Our results demonstrate that ghrelin increases the gastric emptying rate in normal humans. The effect does not seem to be mediated via GH or motilin but may be mediated by the vagal nerve or directly on ghrelin receptors in the stomach. Ghrelin receptor agonists may have a role as prokinetic agents.

The incretin effect of GIP and GLP-1 differs as GLP-1 exerts a strong glucoregulatory incretin through inhibition of gastric emptying, which GIP does not. Thus, GLP-1 as incretin mimetic may offer unique benefits in terms of weight loss in treatment of type 2 diabetes.

Six patients (21–50 years) with growth hormone deficiency and panhypopituitarism were given recombinant growth hormone, somatropin, 0.04–0.1 U·kg·body wt−1·day−1, for 12 months. All patients reported improved well-being with increased working capacity. Bone mineral density, as measured by single photon absorptiometry at two sites on the forearm, showed increased values in 5/6 patients after 12 months when measured at the most distal site (predominantly trabecular bone) and in 4/6 at the more proximal site (predominantly cortical bone). Five patients continued therapy for an additional year and after 18 months a significant increase in bone mineral density was seen at both the distal and proximal sites. The mean annual increase in bone mineral density was 12.0±0.6 (sem)% and 3.8±1.3% at the distal and proximal sites, respectively. In a growth hormone deficient control group without growth hormone therapy, the corresponding values were −2.4±0.6% and −1.9±0.4%, respectively. Lean body mass, estimated anthropometrically, increased significantly after 12 months and total body potassium, measured by whole body counting technique, increased in 4/6 patients. During growth hormone treatment, the IGF-1 values were above the mean values for age and 50% of the values were above the mean + 2 SD. B-glucose, P-insulin, serum IGF-2, procollagen-III peptide and phosphate increased and urea, creatinine and IGF-binding protein-1 decreased during treatment. The beneficial effects of growth hormone substitution, especially on bone mineral density, indicate that growth hormone substitution should be considered in all patients with hypopituitarism and growth hormone deficiency, irrespective of age.

Abstract. In a double-blind cross-over study with recombinant methionyl growth hormone (GH) and placebo during 12 weeks, the effect of GH substitution therapy (0.5-0.6 IU · kg−1 · week−1) on physical performance, muscle strength, bone mineral density, and mood and cognitive functions was investigated in 6 GH-deficient adults. During GH substitution serum concentrations of insulin-like growth factor-I and procollagen-III peptide increased in all 6 patients, whereas concentrations of serum urea decreased. Five of the patients identified the GH period and reported improved well-being with increased mental alertness and vitality and improved physical capacity and muscle strength. There was, however, no change of the isokinetic muscle strength during GH substitution therapy, and the working capacity on the bicycle ergometer was just slightly improved in some patients. The bone mineral density was low and unchanged in all patients. Mood and cognitive functions did not change during GH therapy. A reversible fluid retention was observed in one patient during the GH period. In conclusion, short-term GH substitution therapy to GH-deficient adults induced a subjective improvement of general wellbeing. Longer treatment periods will be necessary to establish the effect on physical capacity, muscle strength, bone mineral density, and mood and cognitive functions.