google Scholar
  9. 9.
    Simard J., Lefevre G., Labrie F. Somatostatin prevents the desensitizing action of growth hormone-releasing factor on growth hormone release. Peptides 8: 199, 1987.PubMedCrossRefGoogle Scholar
  10. 10.
    Murakami Y., Kato Y., Koshiyama H., Inoue T., Yanaihara N., Imura H. Galanin stimulates growth hormone (GH) secretion via GH-releasing factor (GRF) in conscious rats. Eur. J. Pharmacol. 136: 415, 1987.PubMedCrossRefGoogle Scholar
  11. 11.
    Ottlecz A., Samson W.K., Mc Cann S.M. Galanin: evidence for a hypothalamic site of action to release growth hormone. Peptides 7: 51, 1986.PubMedCrossRefGoogle Scholar
  12. 12.
    Meister B., Hulting A.L. Influence of coexisting hypothalamic messengers on growth hormone secretion from rat anterior pituitary cells in vitro. Neuroendocrinology 46: 387, 1987.PubMedCrossRefGoogle Scholar
  13. 13.
    Bauer F.E., Ginsberg L., Venetikou M., Mackay D.J., Burrin J.M., Bloom S.R. Growth hormone release in man induced by galanin, a new hypothalamic peptide. Lancet. 2: 192, 1986.PubMedCrossRefGoogle Scholar
  14. 14.
    Davis T.M.E., Burrin J.M., Bloom S.R. Growth hormone (GH) release in response to GH-releasing hormone in man is 3-fold enhanced by galanin. J. Clin. Endocrinol. Metab. 65: 1248, 1987.PubMedCrossRefGoogle Scholar
  15. 15.
    Chatterjee V.K.K., Ball J.A., Proby C., Burrin J.M., Bloom S.R. Galanin abolishes the inhibitory effect of cholinergic blockade on growth hormone-releasing hormone-induced secretion of growth hormone in man. J. Endocrinol. 116: R1–R2, 1987.CrossRefGoogle Scholar
  16. 16.
    Loche S., Vista N., Ghigo E., Vannelli S., Arvat E., Benso L., Corda R., Cella S. G., Muller E.E., Pintor C. Evidence for involvement of endogenous somatostatin in the galanin-induced growth hormone secretion in children. Pediatr. Res. 27: 405, 1990.PubMedCrossRefGoogle Scholar
  17. 17.
    Coiro V., D’Amato L., Borciani E., Rossi G., Cammellini L., Maffei M.C., Pignatti D., Chiodera P. Nicotine from cigarette smoking enhances clonidine-induced increase of serum growth hormone concentrations in man. Br. J. Pharmacol. 18: 802, 1984.CrossRefGoogle Scholar
  18. 18.
    Arvat E., Ghigo E., Nicolosi M., Boffano G.M., Bellone J., Yin-Zhang W., Mazza E., Camanni F. Galanin reinstates the growth hormone response to repeated growth hormone-releasing hormone administration in man. Clin. Endocrinol. (Oxf.) 36: 347, 1992.CrossRefGoogle Scholar
  19. 19.
    Murukami Y., Kato Y., Shimatsu A., Koshiyama H., Hattori N., Yanaihara N., Imura H. Possible mechanisms involved in growth hormone secretion induced by galanin in the rat. Endocrinology 124: 1224, 1989.CrossRefGoogle Scholar
  20. 20.
    Shibasaki T., Hotta M., Masuda A., Imaki T., Obara N., Demura H., Ling N., Shizume K. Plasma growth hormone responses to growth hormone-releasing hormone and insulin-induced hypoglycemia in man. J. Clin. Endocrinol. Metab. 60: 1265, 1985.PubMedCrossRefGoogle Scholar
  21. 21.
    Hülse J.A., Rosenthal S.M., Cuttler L., Kaplan S.L., Grumbach M.M. The effect of pulsatile administration, continuous infusion, and diurnal variation on the growth hormone (GH) response to GH-releasing hormone in normal men. J. Clin. Endocrinol. Metab. 63: 872, 1986.PubMedCrossRefGoogle Scholar
  22. 22.
    Suri D., Hindmarsh P.C., Matthews D.R., Brain C.E., Brook C.G.D. The pituitary gland is capable of responding to two successive doses of growth hormone releasing hormone (GHRH). Clin. Endocrinol. (Oxf.) 34: 17, 1991.CrossRefGoogle Scholar

Copyright information

© Italian Society of Endocrinology (SIE) 1993

Authors and Affiliations

  • Alessandro Sartorio
    • 1
    • 2
  • A. Spada
    • 1
  • A. Conti
    • 1
    • 2
  • G. Grugni
    • 1
  • F. Morabito
    • 1
  • G. Faglia
    • 2
  1. 1.Centro Auxologico ItalianoMilanoItaly
  2. 2.Istituto di Scienze EndocrineUniversità degli Studi di MilanoMilanoItaly

Personalised recommendations