Daytime plasma melatonin levels in male hypogonadism.

It has previously been shown that increased nocturnal melatonin (MT) secretion exists in male patients with hypogonadotropic hypogonadism. However, little is known about the effects of gonadotropin and testosterone (T) treatment on early morning plasma MT levels in male hypogonadism. Also, the impact of gonadal steroids on plasma MT levels is an open question. We, therefore, determined early morning plasma MT levels at the same hour before and 3 months after treatment in 21 patients with idiopathic hypogonadotropic hypogonadism (IHH), 10 patients with primary hypogonadism, and 11 male controls. Plasma FSH, LH, PRL, T, and estradiol levels were also determined before and 3 months after treatment. Patients with IHH were treated with hCG/human menopausal gonadotropin, whereas patients with primary hypogonadism received T treatment. Short term treatments did not achieve normal T levels, although significant increases in T were observed in both groups. Plasma MT levels were measured by a RIA with a sensitivity of 10.7 pmol/L. Mean plasma MT levels before treatment were significantly higher in IHH (41.8 +/- 24.4 pmol/L) compared with those in the controls (21.7 +/- 10.8 pmol/L; P < 0.05). However, a slight, but not significant, increase in MT (34.2 +/- 21.1 pmol/L) was found in primary hypogonadism. Mean MT levels did not change significantly 3 months after the initiation of gonadotropin (41.7 +/- 22.8 pmol/L) or T (28.4 +/- 12.6 pmol/L) treatment in either IHH or primary hypogonadism, although a tendency for MT to decrease was observed in both groups. No correlation was found between MT and circulating FSH, LH, PRL, and gonadal steroids either before or after therapy. We conclude that male patients with IHH have increased early morning MT levels, although the pathophysiological mechanism is not clear. Furthermore, our study demonstrated that mean plasma MT levels are not influenced by short term gonadotropin or T treatment in male hypogonadism, although a longer time effect of gonadotropins or T treatment may not be excluded. The lack of correlation between plasma MT and circulating gonadal steroids before and after treatment suggests that there is no classic feedback regulation between the pineal gland and the testes.

Effects of gonadotropin and testosterone treatments on Lipoprotein(a), high density lipoprotein particles, and other lipoprotein levels in male hypogonadism.

It is known that lipoprotein(a) [Lp(a) is an independent risk factor for developing atherosclerosis, whereas the LpA-I particle of high density lipoprotein (HDL) is an antiatherogenic factor. The effects of androgen replacement therapy on lipid and lipoproteins have previously been reported in male hypogonadism. However, no study reported the effect of gonadotropin or testosterone treatment on Lp(a), LpA-I, or LpA-I;A-II levels in make hypogonadism. We, therefore, determined Lp(a), LpA-I, LpA-I:A-II, and other lipoprotein levels before and 3 months after treatment in 22 patients with idiopathic hypogonadotropic hypogonadism (IHH) and in 9 patients with Klinefelter's syndrome. All patients had been previously untreated for androgen deficiency. Plasma FSH, LH, PRL, testosterone (T), estradiol, and dehydroepiandrosterone sulfate levels were also determined before and 3 months after treatment. Patients with IHH were treated with hCG/human menopausal gonadotropin, whereas patients with Klinefelter's syndrome received T treatment. Three months after treatment, mean T levels role to low normal levels in both groups. Triglyceride, LpA-I:A-II, Lp(a), HDL cholesterol, HDL3 cholesterol, and apolipoprotein (apo) A-I concentrations did not change significantly after treatment, whereas total cholesterol, low density lipoprotein cholesterol, LpA-I, and HDL2 concentrations were significantly increased 3 months after treatment in both groups. The apo B concentration significantly increased in patients with klinefelter's syndrome, whereas no change was observed in the IHH group. Lp(a) concentrations were not related to all hormonal and clinical parameters in both groups. LpA-I concentrations were significantly and negatively correlated with free T (r = -0.80; P = 0.010) in patients with Klinefelter's syndrome and were not correlated with all hormonal and clinical parameters in the IHH group. The LpA-I:A-II concentration was only correlated with body mass index (r = -0.83; P = 0.005) in patients with Klinefelter's syndrome, whereas it was correlated negatively with dehydroepiandrosterone sulfate (r = -0.57; P = 0.005) in the IHH group.2 Overall, our study demonstrates that gonadotropin or T treatment has a complex effect on lipids and lipoproteins. This complexity will be resolved when sufficient large scale androgen treatment data are available for assessment of the long term outcome of androgen treatment. The increases in total cholesterol and low density lipoprotein cholesterol concentrations after treatments are the adverse effects of these treatments, whereas the increases in HDL2 and LpA-I concentrations and the lack of changes in Lp(a) are the beneficial effects. Gonadotropin or T treatment did not modify the Lp(a) concentration, indicating that it is not affected by the hormonal milieu in male hypogonadism. Our study also showed that LpA-I, but not LpA-I:A-II, particles could be modified by androgen replacement therapy.

Central and peripheral neural responses in males with idiopathic hypogonadotropic hypogonadism.

It has previously been shown that abnormal neurophysiologic responses are associated with Kallmann's syndrome. However, little is known about neurophysiologic responses in idiopathic hypogonadotropic hypogonadism (IHH). Fifty-six untreated male patients with IHH (mean age: 20 +/- 0.7 years) were compared with a control group of 20 age-matched male subjects to determine whether IHH can lead to alterations in somatosensory evoked potentials (SSEPs) and brainstem auditory evoked potentials (BAEPs). We have also investigated the effect of gonadotropin replacement (hCG/hMG) therapy on these tests in 20 randomly selected patients. Significant cervical 7 (N13), Erb (N9) and thoracic 12 (N22) latency prolongation was observed in median and tibial nerve SSEPs in patients with IHH as compared with a matched control group. Other components of SSEPs and interpeak latencies of BAEPs yielded no significant difference between untreated patients and control group. Abnormal components of SSEPs did not correlate with basal hormone levels and did not improve with gonadotropin therapy. We conclude that IHH results abnormalities in peripheral but not central nervous system components of SSEPs and that short term gonadotropin treatment cannot correct these abnormalities.

Effects of gonadotropin and testosterone treatments on prostate volume and serum prostate specific antigen levels in male hypogonadism.

It is known that prostate specific antigen (PSA) is strongly androgen dependent, but little is known about the effects of gonadotropin and testosterone treatments on the prostate and serum PSA levels in male hypogonadism. We have therefore determined serum PSA levels before and 3 months after treatment in 13 patients with idiopathic hypogonadotropic hypogonadism (IHH) and 14 patients with Klinefelter's syndrome. Plasma FSH, LH, testosterone, PRL, testis and prostate volumes were also determined before and 3 months after treatments. Patients with IHH were treated with hCG/hMG and patients with Klinefelter's syndrome received testosterone treatment. PSA levels were determined by a kinetic enzyme immunoassay method. In patients with Klinefelter's syndrome FSH and LH levels were significantly decreased but total and free testosterone and PSA levels were significantly increased after 3 months of treatment. Right and left testicular volumes were not significantly changed whereas prostate volumes were significantly increased after treatment. In this group PSA levels were significantly and positively correlated with the prostate volume both before (r=0.54, P=0.048) and after treatment (r=0.61, P=0.012). In the IHH group total and free testosterone and PSA levels were significantly increased after gonadotropin treatment but FSH and LH levels did not change significantly. Right and left testicular volumes and the prostate volumes were also significantly increased after 3 months of gonadotropin treatment. In this group PSA levels were correlated with prostate volume before (r=0.74, P=0.004) treatment but not after therapy (r=0.35, P=NS). Our results show that serum PSA levels increase after gonadotropin and testosterone treatment in male hypogonadism, but this could not be used as an index for the evaluation of the androgen action in the treatment of male hypogonadism, since PSA levels following treatments were correlated with the prostate volume or T levels only in patients with Klinefelter's syndrome but not in the IHH group.