(a) Geometric mean ± SE. GH levels during fasting (●) and fasting plus GHA (○). (b) Geometric mean ± SE. GH levels on each study day consisting of a basal period and HEC. GH levels were elevated during fasting (●) and fasting plus GHA (○) compared with control (▲). ^§GH levels decreased during the HEC after fasting and fasting plus GHA (P < 0.01). (c) Mean ± SE. IGF-I levels during fasting (●) and fasting plus GHA (○). (d) Correlation between serum pegvisomant levels and the GHA-induced reduction in serum IGF-I levels (ΔIGF-I).