I. Medizinische Universitätsklinik, Division of Clinical Endocrinology and Diabetes Mellitus, Wien
GONADOTROPHIN-RELEASE UPON INTRAVENOUS ADMINISTRATION OF A LONG-ACTING ANALOGUE OF LUTEINIZING HORMONE-RELEASING HORMONE IN FEMALES WITH INCREASED PLASMA-ANDROGENS By H. Vierhapper, W. Waldhausl and P. Nowotny
ABSTRACT
D-Ser-(TBU)6-EA10-LH-RH, an analogue of luteinizing hormone-releasing hormone (LH-RH) with prolonged action evokes in normal male and female subjects a qualitatively different secretory pattern of LH, as peak levels are reached between 30 and 60 min in males and between 120 and 240 min in females. Females with increased production of adrenal andro- gens due to congenital adrenal hyperplasia (off substitution therapy; N = 8), idiopathic hirsutism (N = 1) and adrenocortical carcinoma (N = 2) present upon the administration of the LH-RH-analogue with a secretory pattern of LH and FSH which is qualitatively identical with that of normal female subjects, whereas the response of LH in these patients differs from that seen in normal males. Pre-treatment with dexamethasone did not induce any qualitative changes in the secretory response of LH and FSH upon the LH-RH-analogue in patients with increased endogenous production of adrenal androgens. A larger pool and/or a more pronounced de novo- synthesis of LH, which apparently is not altered by increased levels of adrenal androgens, may be the cause of the more pronounced and pro- longed increase of LH in female subjects following the administration of the LH-RH-analogue.
Previous studies about the action of D-Ser-(TBU)6-EA10-LH-RH (König et al. 1975) in normal male (Wiegelmann et al. 1976; Vierhapper et al. 1977) and female (Friedrich et al. 1978; Dericks-Tan et al. 1977) subjects have shown a prolonged response of LH and FSH in comparison to equimolar doses of
| Patient | BM | BA | BR | SM | DR | KR | SE | WA | BE | MH | PO | Normal (?) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Diagnosis | CAH | CAH | CAH | CAH | CAH | CAH | CAH | CAH | IH | AC | AC | |
| Chronol. age | 10 | 15 | 16 | 24 | 18 | 21 | 50 | 33 | 34 | 18 | 56 | |
| Bone age | 10 | 15 | 16 | mature | mature | mature | - | - | - | - | - | |
| Height (cm) | 152 | 162 | 157 | 155 | 150 | 150 | 150 | 160 | 169 | 160 | 170 | |
| Weight (kg) | 33 | 64 | 46 | 74 | 55 | 55 | 72 | 85 | 82 | 58 | 88 | |
| Salt loser | NO | NO | NO | NO | NO | NO | NO | NO | - | - | - | |
| Genital status | IV | III | IV | normal | 1 | normal | IV | normal | normal | I | normal | |
| Menstruation | 1ºAm. | 1ºAm. | 1ºAm. | irreg. | 2ºAm. | reg. | 1ºAm. | irreg. | irreg. | 1°Am. | menop. | |
| Partus | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 2 |
Plasma levels of androgens prior to/during treatment with dexamethasone (0.5 mg po, q. i. d.)
| AND | 825/36 | 665/36 | -/- ☒ | 265/68 | 190/145 | 63/21 | 837/84 | 347/83 | 138/49 | 536/734 | 633/- | 113± 50 (SD) |
| DHEA | 488/45 | 269/19 | -/- ☒ | 142/28 | 389/ 59 | 44/19 | 60/28 | 1500/35 | 134/72 | 850/850 | 162/- | 61 ± 44 (SD) |
| T | 304/32 | 215/32 | 457/24 | 138/25 | 58/ 27 | 20/15 | 390/37 | 115/26 | 50/43 | 60/ 99 | 78/- | 18± 6 (SD) |
| Urinary excretion of androgens | ||||||||||||
| Pregnanediol | 9.4 | 20.5 | 13.7 | 4.7 | 1.0 | 0.05 | 5.3 | 7.1 | 0.7 | 4.2 | 0.10-9.50 | |
| Pregnanetriol | 107.0 | 189.0 | 207.0 | 21.1 | 5.1 | 2.00* | 36.1 | 11.5 | 2.0 | 5.5 | 0.10-3.10 | |
| DHEA | 0.3 | 3.0 | 2.2 | 0.9 | 1.2 | 0.01 | 0.6 | 5.0 | 0.1 | 72.8 | 0.04-0.43 | |
| Aetiocholanolone | 2.3 | 7.4 | 10.5 | 3.9 | 4.1 | 0.20 | 2.9 | 10.5 | 1.6 | 31.1 | 0.34-1.35 | |
% After ACTH: 35.3.
LH-RH. In this study we have evaluated the influence of endogenously in- creased levels of adrenal androgens upon the secretory response of LH and FSH following the administration of an iv bolus of the LH-RH-analogue.
MATERIALS AND METHODS
The clinical data of S females suffering from congenital adrenal hyperplasia (CAH) due to 21-hydroxylase-deficiency, of one patient with idiopathic hirsutism (IH) and 2 patients with adrenocortical carcinoma (AC) are shown in Table 1. The diagnosis was established by gas-chromatographic analysis of urinary steroids (Luyten & Rutten 1974; Pfaffenberger & Horning 1975) under basal conditions (i. e .: off substitution therapy for at least 3 days), during treatment with dexamethasone and after stimulation with ACTH. Five healthy male subjects (aged 19-23 years) and 5 healthy females (aged 20-28 years; first week of menstrual cycle) served as controls. All patients and normal subjects were informed about the aim and possible risks of the study before giving their free consent to participate.
The LH-RH-analogue D-Ser-(TBU)6-EA10-LH-RH; Hoe 766, Hoechst AG, Frankfurt- Main, FRG) was administered as an iv bolus (10 µg). Blood samples for the determina- tion of luteinizing hormone (LH) and follicle stimulating hormone (FSH) were drawn at -15, 0, 10, 20, 30, 60, 120, 240, 360, 480 and 1440 min through an indwelling venous catheter. The mean sum of increments above basal levels of LH and FSH at 10, 20, 30 and 60 min (period I), at 120, 240, 360 and 480 min (period II) and at 10, 20, 30, 60, 120, 240, 360, 480 and 1440 min (total response) was calculated in each case. In addi- tion, plasma samples for the determination of androstenedione (AND), dehydroepiandro- sterone (DHEA) and testosterone (T) were obtained immediately before the administra- tion of the LH-RH-analogue in each patient (Table 1).
In 6 patients with CAH, one patient with idiopathic hirsutism and one patient with adrenocortical carcinoma the administration of the LH-RH-analogue was repeated dur- ing treatment with dexamethasone (0.5 mg po, q. i. d) which had been started at least 3 days previously. The administration of the LH-RH-analogue was also repeated in 3 patients with CAH (BM, BA and BR) 7 days after the im administration of 100 mg testosterone propionate and 250 mg testosterone oenanthate (Testoviron - Depot®, Sche- ring) during continued treatment with dexamethasone.
LH and FSH were determined radioimmunologically (Behringwerke/Marburg). Intra- assay variability was 5.6% for LH and 7.3% for FSH. Inter-assay variability was 9.5 % for LH and 8.6% for FSH. One ng LH equals 66 ng hLH LER 907, while 1 ng FSH equals 168 ng hFSH LER 907.
Androstenedione (4-androstene-3,17-dione; AND), dehydroepiandrosterone (38-hy- droxy-5-androsten-17-one; DHEA) and testosterone (178-hydroxy-4-androsten-3-one; T) were purified from plasma samples by thin layer chromatography as reported pre- viously (Waldhausl et al. 1978). Radioimmunoassays for the determination of steroids were performed using antiserum against androstenedione (Steranti A001; 1 unit per tube), dehydroepiandrosterone (Endocrine Sciences D17/113; final dilution 1:400 000), testosterone (Steranti A002; 1 unit per tube). Borate buffer containing 0.1 g bovine serum albumin was used for the radioimmunoassay of AND and DHEA, whereas dilutions for the assay of testosterone were made by 0.04 M phosphate buffer, pH 7.4, containing 0.5 % gelatine and 0.02 sodium azide. Labelled hormones (The Radiochemical Centre, Amersham) were dehydro[7(n)-3H]epiandrosterone (10-25 Ci/mmol), [1,2,6,7(n)-3H]-
| Patient | Controls (?) (x ± SE) | Controls (6) (x ± SE) | CAH (n = 6) (x ± SE) | SE | WA | BE | MH | PO |
|---|---|---|---|---|---|---|---|---|
| Diagnosis | (CAH) | (CAH) | (IH) | (AC) | (AC) | |||
| -15 | 9.83 | 7.00 | 5.03 | 1.64 | 1.22 | |||
| 0 | 9.69 | 8.40 | 5.04 | 1.26 | 1.15 | |||
| x | 2.52 ± 0.37 | 1.69 ± 0.14 | 1.47 ± 0.50 | |||||
| Period I | ||||||||
| 10 | 5.78 ± 1.87 | 4.38 ± 0.75 | 5.38 ± 1.84 | 22.70 | 31.90 | 8.52 | 2.13 | 1.69 |
| 20 | 9.58 ± 4.32 | 8.24 ± 1.71 | 9.65 ± 3.16 | 32.05 | 42.90 | 14.29 | 2.26 | 4.19 |
| 30 | 9.90 ± 4.42 | 10.19 ± 2.08 | 15.77 ± 6.51 | 34.25 | 48.40 | 22.15 | 2.44 | 6.52 |
| 60 | 14.34 ± 5.50 | 10.62 ± 2.05 | 17.29 ± 6.43 | 37.95 | 47.60 | 27.30 | 2.81 | 7.78 |
| Period II | ||||||||
| 120 | 22.83 ± 9.87 | 8.46 ± 1.43 | 27.99 ± 10.19 | 42.55 | 69.10 | 43.90 | 6.17 | 8.91 |
| 240 | 26.98 ± 8.24 | 7.17 ± 0.80 | 22.44 ± 5.82 | 42.10 | 66.90 | 78.25 | 6.89 | 9.35 |
| 360 | 15.64 ± 3.81 | 5.04 ± 0.53 | 12.83 ± 2.92 | 27.40 | 32.40 | 56.60 | 5.52 | 9.06 |
| 480 | 9.60 ± 2.48 | 4.13 ± 0.52 | 6.90 ± 1.43 | 22.85 | 19.60 | 28.25 | 2.11 | 6.15 |
| 1440 | 2.87 ± 0.23 | 1.66 ± 0.24 | 2.52 ± 1.00 | 9.55 | 4.70 | 4.62 | 1.39 | 2.37 |
androstenedione (80-110 Ci/mmol), and [1,2,6,7(n)-3H] testosterone (80-110 Ci/mmol). 10 000 CPM of labelled steroid was added per tube. The inter-assay coefficient of varia- tion for steroid assays was less than 10.4 %, whereas the intra-assay coefficient of varia- tion was less than 7.4 % (n = 14).
Unless otherwise indicated, data are given as x + sr. Student’s t-test for matched and unmatched pairs was used for statistical evaluation.
RESULTS
Normal female subjects presented with higher basal levels of LH (2.52 + 0.37 ng/ml) than normal males (1.69 ± 0.14 ng/ml, P <0.05). Following the ad- ministration of the LH-RH-analogue peak levels of LH were reached after 120-240 min in normal females (26.98 ± 8.24 ng/ml) and after 30-60 min in normal males (10.62 + 2.05 ng/ml; Table 2). The overall sum of increments of LH above basal levels (0-1440 min; total response) was greater in females (94.9 + 36.1 ng/ml) than in males (44.6 + 8.4 ng/ml), although this difference was not significant. In normal females, the release of LH was greater in pe- riod II (65.0 ± 22.8 ng/ml) than in period I (29.6 ± 14.4 ng/ml, P < 0.05), whereas the greater share of LH was released during period I in normal males (26.6 ± 6.2 vs. 18.0 ± 2.6 ng/ml during period II), although this difference was not significant.
Basal levels of LH in 6 patients with CAH (1.47 ± 0.50 ng/ml) were in the range of normal male subjects, but lower than in normal females (P < 0.05). In these patients the LH-RH-analogue induced a rise of L.H to peak levels of 27.99 ± 10.19 ng/ml, which were reached after 120-240 min (Table 2). The release of LH in patients with CAH was greater during period II (64.3 + 15.5 vs. 40.9 + 16.7 ng/ml during period I), although this difference was not signi- ficant. Total response of LH in patients with CAH was 106.2 ± 26.0 ng/ml. Although basal levels of LH as well as the total response of LH upon the administration of the LH-RH-analogue were markedly higher in 2 further patients with CAH (SE and WA), the secretory response of LH in these pa- tients was similar to that observed in the other patients with CAH, as both patients presented with a greater share of LH-secretion during period II. The same observation was made in one patient with idiopathic hirsutism and 2 pa- tients with adrenocortical carcinoma (Table 2).
Basal levels of FSH were higher in normal female subjects (2.88 +0.28 ng/ml) than in normal males (1.76 ± 0.24 ng/ml, P <0.01) and higher than in 6 pa- tients with CAH (1.95 ± 0.24 ng/ml, P < 0.05).
Following the administration of the LH-RH-analogue peak levels of FSH were reached after 120-360 min in normal females (12.21 ± 0.92 ng/ml), after 120-240 min in normal males (3.87 + 0.93 ng/ml) and after 120-360 min in patients with CAH (11.87 ± 0.83 ng/ml; Table 3). In normal females, normal
| Patient | Controls (?) (x ± SE) | Controls (6) (x ± SE) | CAH (n = 6) (x ± SE) | SE | WA | BE | MH | PO |
|---|---|---|---|---|---|---|---|---|
| Diagnosis | (CAH) | (CAH) | (IH) | (AC) | (AC) | |||
| -15 | 18.95 | 2.50 | 3.65 | 2.10 | 0.82 | |||
| 0 | 18.80 | 2.50 | 3.71 | 1.88 | 0.74 | |||
| x | 2.88 ± 0.28 | 1.76 ± 0.24 | 1.95 ± 0.24 | |||||
| Period I | ||||||||
| 10 | 3.64 ± 0.25 | 1.92 ± 0.44 | 3.26 ± 0.72 | 21.60 | 4.70 | 3.82 | 2.28 | 0.94 |
| 20 | 5.09 ± 0.39 | 2.76 ± 0.72 | 4.91 ± 1.59 | 26.00 | 6.50 | 4.52 | 2.20 | 1.70 |
| 30 | 6.10 ± 0.51 | 3.15 ± 0.85 | 5.73 ± 1.97 | 27.35 | 7.30 | 5.26 | 2.42 | 2.33 |
| 60 | 7.14 ± 0.97 | 3.85 ± 1.14 | 6.84 ± 1.94 | 32.50 | 8.40 | 6.47 | 2.68 | 3.22 |
| Period II | ||||||||
| 120 | 9.18 ± 2.04 | 3.77 ± 1.00 | 10.23 ± 1.91 | 37.00 | 11.50 | 10.19 | 5.54 | 4.23 |
| 240 | 12.21 ± 0.92 | 3.87 ± 0.93 | 11.87 ± 0.83 | 40.05 | 15.00 | 17.57 | 6.18 | 4.86 |
| 360 | 10.47 ± 0.74 | 3.40 ± 0.90 | 10.35 ± 1.12 | 33.85 | 10.70 | 18.22 | 5.59 | 6.18 |
| 480 | 8.45 ± 0.75 | 3.04 ± 0.55 | 8.25 ± 0.88 | 30.90 | 8.60 | 12.40 | 3.28 | 4.79 |
| 1440 | 3.77 ± 0.24 | 1.40 ± 0.26 | 3.18 ± 0.29 | 18.00 | 3.60 | 4.19 | 1.44 | 2.32 |
males and patients with CAH, FSH release was greater (P <0.05) during period II (females: 28.8 + 4.2 ng/ml, males: 7.2 + 2.5 ng/ml, patients with during CAH: 31.3 + 2.3 ng/ml) than during period I (females: 10.5 ± 2.0 ng/ml, ts with males: 4.6 ± 2.1 ng/ml, patients with CAH: 14.0 ± 5.8 ng/ml). ng/ml,
The overall sum of increments above basal levels of FSH (0-1440 min; total response) was larger in normal females (40.2 + 5.8 ng/ml) than in normal n; total males (11.2 ± 4.3 ng/ml; P < 0.005). Total response of FSH in patients with
normal ts with CAH was 47.4 ± 7.3 ng/ml.
In 2 further patients with CAH (SE and WA) basal levels of FSH were higher than in the other patients suffering from this disease. The secretory H were response of FSH in these 2 patients, as well as in one patient with idiopathic ecretory hirsutism and 2 patients with adrenocortical carcinoma was, however, similar opathic to that observed in the other patients with CAH, as the main share of FSH similar was secreted during period II (Table 3). of FSH
During administration of dexamethasone (0.5 mg po, q. i. d. for at least 3 days) plasma levels of adrenal androgens were suppressed in patients with least 3 ts with CAH. A decrease of DHEA and AND was observed in one patient with idio- pathic hirsutism, while plasma levels of adrenal androgens remained unchanged th idio- in one patient with adrenocortical carcinoma (Table 1). changed
Serum levels of LH and FSH in patients pre-treated with dexamethasone prior to and during the administration of the LH-RH-analogue are shown in
thasone Table 4. Basal levels of LH and FSH in the 5 patients with CAH, where com- 1own in plete evaluation was possible, plus those of patient DR, who had to be excluded e com- from further statistical evaluation due to incomplete sampling, were 1.63 ± 0.19 xcluded and 1.96 ± 0.15 ng/ml, respectively. These values are in the same range as ± 0.19 those obtained prior to dexamethasone. The total response upon the LH-RH- ange as analogue in the 5 patients with CAH pre-treated with dexamethasone, who - H-RH- were included into statistical evaluation was 66.1 ± 8.9 ng/ml (without dexa- e, who methasone: 91.1 + 25.9 ng/ml, N. S.), whereas total response of FSH was t dexa- 44.8 ± 4.7 ng/ml (without dexamethasone: 49.2 ± 8.7 ng/ml, N. S.). The greater $H was share of LH and FSH in patients with CAH during treatment with dexame- greater thasone was secreted in period II (LH: 40.9 + 5.0 vs. 31.8 + 5.6 ng/ml during
exame- period I, N. S .; FSH: 32.7 ± 4.8 vs. 11.3 ± 1.7 ng/ml, P < 0.05).
during
In the remaining 2 patients with CAH (SE and WA) and in one patient with idiopathic hirsutism the total response of LH and FSH upon the LH-RH- patient analogue was decreased during treatment with dexamethasone in comparison H-RH- with basal conditions. In one patient with adrenocortical carcinoma (MH) how- parison ever, the release of LH and FSH upon the LH-RH-analogue was greater during 1)
how- treatment with dexamethasone. With the exception of patient SE, who pre- during sented with a greater response of LH during period I, the release of LH and 10 pre- FSH was greater in period II than in period I in all patients during treatment _H and with dexamethasone (Table 4). atment
| LH | FSH | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Patient | CAH (n = 5) (x ± SE) | DR | SE | WA | BE | MH | CAH (n = 5) (x ± SE) | DR | SE | WA | BE | MH |
| Diagnosis | (CAH) | (CAH) | (CAH) | (IH) | (AC) | (CAH) | (CAH) | (CAH) | (IH) | (AC) | ||
| -15 | 2.48 | 7.11 | 2.37 | 2.87 | 2.31 | 2.43 | 21.03 | 1.70 | 2.38 | 2.22 | ||
| 0 | 2.48 | 7.30 | 2.00 | 2.85 | 2.31 | 2.16 | 20.46 | 1.70 | 2.39 | 2.53 | ||
| x | 1.45 ± 0.11 | 1.89 ± 0.16 | ||||||||||
| Period I | ||||||||||||
| 10 | 5.45 ± 0.39 | 3.30 | 12.75 | 10.08 | 3.81 | 3.76 | 2.99 ± 0.21 | 2.60 | 21.20 | 2.48 | 2.53 | 3.32 |
| 20 | 8.87 ± 1.35 | 2.97 | 18.95 | 16.55 | 5.04 | 5.16 | 4.34 ± 0.30 | 3.41 | 20.45 | 3.20 | 2.91 | 4.47 |
| 30 | 11.14 ± 2.03 | 4.18 | 24.55 | 19.30 | 8.65 | 5.65 | 5.17 ± 0.48 | 3.69 | 25.25 | 3.65 | 2.97 | 4.90 |
| 60 | 12.00 ± 2.16 | * | 26.05 | 24.00 | 8.65 | 6.77 | 6.33 ± 0.61 | * | 26.95 | 4.29 | 3.08 | 6.15 |
| Period II | ||||||||||||
| 120 | 16.42 ± 2.85 | 48.51 | 24.50 | 44.55 | 22.05 | 11.49 | 10.48 ± 1.85 | 7.57 | 29.40 | 7.76 | 7.27 | 11.21 |
| 240 | 16.66 ± 1.54 | 31.79 | 20.55 | 42.40 | 22.65 | 10.82 | 12.12 ± 1.62 | * | 29.75 | 9.81 | 9.42 | 12.64 |
| 360 | 9.02 ± 1.11 | 34.21 | 12.10 | 23.00 | 12.05 | 5.90 | 9.84 ± 1.02 | 9.42 | 17.80 | 9.08 | 7.19 | 9.06 |
| 480 | 4.99 ± 0.66 | 23.43 | 13.10 | 13.10 | 8.10 | 2.86 | 7.80 ± 0.70 | 7.22 | 25.35 | 6.42 | 4.96 | 6.73 |
| 1440 | 1.44 ± 0.14 | 3.64 | 7.90 | 4.15 | 3.05 | 1.71 | 2.76 ± 0.26 | 3.31 | 17.51 | 2.94 | 2.81 | 2.29 |
* No sample obtained.
Plasma levels of testosterone in 3 patients with CAH (BM, BA and BR) had been 304, 215 and 457 ng/100 ml in the basal state and 32, 32 and 24 ng/100 ml during treatment with dexamethasone. During continued treatment with dexa- methasone these patients presented with plasma levels of testosterone of 289, 364 and 548 ng/100 ml 7 days after the im administration of 100 mg testo- sterone propionate and 250 mg testosterone oenanthate. Corresponding plasma levels of DHEA and AND 7 days after im testosterone were 12, 21, 24 and 18, 296, 29 ng/100 ml, respectively. The secretory response of LH and FSH upon iv LH-RH-analogue was unchanged in these patients 7 days after im testosterone when compared with the response during treatment with dexame- thasone alone.
DISCUSSION
Upon the administration of luteinizing hormone-releasing hormone (LH-RH) normal male and female subjects during the follicular phase of the menstrual cycle present with a qualitatively and quantitatively identical rise in plasma concentrations of LH and FSH (Besser et al. 1972), although the response of both hormones varies with age (Garnier et al. 1974) and is greater during the luteal phase (Yen et al. 1974; Jewelewicz et al. 1977; Dericks-Tan et al. 1977). D-Ser(TBU)6-EA10-LH-RH, an analogue of LH-RH (König et al. 1975), provokes a prolonged stimulation of gonadotrophin-secretion in normal male (Wiegelmann et al. 1976; Vierhapper et al. 1977) and female subjects (Friedrich et al. 1978) when compared with equimolar doses of LH-RH.
When comparing the response of LH between 0 and 60 min with that seen between 120 and 480 min after the administration of this LH-RH-analogue it is apparent that the greater share of LH was secreted during the first period in male subjects and during the second period in females, whereas the main secretory response of FSH occurred in the second period in both males and females. The total response of both gonadotrophins upon the LH-RH-analogue was larger in females than in males (Fig. 1).
As two pools of LH have been demonstrated in both male and female sub- jects (Bremner & Paulsen 1974; Hoff et al. 1977) a possible explanation for this different pattern of LH-secretion could be a larger second pool and/or a more pronounced de novo synthesis of LH in females. Considering the pitoval role of sex-steroids in the control of gonadotrophins (Moore & Price 1932), either a lack of oestrogens and/or gestagens in males, or a lack of androgens in females may be the cause of this phenomenon. To evaluate the latter pos- sibility we have studied the effect of the LH-RH-analogue upon the secretion of LH and FSH in female patients with either connatally or acquired elevation of adrenal androgens.
130
ng/ml
130
ng/ml
120
120
110
Z LH (SUM OF INCREMENTS ABOVE BASAL LEVELS )
110
FSH ( SUM OF INCREMENTS ABOVE BASAL LEVELS)
HEALTHY MALES
100
100
HEALTHY FEMALES
90
CAH (46 XX)
90
80
CAH ( 46 XX ) DURING
80
DEXAMETHASONE
70
70
60
60
50
T
50
T
I
40
40
T
30
30
20
20
T
10
10
T
L
T
0
0-00
120 -480
0-1440 MINUTES
0
0-60
120 - 480
0 - 1440 MINUTES
*
*
**
22
*
*
×
*
Fig. 1. Mean sum of increments above levels of LH (ng/ml, x ± SE) and FSH (ng/ml, & ± SE) after the administration of the LH-RH-analogue (10 µg iv) in healthy males (N = 5), healthy females (N = 5) and in patients with CAH (46 XX. N = 5) prior to and during treatment with dexamethasone. # P< 0.05. ** P < 0.005. *** P < 0.0005.
An inhibition of the LH-RH-induced secretion of LH by androgens has been shown in vitro (Schally et al. 1973; Tang 1978), whereas both stimulatory (Krause 1976) and inhibitory (Debeljuk et al. 1972; Cheung & Davidson 1977) effects of testosterone have been observed in vivo in male and female rats. An increase of LH-RH-induced gonadotrophin-secretion after pre-treatment with dihydrotestosterone has been reported in males (D’Agata et al. 1975). The ef- fectiveness of elevated testosterone levels in suppressing basal and LH-RH- stimulated secretion of gonadotrophins in males is however, well documented (Lee et al. 1972; Sherins & Loriaux 1973; von zur Mühlen & Köbberling 1973). Untreated female children with congenital adrenal hyperplasia show a very weak response to LH-RH (Job et al. 1977). On the other hand, normal levels of adrenal androgens are only of minor importance for the control of gonado- trophic function (Verjans & Eik-Nes 1975) and a dynamic reserve of pituitary LH and FSH appropriate for skeletal age and sex has been demonstrated in adequately glucocorticoid-substituted patients with CAH (Reiter et al. 1975; Wentz et al. 1976; Klingensmith et al. 1976; Cacciari et al. 1976). Thus, in female patients with CAH, neonatal exposure to high levels of androgens does
not, as in the rat (Pfeiffer 1936; Barraclough 1966; Moguilevsky et al. 1977) imprint a pattern of gonadotrophin-release which is permanently different from that seen in normal females.
Unlike the patients reported by Reiter et al. (1975), 5 out of 8 females with CAH presented in this study were amenorrhoeic in spite of previous therapy. Their basal plasma levels of androstenedione, dehydroepiandrosterone and tes- tosterone were well above those of normal females due to withdrawal of gluco- corticoid-therapy at least 3 days prior to the first administration of the LH- RH-analogue. A pattern of LH-secretion upon the LH-RH-analogue which was qualitatively similar to that seen in normal females albeit slightly smaller, which was, however, found even in the patients with CAH who were younger than haller, than normal controls. Thus, even unsatisfactory previous therapy in our patients did not prevent a regular response of LH and FSH upon the LH-RH-analogue. ’s did This is not necessarily in contradiction with the results of Klingensmith et al. ogue. (1976), as the time interval between the withdrawal of glucocorticoids and the et al. administration of the LH-RH-analogue was comparatively small in our pa- id the tients, and testosterone-induced inhibition of the response upon LH-RH is r pa- occurring slowly (Camino-Torres et al. 1977).
1977) from with rapy. d tes- ¡luco- LH-
Yet, basal levels of gonadotrophins in untreated patients with CAH were lower than in normal females except for 2 patients (WA and SE) aged 33 and were 50 years. The reason for the elevated levels of LH and FSH in these older 3 and patients in the presence of increased levels of adrenal androgens in not clear older as yet. The response of LH upon the LH-RH-analogue seen in these 2 patients clear as well as in one patient with idiopathic hirsutism and 2 patients with adreno- tients cortical carcinoma was, however, qualitatively similar to that seen in healthy reno- females and different from that seen in healthy males. ealthy
RH is
The response of FSH upon LH-RH in CAH has been reported to be larger (Reiter et al. 1975) and smaller (Cacciari et al. 1976) than normal. In our larger patients we observed no differences of FSH-secretion upon the LH-RH-ana- n our logue in comparison to healthy females; due to heterogenity of age in this ana- group quantitative results have, however, to be interpreted with caution. 1 this
Thus, the large second pool of LH in female subjects appears to be un- altered by elevated levels of adrenal steroids such as androstenedione, dehydro- e un- epiandrosterone and testosterone. Most likely, this observation could include ydro- 17-hydroxyprogesterone, although plasma levels of this steroid have not been iclude determined in this study. been
Serum levels of androgens and the response of LH and FSH upon the LH- RH-analogue were unchanged in one patient with adrenocortical carcinoma : LH- during treatment with dexamethasone, whereas patients with CAH presented inoma with suppressed adrenal androgens. The response of LH and FSH upon the ;ented LH-RH-analogue was qualitatively unchanged in this group, although the re- In the lease of LH was slightly diminished in 6 out of 8 patients with CAH. Two ne re-
Two
patients with CAH however, presented with a larger secretion of LH upon the LH-RH-analogue during treatment with dexamethasone.
Although testosterone is essential for the maintenance of hypothalamic LH- RH-content (Shin & Howitt 1976), androgens decrease responsiveness upon exo- genous LH-RH by acting both on the hypothalamic and pituitary level (Cheung & Davidson 1977). If dexamethasone would influence the response of LH upon the LH-RH-analogue by inhibition of adrenal androgen production, an increase rather than a decrease of LH-RH-induced LH-secretion would be expected. Thus the fall in LH-release observed in most patients with CAH is more likely due to a direct inhibitory action of dexamethasone upon the pituitary (Baldwin & Sawyer 1974) and/or the hypothalamus (Sakakura et al. 1975). This is also in accordance with results obtained in Cushing’s disease (Boccuzzi et al. 1975).
The concept, that dexamethasone is effective rather by a direct action upon the pituitary and not by inhibition of adrenal androgen production is also in accordance with the results obtained in 3 patients with CAH 7 days after im testosterone during continued treatment with dexamethasone. Suppression of adrenal androgens plus substitution of testosterone simulates, in genetic females with CAH, a pattern of sex-steroids even more similar to that of normal males than during basal conditions. Response of LH and FSH upon the LH-RH- analogue obtained under these conditions were however, identical with those during dexamethasone alone.
In conclusion, our results indicate that the less pronounced secretion of LH in healthy males in comparison to healthy females 120-480 min after admini- stration of the LH-RH-analogue does not seem to be due to higher prevailing levels of androgens. The examination of male subjects suffering from endo- genous overproduction of oestrogens may be helpful to further elucidate this sexual difference.
ACKNOWLEDGMENTS
The skilled technical help of Mrs. E. Nowotny is grateful acknowledged. Supported by the ‘Fonds zur Förderung der wissenschaftlichen Forschung Österreichs’, Förderungs- nummer M2 - 2777).
REFERENCES
Baldwin D. M. & Sawyer C. H .. Endocrinology 94 (1974) 1397.
Barraclough C. A .: Recent Progr. Hormone Res. 22 (1966) 503.
Besser G. M., McNeilly A. S., Anderson D. C., Marshall J. C., Harsoulis P., Hall R., Ormston B. J., Alexander L. & Collins W. P .: Brit. med. J. 3 (1972) 267.
Boccuzzi G., Angeli A., Bisbocci D .. Fronzo D., Gaidano G. P. & Ceresa F .: J. clin. Endocr. 40 (1975) 892.
Bremner W. J. & Paulsen C. A .: J. clin. Endocr. 39 (1974) 302.
Cacciari E., Cicognani A., Pirazzoli P., Tassoni P., Zappulla F., Salardi S., Benardi F., Mazzanti L. & Vianelli P .: J. clin. Endocr. 43 (1976) 1146. aiardi F.,
Camino-Torres R., Ma L. & Snyder P. J .: J. clin. Endocr. 44 (1977) 1142.
Cheung C. Y. & Davidson J. M .: Endocrinology 100 (1977) 292.
D’ Agata R., Gulizia S., Andò S. & Polosa P .: Acta endocr. (Kbh.) 79 (1975) 1.
Debeljuk L., Arimura A. & Schally A. V .: Endocrinology 90 (1972) 1578.
Dericks-Tan J. S. E., Hammer E. & Taubert H .- D .: J. clin. Endocr. 45 (1977) 597.
Friedrich E., Etzrodt A., Becker H., Hanker J. P., Keller E., Kleist P., Pinto V., Schindler A. E., Schneider H. P. G., Vanderbeck O., Werder H. & Wyss H. I .: Acta to V., endocr. (Kbh.) 87 (1978) 19. L: Acta
Garnier P. E., Chaussain J .- L., Binet E., Schlumberger A. & Job J .- C .: Acta endocr. (Kbh.) 77 (1974) 422. a endocr.
Hoff J. D., Lasley R. L., Wang C. F. & Yen S. S. C .: J. clin. Endocr 44 (1977) 302. ) 302.
Jewelewicz R., Dyrenfurth I., Ferrin M., Bogumil J. & Vande Wiele R. L .: J. clin. Endocr. 45 (1977) 662. clin.
Job J .- C., Chaussain J .- C. & Garnier P. E .: Hormone Res. 8 (1977) 171.
Klingensmith G. J., Wentz A. C., Meyer W. J. & Migeon C. J .: J. clin. Endocr. 43 (1976) 933. ndocr.
König W., Sandow J. & Geiger R .: Peptides: Chemistry Structure and Biology, Ann Arbor Science Publ. Inc. (1975) p. 883.
Ann
Krause W .: Endokrinologie 68 (1976) 267.
Lee P. S., Jaffe R. B., Midgley A. R., Kohen F. & Nieswender G. D .: J. clin. Endocr. 35 (1972) 636. Endocr.
Luyten J. A. & Rutten G. A. F. M .: J. Chromatog. 91 (1974) 393.
Moguilevsky J. A., Scacchi P. & Rubinstein L .: J. Endocr. 74 (1977) 143.
Moore C. & Price D .: Amer. J. Anat. 50 (1932) 13.
von zur Mühlen A. & Köbberling J .: Metab. Res. 5 (1973) 266.
Pfaffenberger C. D. & Horning E. C .: J. Chromatog. 112 (1975) 581.
Pfeiffer C. A .: Amer. J. Anat. 58 (1936) 195.
Prader A .: Helv. paediat. Acta 9 (1954) 231.
Reiter E. O., Grumbach M. M., Kaplan S. L. & Conte F. A .: J. clin. Endocr. 40 (1975) 318.
Sakakura M., Takebe K. & Nakagawa S .: J. clin. Endocr. 40 (1975) 774.
975) 318.
Schally A. V., Redding T. W. & Arimura A .: Endocrinology 93 (1973) 893.
Sherins R. J. & Loriaux D. L .: J. clin. Endocr. 36 (1973) 886.
Shin S. H. & Howitt C. J .: Neuroendocrinology 21 (1976) 165.
Tang L. K. L .: Amer. J. Physol. 235 (1978) E 291.
Verjans H. L. & Eik-Nes K. B .:: Acta endocr. (Kbh.) 81 (1975) 198.
Vierhapper H., Waldhäusl W. & Torres J .: Acta endocr. (Kbh.) Suppl. 208 (1977) 34 (Abstract). ) 34
Waldhausl W., Herkner K., Nowotny P. & Bratusch-Marrain P .: J. clin. Endocr. 46 (1978) 236. docr. 46
Wentz A. C., Garcia S. C., Klingensmith G. J., Migeon C. J. & Jones G. S .: J. clin. Endocr. 42 (1976) 239. .: J. clin.
Wiegelmann W., Solbach H. G., Kley H. K., Nieschlag E., Rudorff K. H. & Se Krüskemper H. L .: Hormone Res. 7 (1976) 1.
Yen S. C. C., VandenBerg G., Reber R. & Ehara Y .: J. clin. Endocr. 39 (1974) 811. 811.
Received on February 2nd, 1979.