Abstract
1 Animal studies have shown that adrenaline and noradrenaline are involved in the control of pituitary function. As very few data on this topic were available in man, some studies were carried out mainly in young normal volunteers using guanfacine, a new drug with central α-adrenoceptor properties.
2 Single oral doses of guanfacine 1 or 2 mg increased GH secretion. After 90-180 min, this increase was significant for the 2 mg dose. No effect on prolactin, ACTH, FSH and LH plasma levels was recorded. Four days of treatment with guanfacine showed:
(a) no additional stimulation of GH released by insulin;
(b) no effect on resting levels of prolactin and on prolactin released by metoclopramide, but a significant decrease of prolactin released by insulin;
(c) a statistically significant (P < 0.01) but biologically unimportant increase in LH secretion (Δ = 1.58mg/ml);
(d) a non-significant decrease of ACTH released by metyrapone (an 11-β-hydroxylase inhibitor) but a significant (P < 0.01) decrease in ACTH released by stress (insulin- induced hypoglycaemia).
3 A 7-d treatment period with guanfacine (3 mg daily) showed that the drug did not have a sustained stimulatory effect on GH and LH secretion in man.
4 These data on hormonal balance support the assumption that, in man, the central α-adrenergic system exerts a stimulatory control on GH secretion and that an adrenergic pathway, hypothalamic or extrahypothalamic, may be involved in the inhibitory control of prolactin and ACTH release induced by stress.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Girard J., Baumann J. B., Bühler U., Zuppinger K., Haas H. G., Staub J. J., Wyss H. I. Cyproteroneacetate and ACTH adrenal function. J Clin Endocrinol Metab. 1978 Sep;47(3):581–586. doi: 10.1210/jcem-47-3-581. [DOI] [PubMed] [Google Scholar]
- Hwang P., Guyda H., Friesen H. A radioimmunoassay for human prolactin. Proc Natl Acad Sci U S A. 1971 Aug;68(8):1902–1906. doi: 10.1073/pnas.68.8.1902. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lancranjan I., Marbach P. Effect of antihypertensive drugs on growth hormone secretion. Br Med J. 1977 Jun 4;1(6074):1472–1473. doi: 10.1136/bmj.1.6074.1472-d. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lancranjan I., Marbach P. New evidence for growth hormone modulation by the alpha-adrenergic system in man. Metabolism. 1977 Nov;26(11):1225–1230. doi: 10.1016/0026-0495(77)90115-9. [DOI] [PubMed] [Google Scholar]
- Lancranjan I., del Pozo E., Ohnhaus E. Inhibitory effect of guanfacine, a central alpha-adrenoceptor agonist, on prolactin secretion stimulated by insulin-induced hypoglycemia. J Clin Endocrinol Metab. 1978 Sep;47(3):671–674. doi: 10.1210/jcem-47-3-671. [DOI] [PubMed] [Google Scholar]
- Paakkari I., Karppanen H., Paakkari P. Site and mode of action of clonidine in the central nervous system. Acta Med Scand Suppl. 1976;602:106–109. doi: 10.1111/j.0954-6820.1977.tb07657.x. [DOI] [PubMed] [Google Scholar]
- Rosner J. M., Nagle C. A., de Laborde N. P., Pedroza E., Badano A., Figueroa Casas P. R., Carril M. Plasma levels of norepinephrine (NE) during the periovulatory period and after LH-RH stimulation in women. Am J Obstet Gynecol. 1976 Mar 15;124(6):567–572. doi: 10.1016/0002-9378(76)90056-9. [DOI] [PubMed] [Google Scholar]
- Ruch W., Jaton A. L., Bucher B., Marbach P., Doepfner W. Alpha adrenergic control of growth hormone in adult male rats. Experientia. 1976 Apr 15;32(4):529–531. doi: 10.1007/BF01920839. [DOI] [PubMed] [Google Scholar]
- Ruch W., Marbach P., Jaton A. L., Bucher B., Doepfner W. Adrenergic and dopaminergic control of growth hormone secretion in urethan anesthetized adult male rats. Horm Res. 1978;9(4):208–224. doi: 10.1159/000178915. [DOI] [PubMed] [Google Scholar]
- Scholtysik G., Lauener H., Eichenberger E., Bürki H., Salzmann R., Müller-Schweinitzer E., Waite R. Pharmacological actions of the antihypertensive agent N-amidino-2-(2,6-dichlorophenyl)acetamide hydrochloride (BS 100-141). Arzneimittelforschung. 1975 Oct;25(10):1483–1491. [PubMed] [Google Scholar]