
human growth hormone
clinical measurement, response to hypoglycemia and suppression by
corticosteroids
a standard test of growth-hormone secretory ca-
pacity, based on radioimmunoassay of plasma growth
hormone after insulin hypoglycemia, is described.  in
normal subjects a standard insulin tolerance test, caus-
ing an average blood glucose drop to 34 per cent of
resting values, produced a mean rise in growth hor-
mone to 45.2 millimicrogm. per milliliter at one hour,
with a total range of 25 to 70 millimicrogm. per mil-
liliter.  no response was observed in 5 hypopituitary
subjects.
under comparable hypoglycemic stimulation glu-
cocorticoid-treated patients showed a marked in-
hibition of the growth-hormone response, which was
related to dose.  subjects receiving more than 60 mg.
of cortisol equivalent per day showed a mean plasma
rise to 6.7 millimicrogm. per milliliter (range, 1.5
to 13 millimicrogm.).  subjects receiving 20 to 60 mg.
of cortisol equivalent per day showed a mean rise to
16.6 millimicrogm. per milliliter (range, 13 to 20
millimicrogm.).
inhibition of human growth hormone was also
affected by duration of glucocorticoid treatment, be-
ing greater with long-term than with short-term ad-
ministration.
