Expansion of Extracellular Volume and Suppression of Atrial Natriuretic Peptide after Growth Hormone Administration in Normal Man

Abstract

Sodium retention and symptoms and signs of fluid retention are commonly recorded during GH administration in both GH-deficient patients and normal subjects. Most reports have however, been casuistic or uncontrolled. In a randomized double blind placebo-controlled cross-over study we therefore examined the effect of 14-day GH administration (12 IU sc at 2000 h) on plasma volume, extracellular volume (ECV), atrial natriuretic peptide (ANP), arginine vasopressin, and the renin angiotensin system in eight healthy adult men. A significant GH induced increase in serum insulin growth factor I was observed. GH caused a significant increase in ECV (L): 20.45 +/- 0.45 (GH), 19.53 +/- 0.48 (placebo) (P less than 0.01), whereas plasma volume (L) remained unchanged 3.92 +/- 0.16 (GH), 4.02 +/- 0.13 (placebo). A significant decrease in plasma ANP (pmol/L) after GH administration was observed: 2.28 +/- 0.54 (GH), 3.16 +/- 0.53 (placebo) P less than 0.01. Plasma aldosterone (pmol/L): 129 +/- 14 (GH), 89 +/- 17 (placebo), P = 0.08, and plasma angiotensin II (pmol/L) levels: 18 +/- 12 (GH), 14 +/- 7 (placebo), P = 0.21, were not significantly elevated. No changes in plasma arginine vasopressin occurred (1.86 +/- 0.05 pmol/L vs. 1.90 +/- 0.05, P = 0.33). Serum sodium and blood pressure remained unaffected. Moderate complaints, which could be ascribed to water retention, were recorded in four subjects [periorbital edema (n = 3), acral paraesthesia (n = 2) and light articular pain (n = 1)]. The symptoms were most pronounced after 2-3 days of treatment and diminished at the end of the period. In summary, 14 days of high dose GH administration caused a significant increase in ECV and a significant suppression of ANP.

The visceral adiposity index is associated with insulin sensitivity and IGF-I levels in adults with growth hormone deficiency

“…However, DEXA cannot distinguish between body cell mass and water and consequently these data may not be accurate since GHT is associated with an increase in the intracellular water component [37]. Computed tomography and MRI are two of the most sensitive methods that could lead to a reliable estimate of visceral fat, but both procedures require expensive specialized equipment and in this light the VAI is a clinical index derived from MRI-based studies and represents a better indicator of adipose dysfunction [17].…”

Effect of hydration on exercise-induced growth hormone response

“…In both groups of patients, body¯uid is normalized after, respectively, GH treatment and surgical treatment of the hypophysis. In healthy men, the pharmacological administration of GH also raises body-¯uid volume (2). The action of GH is thought to be mediated by aldosterone.…”

Effect of short-term GH and testosterone administration on body composition and glucose homoeostasis in men receiving chronic glucocorticoid therapy

“…The major limitation is the potential that some of the changes in skeletal muscle mass are secondary to changes in ECW. Previously it has been demonstrated that both short-and long-term administration of GH increases ECW (39,40). Testosterone also increases ECW, an effect amplified when co-administered with GH (41).…”