Observations on the responsiveness of human subjects to human growth hormone

Abstract

A B S T R A C T The effect of human growth hormone (HGH) on the N, P, Na, and K balance, and on the body weight (BW) of three groups of subjects was measured. In group I were nine cases (age 6-69) with HGH deficiency; in group II, eight cases (age 9-79) with normal endogenous HGH; in group III, four cases with myotonic dystrophy (age 45-51). After a 7 day control period, the hormone was administered for 7 days. Each subject was tested with three doses of HGH: dose A, 0.0168 U/kg BW"' per day; dose B, 0.0532 U/kg BW3'4 per day; dose C, 0.168 U/kg BW314 per day.In group I, the responsiveness to HGH declined with age. Two subjects aged 6 yr responded to all three doses of HGH with positive balances in N, P, Na, and K and increases in BW. At ages 15-17, responses were obtained only to doses B and C in three cases, and only to dose C in two cases. Two subjects, aged 42 and 69, responded only to dose C. Not only did the threshold dose increase with age in group I, but the magnitude of the responses declined with age as well.Patients of group II were less responsive to all doses of HGH than were patients of group I at comparable age. None responded to dose A or dose B. All responded to dose C, but the increments in balances and in BW stimulated by this dose were only one-third to one-half as great as in HGH-deficient subjects of similar age.Three patients of group III responded to all three doses of HGH, and one responded to doses B and C. The responses were similar in magnitude to those in the

Diurnal Variation in the Responsiveness of Human Subjects to Human Growth Hormone

“…pituitary hormones. Criteria for establishing deficiency of HGH, adrenocorticotropin, thyroid-stimulating hormone, gonadotropins, or antidiuretic hormone were as described before (1). Replacement doses for these deficiencies were: cortisol, 15-25 mg daily, administered at either 7 a.m. or 10 p.m. as specified; thyroxine, 0.2-0.3 mg daily given at 8 am.…”

“…As indicators of response, we measured increments in daily balances of N, P, Na, and K and in body weight (BW). The results of these ex-1 Previous studies (1,3) have shown that both categories are 5-10 times more responsive to the anabolic effects of HGH than normal individuals. The minimal effective dose for the anabolic effect of HGH in normals is 0.168-0.532 U/kg BW3/' daily, compared to 0.0532-0.168 U/kg BW3'4 for the patients cited.…”

“…Daily injection of about 0.05-0.15 U/kg BW"'4 (the usual dose in long-term treatment of growth retardation) in short children with normal endogenous GH generally does not accelerate growth (9,10). GH deficient children are more responsive; doses between 0.015 and 0.15 U/kg BW"4 usually elicit an acute anabolic response (1). Replacement treatment with HGH at 0.05-0.15 U/kg BW"' accelerates growth in these individuals (11)(12)(13)(14), although the growth response is variable and sometimes disappointing (15,16).…”

“…Adult subjects with myotonic and limb-girdle muscular dystrophies also are more sensitive than normals to the anabolic action of 0.015-0.15 U/kg BW"4 (1,3); the hormone consequently is being evaluated as a possible form of treatment for these types of dystrophy.…”

Whole Body Nitrogen Kinetics and Their Relationship to Growth in Short Children Treated with Recombinant Human Growth Hormone

“…For this reason, before the availability of a growth hormone RIA, improvement in nitrogen balance after growth hormone administration was used routinely for diagnosis of growth hormone deficiency and for assessment of therapeutic response (1 3-22). Even after the measurement of plasma growth hormone concentration became practical, testing the subject's nitrogen retention response to growth hormone administration remained a clinical and investigative tool (23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38).…”