Figure 3. Intranasal GHRH decreases circulating GH concentrations.

Mean (± SEM) serum concentrations of GH during nocturnal wakefulness following intranasal administration of 600 µg GHRH_1–44 (black dots, solid line) and placebo (white dots, dashed line), respectively. Administration of GHRH and placebo took place after encoding of declarative and procedural memory tasks that were retrieved 11 hours later after encoding of an interference word pair list. N = 12, * P<0.05.