390
COMMENTS
distinguish primary releasing hormone deficiency from primary pituitary hormone deficiency, J Clin Invest 51: 431, 1972. 10. Faglia, G., P. Beck-Peccoz, C. Ferrari, B. Ambrosi, A. Spada, P. Travaglini, and S. Paracchi, Plasma thyrotropin response to thyrotropin-releasing hormone in patients with pituitary and hypothalamic disorders,; Clin Endocrinol Metab 37: 595, 1973. 11. Patel, Y. C , and H. G. Burger, Serum thyrotropin (TSH) in pituitary and/or hypothalamic hypothyroidism: Normal or elevated basal levels and paradoxical responses to thyrotropin-releasing hormonej Clin Endocrinol Metab 37: 190, 1973. 12. Cacciari, E., F. Bemardi, S. Salardi, P. Tassoni, A. Cicognani, P. Pirazzoli, F. Zappulla, and S.
13. 14. 15.
16.
JCE & M . 1976 Vol 42 ( No 2
Zingoni, The thyrotropin-releasing hormone test in idiopathic pituitary dwarfism, Helv Paediatr Ada 29: 481, 1974. Van der Werff, Ten Bosch, J. J., Hypofisaire dwerggroei, Ned T Geneesk 106: 1282, 1962. Matsumoto, S., and H. Nakajima, Relationship between idiopathic pituitary dwarfism and breech delivery, Clin Endocrinol (Tokyo) 22: 291, 1974. Snyder, P. J., and R. D. Utiger, Inhibition of thyrotropin response to thyrotropin-releasing hormone by small quantities of thyroid hormones, ; Clin Invest 51: 2077, 1972. Oddie, T. H., and D. A. Fisher, Protein-bound iodine level during childhood and adolescence, ; Clin Endocrinol Metab 27: 89, 1967.
The Effect of Different Preparations of Human Growth Hormone on Plasma Renin Activity in Normal Males SOL EPSTEIN, DEREK LE ROITH, AND RALPH RABKIN* Department of Medicine, University of Cape Town Medical School, Observatory, Cape; and *Department of Medicine, University of the Witwatersrand Medical School, Johannesburg, South Africa ABSTRACT. The effect of acute administration of 2 preparations of growth hormone (hGH) on plasma renin activity (PRA) was studied in normal volunteers. 4 IU of standard, commercially available hGH (hGH II, Kabi, Sweden) were injected im into each of four normal subjects, and the PRA was determined in the basal state and at 30, 60, 120,180, and 240 min after injection. Free fatty acid (FFA) was determined basally and at 15 and 210 min post-injection. The study was repeated on a different day in the same group using highly purified hGH (hGH I, 4 IU) virtually free of arginine-vasopressin. Four other normal sub-
T
HE ADMINISTRATION OF exogenous human growth hormone (hGH) was found to lead to the retention of sodium in man (1). This observation, however, may have been clouded by the presence of posterior pituitary hormones as contaminants in the administered hGH preparation (2). In acromegalic subjects, various studies suggested that the relatively common incidence of hypertension might be related to abnormalities of the renin-angiotensin system and of water and electrolyte metabolism (1,3), although Palkovits et al. (4) found no relationship between growth hormone and the renin-angiotensin aldosterone system in rats. In normoReceived March 12, 1975.
jects received 12 IU standard hGH (hGH II, Kabi, Sweden). There was no significant difference in PRA values with 4 IU of either preparation or with 12 IU of hGH II in any of the groups, although mean PRA was elevated in two of the patients receiving 12 IU hGH II. A rise in FFA occurred in all subjects, indicating the biological activity of hGH preparations. The possible significance of these findings to the reninangiotensin system found in acromegaly is considered. (; Clin Endocrinol Metab 42: 390, 1976)
tensive acromegalics the renin-angiotensin system responds normally despite the presence of hypervolemia (5). This situation may represent adaptation to a chronic abnormality by ensuring appropriate perfusion to enlarged tissues. The effect of acute exogenous hGH administration on plasma renin activity (PRA) in normal man has been poorly documented. This study was undertaken to determine whether: a) the acute administration of 2 different preparations of hGH (one an arginine-vasopressin free preparation) would affect PRA in normal people, b) whether the response of PRA would differ with different preparations, and c) whether these responses might account for the findings in normotensive acromegalic subjects.
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391
COMMENTS TABLE 1. The effect of two hGH preparations on PRA (ng/ml/h) in normal males Time (min)
hGH I* (4IU)
hGH II (4IU)
hGH II (12 IU)
Curve area
Base area
Difference!
4.09 ± 1.79
1,085.25
924
-161.25
12.82
7.20 ±4.06
1,843.65
453.6
1,390.05
3.07
3.40
4.20 ± 1.13
926.4
1,461.6
-535.2
1.80
1.52
0.36
1.48 ±0.64
353.4
556.8
-203.4
4.64
6.37
1.48
2.68
3.64 ± 1.71
903.75
919.2
-15.45
7.62
6.78
4.84
7.53
7.56
6.42 ± 1.52
1,565.55
1,005.6
559.95
2.53
6.73
3.60
7.13
7.73
3.45
5.19 ±2.24
1,396.95
607.2
789.75
4.
6.92
6.48
4.24
6.08
4.88
4.92
5.58 ± 1.05
1,294.2
1,660.8
-366.6
5.
3.60
6.68
20.68
11.44
7.52
5.56
9.24 ±6.17
2,489.4
864
1,625.4
6.
2.92
3.36
6.36
6.60
2.52
8.08
4.97 ± 2.32
1,220.4
700.8
7.
5.12
6.44
5.04
3.80
7.24
5.32
5.49 ± 1.19
1,318.8
1,228.8
8
8.2
8.28
5.56
10.96
8.44
9.14 ±2.69
2,142
1,968
Patient
0
30
60
120
180
240
1.
3.85
3.24
2.08
5.83
6.69
2.85
2.
1.89
4.13
10.44
8.19
5.76
3.
6.09
4.91
4.23
3.25
4.
2.32
1.52
1.40
1.
3.83
2.87
2.
4.19
3.
Mean
13.4
± SD
519.6 90 174
* The group receiving 4 IU of hGH I comprised the same subjects receiving 4 IU of hGH II. f One-way analysis of variance of above results revealed no significant differences between the two preparations and the increased dosages of hGH II.
Materials and Methods Two groups of male volunteers, between 20 and 46 years old, were studied. All were normotensive with no evidence of hepatic, renal, or endocrine abnormalities. All were , on normal diets containing approximately 140 mEq sodium per day. Informed consent was obtained from each volunteer. Group I consisted of four subjects who received two different preparations of hGH (hGH I1 and hGH II2) on two separate days. Four IU of either hGH I or hGH II were injected im. Venous blood samples were col1 hGH II was the standard commercially available hGH (Kabi, Sweden). 2 hGH I was highly purified hGH containing only 9.3 pg Arginine vasopressin (determined by radioimmunoassay—by kind permission of Dr. G. L. Robertson) per unit of hGH.
lected via an indwelling cannula, basally at the time of injection and at 30, 60, 120, 180, and 240 min after injection for PRA determinations. Free fatty acids (FFA) were measured basally and at 15 and 210 min post-injection. All volunteers were fasted overnight but allowed free access to water. The studies were carried out in the morning with volunteers recumbent. Each study was repeated using the other preparation in a random manner on a different day. Group II. Four volunteers fasted overnight except for free access to water and had 12 IU hGH II (Kabi) injected im. Blood was collected as with Group I for PRA and FFA. Blood for PRA was collected in pre-chilled EDTA tubes and then immediately placed on ice, centrifuged, and the plasma was frozen until assayed. PRA was determined by radioimmunoassay, according to the method of Haber et al.(6). Our normal range in the supine position was 2-8
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392
JCE & M • 1976 Vol 42 • No 2
COMMENTS
TABLE 2. The effect of different hGH preparations on FFA (/u.Eq/L) in normal males
Time (min)
hGH I (4 IU)* (N = 4)t FFA
hGH II (4IU) (N = 4) FFA
hGH II (12 IU) (N = 4) FFA
0 15 210
383.0 347.9 596.9
293.1 421.7 893.4
568.25 629.25 891.00
* The group receiving 4 IU hGH I comprised the same subjects receiving 4 IU hGH II. t N = number of subjects. ng/ml/h. Intra-assay variation was 8% and inter-assay variation 14%. All samples were assayed in one batch. FFA were determined according to the method of Dole and Meinertz (7). Statistical analysis was calculated from the area under the curve for each of the 12 subjects and an analysis of variance was performed on the difference between the curve area and the base area (8,9).
Results The administration of pure or commercially available hGH in 4 IU or 12 IU dosages did not elevate mean PRA, measured during a 240minute period, above our normal range in 6 of 8 subjects (Table 1). Two subjects who received 12 IU hGH II had a mean rise in PRA above our normal range. Patient 5 had a value of PRA of 20.68 at 120 minutes which we cannot explain. There was no significant difference, however, between the results of the groups treated with either 4 IU hGH I or hGH II and between the group with 12 IU hGH II (Table 1). To verify that the hGH preparations used were biologically active, the effect on FFA was measured. In all subjects, plasma samples taken at 210 min after injection showed a rise in FFA indicating biological activity (Table 2).
Discussion On studying 8 normal subjects we found that the acute administration of hGH did not cause PRA to rise above our normal range in 6 of the 8. In addition, there appeared to be no significant difference in the PRA response with the type of hGH preparation used and the amount of hGH administered. These findings are in keeping with Palkovits' (4). Alternately, it can be argued that the mean rise in PRA that occurred in 2 of the
8 subjects with the larger dose of hGH, although modest, might if persistent be sufficient to result in retention of sodium and water with expansion of blood volume and to promote hypertension. The lack of acute sodium retention after growth hormone administration (10) makes this unlikely. Nevertheless, a mild rise in PRA might explain the presence of a normal renin angiotensin system in acromegalics despite the expanded blood volume.
Acknowledgments Statistical analysis was performed by the National Biostatistical Research Centre of the South African Medical Research Council. We would like to thank Mrs. H. Brodovcky for expert technical assistance. References 1. Biglieri, E. G., C. O. Watlington, and P. H. Forsham, Sodium retention with human growth hormones and its subtractions, J Clin Endocrinol Metab 21: 361, 1961. 2. Baumann, G., E. J. Rayfield, L. I. Rose, G. H. Williams, and J. F. Dingman, Trace contamination of corticotropin and human growth hormone with vasopressin—Clinical significance, J Clin Endocrinol Metab 34: 801, 1972. 3. Balzer, R., and E. P. McCullagh, Hypertension in acromegaly, Am J Med Sci 237: 449, 1959. 4. Palkovits, N., W. de Jong, B. Van Der Wai, and D. De Wied, Effect of adrenocorticotrophin and growth hormone on aldosterone production and plasma renin activity in chronically hypophysectomized sodium deficient rats, J Endocrinol 47: 243, 1970. 5. Strauch, G., M. B. Valloton, Y. Touitou, and H. Brifaire, Renin angiotensin-aldosterone system in normotensive and hypertensive patients with acromegaly, N Engl J Med 287: 795, 1972. 6. Haber, E., T. Koemer, L. B. Page, B. Kliman, and A. Purnode, Application of a radioimmunoassay for angiotensin I to physiologic measurements of plasma renin activity in normal human subjects, J Clin Endocrinol Metab 29: 1369, 1969. 7. Dole, V. P., and H. Meinertz, Microdetermination of long-chain fatty acids in plasma and tissues, J Biol Chem 235: 2595, 1960. 8. Henrici, P., Elements of Numerical Analysis, John Wiley and Sons, New York, 1964. 9. Kendall, M. G., S. Stuart, Advanced Theory of Statistics, vol 3, Charles Griffin and Company, London, 1968. 10. Rabkin, R. S., S. Epstein, and M. Swann, Effect of growth hormone on renal sodium and water excretion, Horm Metab Res 7: 139, 1975.
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COMMENTS
distinguish primary releasing hormone deficiency from primary pituitary hormone deficiency, J Clin Invest 51: 431, 1972. 10. Faglia, G., P. Beck-Peccoz, C. Ferrari, B. Ambrosi, A. Spada, P. Travaglini, and S. Paracchi, Plasma thyrotropin response to thyrotropin-releasing hormone in patients with pituitary and hypothalamic disorders,; Clin Endocrinol Metab 37: 595, 1973. 11. Patel, Y. C , and H. G. Burger, Serum thyrotropin (TSH) in pituitary and/or hypothalamic hypothyroidism: Normal or elevated basal levels and paradoxical responses to thyrotropin-releasing hormonej Clin Endocrinol Metab 37: 190, 1973. 12. Cacciari, E., F. Bemardi, S. Salardi, P. Tassoni, A. Cicognani, P. Pirazzoli, F. Zappulla, and S.
13. 14. 15.
16.
JCE & M . 1976 Vol 42 ( No 2
Zingoni, The thyrotropin-releasing hormone test in idiopathic pituitary dwarfism, Helv Paediatr Ada 29: 481, 1974. Van der Werff, Ten Bosch, J. J., Hypofisaire dwerggroei, Ned T Geneesk 106: 1282, 1962. Matsumoto, S., and H. Nakajima, Relationship between idiopathic pituitary dwarfism and breech delivery, Clin Endocrinol (Tokyo) 22: 291, 1974. Snyder, P. J., and R. D. Utiger, Inhibition of thyrotropin response to thyrotropin-releasing hormone by small quantities of thyroid hormones, ; Clin Invest 51: 2077, 1972. Oddie, T. H., and D. A. Fisher, Protein-bound iodine level during childhood and adolescence, ; Clin Endocrinol Metab 27: 89, 1967.
The Effect of Different Preparations of Human Growth Hormone on Plasma Renin Activity in Normal Males SOL EPSTEIN, DEREK LE ROITH, AND RALPH RABKIN* Department of Medicine, University of Cape Town Medical School, Observatory, Cape; and *Department of Medicine, University of the Witwatersrand Medical School, Johannesburg, South Africa ABSTRACT. The effect of acute administration of 2 preparations of growth hormone (hGH) on plasma renin activity (PRA) was studied in normal volunteers. 4 IU of standard, commercially available hGH (hGH II, Kabi, Sweden) were injected im into each of four normal subjects, and the PRA was determined in the basal state and at 30, 60, 120,180, and 240 min after injection. Free fatty acid (FFA) was determined basally and at 15 and 210 min post-injection. The study was repeated on a different day in the same group using highly purified hGH (hGH I, 4 IU) virtually free of arginine-vasopressin. Four other normal sub-
T
HE ADMINISTRATION OF exogenous human growth hormone (hGH) was found to lead to the retention of sodium in man (1). This observation, however, may have been clouded by the presence of posterior pituitary hormones as contaminants in the administered hGH preparation (2). In acromegalic subjects, various studies suggested that the relatively common incidence of hypertension might be related to abnormalities of the renin-angiotensin system and of water and electrolyte metabolism (1,3), although Palkovits et al. (4) found no relationship between growth hormone and the renin-angiotensin aldosterone system in rats. In normoReceived March 12, 1975.
jects received 12 IU standard hGH (hGH II, Kabi, Sweden). There was no significant difference in PRA values with 4 IU of either preparation or with 12 IU of hGH II in any of the groups, although mean PRA was elevated in two of the patients receiving 12 IU hGH II. A rise in FFA occurred in all subjects, indicating the biological activity of hGH preparations. The possible significance of these findings to the reninangiotensin system found in acromegaly is considered. (; Clin Endocrinol Metab 42: 390, 1976)
tensive acromegalics the renin-angiotensin system responds normally despite the presence of hypervolemia (5). This situation may represent adaptation to a chronic abnormality by ensuring appropriate perfusion to enlarged tissues. The effect of acute exogenous hGH administration on plasma renin activity (PRA) in normal man has been poorly documented. This study was undertaken to determine whether: a) the acute administration of 2 different preparations of hGH (one an arginine-vasopressin free preparation) would affect PRA in normal people, b) whether the response of PRA would differ with different preparations, and c) whether these responses might account for the findings in normotensive acromegalic subjects.
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391
COMMENTS TABLE 1. The effect of two hGH preparations on PRA (ng/ml/h) in normal males Time (min)
hGH I* (4IU)
hGH II (4IU)
hGH II (12 IU)
Curve area
Base area
Difference!
4.09 ± 1.79
1,085.25
924
-161.25
12.82
7.20 ±4.06
1,843.65
453.6
1,390.05
3.07
3.40
4.20 ± 1.13
926.4
1,461.6
-535.2
1.80
1.52
0.36
1.48 ±0.64
353.4
556.8
-203.4
4.64
6.37
1.48
2.68
3.64 ± 1.71
903.75
919.2
-15.45
7.62
6.78
4.84
7.53
7.56
6.42 ± 1.52
1,565.55
1,005.6
559.95
2.53
6.73
3.60
7.13
7.73
3.45
5.19 ±2.24
1,396.95
607.2
789.75
4.
6.92
6.48
4.24
6.08
4.88
4.92
5.58 ± 1.05
1,294.2
1,660.8
-366.6
5.
3.60
6.68
20.68
11.44
7.52
5.56
9.24 ±6.17
2,489.4
864
1,625.4
6.
2.92
3.36
6.36
6.60
2.52
8.08
4.97 ± 2.32
1,220.4
700.8
7.
5.12
6.44
5.04
3.80
7.24
5.32
5.49 ± 1.19
1,318.8
1,228.8
8
8.2
8.28
5.56
10.96
8.44
9.14 ±2.69
2,142
1,968
Patient
0
30
60
120
180
240
1.
3.85
3.24
2.08
5.83
6.69
2.85
2.
1.89
4.13
10.44
8.19
5.76
3.
6.09
4.91
4.23
3.25
4.
2.32
1.52
1.40
1.
3.83
2.87
2.
4.19
3.
Mean
13.4
± SD
519.6 90 174
* The group receiving 4 IU of hGH I comprised the same subjects receiving 4 IU of hGH II. f One-way analysis of variance of above results revealed no significant differences between the two preparations and the increased dosages of hGH II.
Materials and Methods Two groups of male volunteers, between 20 and 46 years old, were studied. All were normotensive with no evidence of hepatic, renal, or endocrine abnormalities. All were , on normal diets containing approximately 140 mEq sodium per day. Informed consent was obtained from each volunteer. Group I consisted of four subjects who received two different preparations of hGH (hGH I1 and hGH II2) on two separate days. Four IU of either hGH I or hGH II were injected im. Venous blood samples were col1 hGH II was the standard commercially available hGH (Kabi, Sweden). 2 hGH I was highly purified hGH containing only 9.3 pg Arginine vasopressin (determined by radioimmunoassay—by kind permission of Dr. G. L. Robertson) per unit of hGH.
lected via an indwelling cannula, basally at the time of injection and at 30, 60, 120, 180, and 240 min after injection for PRA determinations. Free fatty acids (FFA) were measured basally and at 15 and 210 min post-injection. All volunteers were fasted overnight but allowed free access to water. The studies were carried out in the morning with volunteers recumbent. Each study was repeated using the other preparation in a random manner on a different day. Group II. Four volunteers fasted overnight except for free access to water and had 12 IU hGH II (Kabi) injected im. Blood was collected as with Group I for PRA and FFA. Blood for PRA was collected in pre-chilled EDTA tubes and then immediately placed on ice, centrifuged, and the plasma was frozen until assayed. PRA was determined by radioimmunoassay, according to the method of Haber et al.(6). Our normal range in the supine position was 2-8
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392
JCE & M • 1976 Vol 42 • No 2
COMMENTS
TABLE 2. The effect of different hGH preparations on FFA (/u.Eq/L) in normal males
Time (min)
hGH I (4 IU)* (N = 4)t FFA
hGH II (4IU) (N = 4) FFA
hGH II (12 IU) (N = 4) FFA
0 15 210
383.0 347.9 596.9
293.1 421.7 893.4
568.25 629.25 891.00
* The group receiving 4 IU hGH I comprised the same subjects receiving 4 IU hGH II. t N = number of subjects. ng/ml/h. Intra-assay variation was 8% and inter-assay variation 14%. All samples were assayed in one batch. FFA were determined according to the method of Dole and Meinertz (7). Statistical analysis was calculated from the area under the curve for each of the 12 subjects and an analysis of variance was performed on the difference between the curve area and the base area (8,9).
Results The administration of pure or commercially available hGH in 4 IU or 12 IU dosages did not elevate mean PRA, measured during a 240minute period, above our normal range in 6 of 8 subjects (Table 1). Two subjects who received 12 IU hGH II had a mean rise in PRA above our normal range. Patient 5 had a value of PRA of 20.68 at 120 minutes which we cannot explain. There was no significant difference, however, between the results of the groups treated with either 4 IU hGH I or hGH II and between the group with 12 IU hGH II (Table 1). To verify that the hGH preparations used were biologically active, the effect on FFA was measured. In all subjects, plasma samples taken at 210 min after injection showed a rise in FFA indicating biological activity (Table 2).
Discussion On studying 8 normal subjects we found that the acute administration of hGH did not cause PRA to rise above our normal range in 6 of the 8. In addition, there appeared to be no significant difference in the PRA response with the type of hGH preparation used and the amount of hGH administered. These findings are in keeping with Palkovits' (4). Alternately, it can be argued that the mean rise in PRA that occurred in 2 of the
8 subjects with the larger dose of hGH, although modest, might if persistent be sufficient to result in retention of sodium and water with expansion of blood volume and to promote hypertension. The lack of acute sodium retention after growth hormone administration (10) makes this unlikely. Nevertheless, a mild rise in PRA might explain the presence of a normal renin angiotensin system in acromegalics despite the expanded blood volume.
Acknowledgments Statistical analysis was performed by the National Biostatistical Research Centre of the South African Medical Research Council. We would like to thank Mrs. H. Brodovcky for expert technical assistance. References 1. Biglieri, E. G., C. O. Watlington, and P. H. Forsham, Sodium retention with human growth hormones and its subtractions, J Clin Endocrinol Metab 21: 361, 1961. 2. Baumann, G., E. J. Rayfield, L. I. Rose, G. H. Williams, and J. F. Dingman, Trace contamination of corticotropin and human growth hormone with vasopressin—Clinical significance, J Clin Endocrinol Metab 34: 801, 1972. 3. Balzer, R., and E. P. McCullagh, Hypertension in acromegaly, Am J Med Sci 237: 449, 1959. 4. Palkovits, N., W. de Jong, B. Van Der Wai, and D. De Wied, Effect of adrenocorticotrophin and growth hormone on aldosterone production and plasma renin activity in chronically hypophysectomized sodium deficient rats, J Endocrinol 47: 243, 1970. 5. Strauch, G., M. B. Valloton, Y. Touitou, and H. Brifaire, Renin angiotensin-aldosterone system in normotensive and hypertensive patients with acromegaly, N Engl J Med 287: 795, 1972. 6. Haber, E., T. Koemer, L. B. Page, B. Kliman, and A. Purnode, Application of a radioimmunoassay for angiotensin I to physiologic measurements of plasma renin activity in normal human subjects, J Clin Endocrinol Metab 29: 1369, 1969. 7. Dole, V. P., and H. Meinertz, Microdetermination of long-chain fatty acids in plasma and tissues, J Biol Chem 235: 2595, 1960. 8. Henrici, P., Elements of Numerical Analysis, John Wiley and Sons, New York, 1964. 9. Kendall, M. G., S. Stuart, Advanced Theory of Statistics, vol 3, Charles Griffin and Company, London, 1968. 10. Rabkin, R. S., S. Epstein, and M. Swann, Effect of growth hormone on renal sodium and water excretion, Horm Metab Res 7: 139, 1975.
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