Hypothalamic-pituitary-gonadal axis in major depressive disorders

Depression and Its Effect on the Menstrual Cycle

A strong association is noted between depression and early perimenopause as well as menopause. The association was found to be the greatest in women with natural menopause at the age less than 40 years. Excessive corticotropin-releasing hormone (CRH) levels in depression lead to inhibition of the hypothalamic-pituitary-gonadal (HPG) axis and increased cortisol levels which further inhibits the action of gonadotropin-releasing hormone (GnRH) neurons, gonadotrophs, and gonads. The resulting changes in luteinizing hormone (LH) amplitude, follicle-stimulating hormone (FSH) levels, and LH pulse frequency were noted in patients with depression.

Besides depression, earlier surgical menopause is associated with cognitive decline. In addition, it is seen that menopausal changes predisposed females to an increased risk of depression. The association between dysmenorrhea and depression was found to be bidirectional and congruent in most studies. Patients with dysmenorrhea and coexisting depression had enhanced pain perception along with a poor response to pain relief measures. Even the treatment of underlying depression has been shown to cause menorrhagia. On the other hand, amenorrhea has also been reported as a side effect of sertraline and electroconvulsive therapy. Menstrual disorders contribute to a significant number of outpatient gynecological visits per year in the United States. Co-existing or history of depression can either be the cause of or interfere in the treatment of these disorders. Furthermore, the treatment of depression can be the etiology of various menstrual abnormalities, while menstrual disorders themselves could be the cause of depression. The increasing prevalence of depression, women’s health, multiple female-specific subtypes, and the preexisting burden of menstrual disorders necessitates more detailed studies on the effects of depression on the menstrual cycle. 

The effect of testosterone supplementation on depression symptoms in hypogonadal men from the Testim Registry in the US (TRiUS)

OBJECTIVE

To determine the effect of long-term testosterone replacement therapy (TRT) on depression symptoms in hypogonadal men.

METHODS

Data were from TRiUS, a multicenter, 12-month observational registry (N = 849) of hypogonadal men prescribed 1% testosterone gel. Measures including total testosterone (TT) were assessed at baseline and months 3, 6, and 12. Depression symptoms were measured with Patient Health Questionnaire-9 (PHQ-9), a validated self-report questionnaire. A PHQ-9 score decrease of ≥5 represents clinical improvement.

RESULTS

PHQ-9 scores were available for 762/849 TRiUS participants at baseline. Overall, 92.4% (704/762) demonstrated some level of depressive symptoms, with 17.3% (132/762) having moderately severe (score 15-19) to severe (score 20-27) symptoms. Subcohorts with significantly (p ≤ 0.03) more moderately severe to severe symptoms were: <60 years old, TT levels <250 ng/dl (<8.68 nmol/l), HIV/AIDS-positive, or used antidepressants or opioids. TT levels and PHQ-9 scores improved significantly (p < 0.01) by 3 months of TRT. At 12 months PHQ-9 scores showed a clinically meaningful mean improvement of 5.62 points, patients with moderately severe to severe symptoms decreased from 17.3% to 2.1% (5/233), and subcohorts, including those defined by age (<60 years) and antidepressant use, had improved PHQ-9 scores ≥5.

CONCLUSION

TRT may reduce depression symptoms in hypogonadal men, including middle-aged men and those using antidepressants.

Is there a neuroendocrinological rationale for testosterone as a therapeutic option in depression?

Depression is a disease of growing incidence and economic burden worldwide. In view of increasing treatment resistance, new therapeutic approaches are urgently needed. In addition to its gonadal functions, testosterone has many effects on the central nervous system. An association between testosterone levels and depressive symptoms has been proposed. Many hormones and neurotransmitters are involved in the aetiology and the course of depression including serotonin, dopamine, noradrenaline, vasopressin and cortisol. Testosterone is known to interact with them. Preclinical data suggest that testosterone has antidepressant potential. However, the data from clinical studies have been inconsistent. This review provides a critical overview on the currently available preclinical and clinical literature and concludes with clinical recommendations.

Testosterone and depression: systematic review and meta-analysis

BACKGROUND

Studies suggest that testosterone (TT) replacement may have an antidepressant effect in depressed patients.

OBJECTIVE

The objective of this study was to explore the effect of TT administration on depression using both a systematic review of the literature and a meta-analysis.

METHODOLOGY

A search was conducted of MEDLINE, the Clinical Trials Registry, and Cochrane Central for English-language publications concerning randomized, placebo-controlled trials involving use of TT therapy in depressed patients. We searched for additional trials in the individual reference lists of the articles identified in the search. A study was judged to be relevant for inclusion in this review and meta-analysis if it reported original data from a controlled trial comparing use of TT and placebo in patients diagnosed with a depressive disorder according to DSM criteria, and the treatment response was evaluated according to changes on the Hamilton Rating Scale for Depression (HAM-D). We extracted the following data from the identified studies: study source, total number of participants in the study and in each treatment group, participants' ages, number of participants with a diagnosis of hypogonadism or HIV/AIDS, study duration, type of intervention, and change in HAM-D scores in the groups receiving TT versus placebo. The meta-analysis evaluated the effect of TT replacement on response in depressed patients as measured by change in HAM-D scores in the available placebo-controlled, randomized clinical trails.

RESULTS

Seven studies (N=364) were identified that included a placebo-control group in a double-blind design. Eligibility criteria were clearly reported in all trials. Meta-analysis of the data from these seven studies showed a significant positive effect of TT therapy on HAM-D response in depressed patients when compared with placebo (z=4.04, P<0.0001). Subgroup analysis also showed a significant response in the subpopulations with hypogonadism (z=3.84, P=0.0001) and HIV/AIDS (z=3.33, P=0.0009) as well as in patients treated with TT gel (z=2.32, P=0.02).

CONCLUSIONS

TT may have an antidepressant effect in depressed patients, especially those with hypogonadism or HIV/AIDS and elderly subpopulations. The route by which TT is administered may play a role in treatment response.

Improvement of erectile function with Prelox: a randomized, double-blind, placebo-controlled, crossover trial

In a randomly allocated, double-blind, placebo-controlled, crossover design, 50 patients with mild to moderate erectile dysfunction (ED) were treated for 1 month with placebo or a combination of L-arginine aspartate and Pycnogenol (Prelox). Patients reported sexual function from diaries. Testosterone levels and endothelial NO synthase (e-NOS) were monitored along with routine clinical chemistry. Intake of Pycnogenol for 1 month restored erectile function to normal. Intercourse frequency doubled. e-NOS in spermatozoa and testosterone levels in blood increased significantly. Cholesterol levels and blood pressure were lowered. No unwanted effects were reported. Prelox is a promising alternative to treat mild to moderate ED.

The combined T3/TRH test in depressed patients and healthy controls

It is well established that depressed patients show a blunted TSH response in the TRH-stimulation test. However, it has not been investigated so far whether pre-treatment with 3,5,3'-triiodothyronine (T3) is able to further suppress the TRH-induced TSH response in depressed patients or whether it may cause an escape-phenomenon with paradoxically enhanced TSH stimulation in a subsequent TRH test. In 20 drug-free depressed patients (eight men, 12 women) suffering from a major depressive episode according to DSM-IV criteria and in 20 age- and sex-matched healthy controls, the single TRH-stimulation test (administration of 200 microg TRH at 09:00 h) was carried out followed by a combined T3/TRH test (pre-treatment with 40 microg T3 at 23:00 h the night before; administration of 200 microg TRH at 09:00 h the next day). Compared to the controls, the depressed patients showed a significantly blunted TSH response in the single TRH test. However, the percentage suppression of TRH-induced TSH stimulation after pre-treatment with 40 microg T3 was comparable in the depressive patients (61.07%) and the healthy volunteers (64.20%). Prolactin secretion did not differ between patients and controls either in the single TRH test or in the combined T3/TRH test. Apparently, in contrast to the hypothalamo-pituitary-adrenocortical (HPA) system, no disturbance of feedback control in regulation of the hypothalamo-pituitary-thyroid (HPT) axis secretion can be demonstrated in depressed patients when using the combined T3/TRH test.

Diurnal rhythms of free estradiol and cortisol during the normal menstrual cycle in women with major depression

To investigate whether depression is accompanied by changes in diurnal rhythms of free estradiol and cortisol in different phases of the menstrual cycle, we measured these two hormone levels in saliva samples collected every 2 h for 24 h from 15 healthy normally cycling women and 12 age-matched normally cycling women suffering from major depression taking antidepressants. The assessments were repeated four times over one menstrual cycle: during menstruation and in the late follicular/peri-ovulating, early to mid-luteal and late luteal phases, respectively. Quantification with a nonlinear periodic regression model revealed distinct diurnal rhythms in free estradiol and free cortisol in all subjects. For the diurnal cortisol rhythm, significant differences were found in the peak-width and ultradian amplitude among different menstrual phases, both in controls and depressed patients, while no significant differences were found between the two groups. The diurnal estradiol rhythm, on the other hand, was quite consistent among different menstrual phases within both groups, while the depressed patients had overall larger amplitudes than controls, which is negatively correlated with disease duration. Significant positive correlations between the two hormone rhythms were found for 24-h mean level (mesor), peak, and trough in late luteal phase, and for ultradian harmonics in early to mid-luteal phase in controls, but only for ultradian harmonics in late follicular/peri-ovulating phase and for acrophase in the menstruation phase in depressed patients. A sub-analysis was also performed in patients who received Fluoxetine (n = 7). The findings implicate a close correlation between the hypothalamic-pituitary-adrenal axis and the hypothalamic-pituitary-gonadal axis, both of which may be involved in depression.

Possible Relationship Between Testosterone and Comorbid Major Depressive Episode in Male Patients With Schizophrenia Treated With Typical Antipsychotic Medications

In this cross-sectional study, the author tested the hypothesis that serum testosterone levels were associated with depressive illness in chronic male schizophrenia patients. The subjects were 49 male inpatients meeting DSM-IV criteria for schizophrenia treated with typical antipsychotic medications. The author found that the schizophrenia patients with major depressive episodes (MDE) had been taking significantly higher dosages of antipsychotic medications than those without an MDE. Also, there was a trend for the serum testosterone concentration to be lower in schizophrenia patients with an MDE. It is suggested that we should be aware of testosterone levels when we find depression in chronic male schizophrenia patients, especially those treated with high-dose typical antipsychotic medications.

Andropause and psychopathology: minor symptoms rather than pathological ones

This study examined the psychological symptomatology of men diagnosed with andropause and the association between calculated free testosterone (T) and depressed mood, anxiety and quality of life. Subjects were 153 men, aged 50-70 years, who participated in a screening of andropause. Total testosterone, FSH, LH and SHBG levels were measured. Depressed mood was assessed with the Carroll Rating Scale, anxiety with the "anxiety-insomnia" dimension of the General Health Questionnaire, and quality of life with the World Health Organisation Quality of Life questionnaire. The results showed that levels of free T decreased with age, whereas FSH and LH increased. Carroll Rating Scale scores were higher among hypogonadal subjects, but the mean score was low and not pathological. A negative correlation was observed between severity of depression as assessed by the Carroll Rating Scale and free T levels. However, subjects with a significant score on this scale did not exhibit different free T levels compared to subjects with a non-significant depressive score. Anxiety and quality of life did not differ between hypogonadal and eugonadal subjects. The present study therefore suggests that andropause is not characterised by specific psychological symptoms, but may be associated with "depressive symptoms" that are not considered as pathological.

Effects of androgen replacement on metabolism and physical performances in male hypogonadism

Hypogonadism in men is associated with decreased physical performance. This phenomenon depends on significantly measurable adverse traits in body composition, namely increased body fat content and reduced muscle mass. Physical abilities in hypogonadal men are further hampered by lower oxygen supply due to decreased hemoglobin concentrations and by poor glucose utilization. In addition, dysthymia and lack of necessary aggressiveness contribute to further deterioration of physical features. T substitution can improve lipid and insulin metabolism, resuiting in changes of body composition, such as decreasing fat depots. Growth of muscle fibers can also be observed. Stabilization of the musculo-skeletal system by increased bone density will further contribute to increased physical fitness, reflected by increased strength and endurance. Treatment outcome is strongly influenced by age and training. The issues reviewed strongly support T treatment of hypogonadal men accompanied by regular monitoring.

No relationship between testosterone levels and depressive symptoms in aging men

We investigated the associations between depression and serum testosterone levels in the elderly. There was no significant difference in the mean levels of the serum testosterone between the groups of patients and normals. For both groups, there was no significant correlation between testosterone and total depression scores or age.

The hypothalamic-pituitary-gonadal axis in mood disorders

This article has demonstrated that stress and HPA axis activation affect the reproductive axis. Despite similarities in the HPA axis picture between women with major depression and those with hypothalamic amenorrhea and exercise or nutritional amenorrhea, no abnormalities in LH secretion have been documented in major depression. Lower estradiol in the follicular phase in depressed women and lower testosterone in depressed men however, have been observed [81, 92]. Although PMS would appear to be the best candidate for a mood disorder associated with abnormalities in reproductive hormones, no abnormalities in LH, estradiol or progesterone have been documented in PMS either [62]. Similarly, blockade of progesterone appears to be ineffective as a treatment for PMS [79]. Complete elimination of monthly cycling with leuprolide improves mood, however. No published studies have examined women with major depression to determine whether leuprolide will exacerbate or improve depressive symptoms. Some studies suggest beneficial effects of estrogen on mood in postmenopausal women, but no placebo controlled studies have explored estrogen augmentation in the treatment of major depression in either post- or premenopausal women, although estrogen is beneficial in women with perimenopause-related mood disorders [78].

Cushing’s disease and melancholia

Striking similarities exist in the endocrinology of Cushing's disease and melancholic depression.Laboratory abnormalities, which have been found in both, include raised urinary,plasma and salivary cortisol, non-suppression of cortisol in the dexamethasone suppression test and adrenocorticotrophin (ACTH) hypersecretion. The hypercortisolism can be so severe in melancholic depression that it is difficult to distinguish from Cushing's disease and has been described as a "pseudo-Cushing's" state. Cerebrospinal fluid corticotrophin-releasing hormone (CRH) levels have been found to be lower in patients with Cushing's disease than in depressed subjects. Dynamic endocrine tests may help to distinguish between the two disorders.An exaggerated response to synacthen has been found in both but a reduced ACTH response to CRH occurs in depression, unlike those with Cushing's disease who show ACTH hyper-responsiveness. Other tests, which may help to distinguish between the two disorders,include the dexamethasone-CRH test, the naloxone test, the insulin-induced hypoglycemia test and the desmopressin stimulation test. Similarities in psychiatric symptoms have been recognised for many years. More recently, the physical complications of melancholic depression have been noted. These include osteoporosis, an increased risk of death from cardiovascular disease, hypertension, a redistribution of fat to intra abdominal sites and insulin resistance. Cushing's disease shares these physical complications and we propose that the common underlying factor is excessive plasma glucocorticoids. The increasing recognition of the physical complications and the increased morbidity and mortality in those who suffer from depression underscores the necessity for early detection and treatment of this illness and screening for undetected physical complications.

The male menopause and mood: testosterone decline and depression in the aging male--is there a link?

The objective of this study was to review the literature on the hormonal changes that occur in aging males in order to determine if testosterone declines in relation to depressed mood and if testosterone might prove useful in treatment of depression. Pertinent articles were identified through a MEDLINE search from 1966 to 1999 and by careful review of the bibliographies of articles most relevant to the topic. There is a moderate decline of total testosterone and more significant decline of bioavailable testosterone in aging males. Elderly males who are depressed appear to have the lowest testosterone levels. In eugonadal males, testosterone replacement does not have a significant effect on mood; in hypogonadal males, some studies show an effect whereas others do not. In several small studies of depressed hypogonadal males, testosterone was effective in alleviating depression. Major side effects of testosterone include increased hematocrit and potential effects on the prostate and lipid metabolism. Testosterone replacement as primary or adjuvant treatment of depression may prove useful in elderly, hypogonadal males who fail to respond to conventional antidepressants. Further studies are needed to confirm these initial impressions.

Melancholic depression and abdominal fat distribution: a mini-review

Fat is stored around the abdomen in both subcutaneous and intra abdominal (visceral) sites. Visceral fat is associated in its own right with a set of metabolic abnormalities, including non insulin dependent diabetes, hypertension and dyslipidaemias. States of marked hypercortisolaemia, for example Cushing's syndrome, lead to the preferential accumulation of visceral fat. Since melancholic depression is known to be associated with elevated plasma Cortisol levels, this review explores whether depressed patients are prone to excess visceral fat storage, with the subsequent risk of developing the associated metabolic disturbances. Though the literature is limited, there is evidence that intra abdominal fat is increased in major depression. There is also evidence that depression is associated with increased risk of death from cardiovascular disease. Is visceral fat and its association with metabolic abnormalities the link between depression and physical illness?

Testosterone, gonadotropin, and cortisol secretion in male patients with major depression

OBJECTIVE

Previous studies of sex hormone concentrations in depression yielded inconsistent results. However, the activation of the hypothalamic-pituitary-adrenal system seen in depression may negatively affect gonadal function at every level of regulation. The objective of this study was to explore whether major depressive episodes are indeed associated with an alteration of gonadal function.

METHODS

Testosterone, pulsatile LH secretion, FSH, and cortisol were assessed using frequent sampling during a 24-hour period in 15 male inpatients with major depression of moderate to high severity and in 22 healthy comparison subjects (age range 22-85 years).

RESULTS

An analysis of covariance model showed that after adjustment for age only, daytime testosterone (p < .01), nighttime testosterone (p < .05), and 24-hour mean testosterone secretion (p < .01) were significantly lower in the depressed male inpatients. There was also a trend for a decreased LH pulse frequency in the depressed patients (p < .08).

CONCLUSIONS

Gonadal function may be disturbed in men with a depressive episode of moderate to high severity.

Psychoneuroendocrinology of depression. Hypothalamic-pituitary-gonadal axis

Women are more susceptible than men to depression, particularly during periods of rapid fluctuation of gonadal hormones, such as premenstrually, postpartum, and during the climacteric. This review summarizes the evidence for the association of depression with abnormalities in reproductive hormones. Although there are similarities in stress hormones changes between depressed women and women with stress-related amenorrhea, no abnormalities in LH activity have been documented in depression. Similarly no abnormalities in LH, estradiol, or progesterone have been documented in premenstrual syndrome (PMS), although complete elimination of monthly cycling with leuprolide improves mood. Some studies have suggested beneficial effects of estrogen on mood in postmenopausal women but as yet there have been no adequately controlled studies of estrogen treatment of either premenopausal or postmenopausal women.

Neuroendocrine aspects of primary endogenous depression--XIV. Gonadotropin secretion in female patients and their matched controls

To determine the extent of dysregulation of gonadotropin secretion in depressed women, we measured nocturnal and diurnal serum luteinizing hormone (LH) and follicle stimulating hormone (FSH) concentrations and the responses of these hormones to gonadotropin releasing hormone (LHRH) in 20 Research Diagnostic Criteria primary, definite endogenous female depressives and in 20 individually matched female normal controls. Fourteen patients and 14 controls were premenopausal, and six patients and six controls were peri/postmenopausal or panhysterectomized. None of the latter was receiving estrogen replacement therapy. The premenopausal patients showed no significant differences in basal nocturnal or diurnal gonadotropin concentrations and no significant differences in hormone concentrations post-LHRH compared to their premenopausal matched controls. In contrast, in the postmenopausal subjects there were (1) significantly increased diurnal vs. nocturnal serum FSH concentrations in the depressives; (2) marginally increased nocturnal, diurnal, and LHRH-stimulated LH concentrations and highly significantly increased LHRH-stimulated FSH concentrations in the depressives compared to their controls; and (3) positive correlations between the LH measures and ratings of depression severity in the patients. These results suggest a dysregulation of the HPG axis in peri/postmenopausal and panhysterectomized female endogenous depressives.

The Kallmann's syndrome variant (KSV) model of the schizophrenias

The KSV model of the schizophrenias proposes that up to 70% of schizophrenics have a pathogenic allele, or abnormal expression, of the KALIG-1 gene which is located at Xp22.3. This gene encodes a nerve-cell adhesion molecule (N-CAM) like protein, and is deleted in 66% of patients with Kallmann's syndrome, anosmia with secondary hypogonadism. Although superficially distinct, the schizophrenias and Kallmann's syndrome show numerous parallel trait defects which occur with a similar sex distribution. These defects are usually more profound in Kallmann's syndrome. Occasionally, Kallmann's patients exhibit additional defects, such as ichthyosis, which are due to the further deletion or translocation of adjacent genes. Since schizophrenics exhibit virtually all known trait defects in Kallmann's except these, it suggests that the aberrant genes are defective, but not deleted in schizophrenia. It also appears that compensatory mechanisms, involving serine proteases, are active in schizophrenia, which largely preserve fertility, but at the expense of an increased vulnerability to develop a psychosis by an episodic disruption of the blood-CSF barrier. Consequently, schizophrenia is rare in Kallmann's patients, while most schizophrenics are capable of reproduction.

Release of corticotropin after administration of corticotropin-releasing hormone in depressed patients in relation to the dexamethasone suppression test

The possible hypersecretion involvement of corticotropin-releasing hormone (CRH) in the pathophysiology of hypothalamic-pituitary-adrenocortical axis disturbances in patients with major depressive episode and with an abnormal dexamethasone suppression test (DST) was investigated. The corticotropin (ACTH) and cortisol response to the injection of 45 micrograms of synthetic human CRH at 1630 were analyzed in 24 inpatients with normal (suppressors) or abnormal (nonsuppressors) DST. The outcome of the DST was analyzed using 3 cut-off points for the cortisol levels. The clinical assessments included two rating scales. The results showed that nonsuppressors had a significantly lower ACTH response to CRH stimulation than suppressors at all cut-off points (calculated as net area under the curve and as the difference between the peak and the baseline level) despite no significant differences in the severity of depression.

Effects of hypothalamic peptides on the aging brain

The hypothalamic peptide hormones, TRH, LHRH (GnRH), CRH, GHRH, and GHIRH (somatostatin), influence the release of the anterior pituitary hormones, which in turn promote the release of target endocrine gland hormones and other metabolites. These latter compounds feed back to the brain to help control the secretion of the hypothalamic hormones. This is a dynamic interaction that is influenced by the aging process: Most of these hormones systems become less responsive with advancing age, due to decreased function of peptide-containing secretory neurons, a loss of hormone receptor sensitivity, and/or a reduction in the output of the target endocrine glands. That the hypothalamic peptides themselves can influence brain function is supported by the fact that most are found in areas of the brain other than the hypothalamus and that receptors for them exist in these other areas. For example, CRH is contained in a number of central neural systems that can influence behavior, including limbic areas, the hypothalamus, locus coeruleus, median raphé nuclei, and cortical interneurons. CRH has been shown to be anxiogenic in animal models, and its effect can be blocked by CRH receptor antagonists. CRH content in the locus coeruleus is particularly increased by stress and may influence norepinephrine neurotransmitter function in this structure. In aging there is a gradual reduction of the sensitivity of the brain to the negative feedback of corticosteroids, such that CRH secretion becomes somewhat increased under basal conditions. The behavioral effects of this change are unclear, however, as is the influence of stress-related activation of CRH, ACTH, and glucocorticoid secretion on behavior in the elderly. Other hypothalamic peptides have different patterns of change with aging, and some are markedly altered in pathological conditions; for example, in Alzheimer's disease the content of CRH and somatostatin in certain brain areas is decreased. However, whether the changes in hypothalamic peptides precede or follow the pathological behavioral changes, and how they participate in the changes, is still unclear.

Tonic and dynamic gonadotropin secretion in depressive and normothymic phases of affective disorders

Baseline follicle stimulating hormone (FSH) and luteinizing hormone (LH) plasma levels and their responses to luteinizing hormone releasing hormone (LHRH) stimulation were investigated in 72 patients who met Research Diagnostic Criteria for affective disorders and in 72 healthy volunteers. Fifty-six patients were examined during a depressive phase and 16 during a normothymic phase. LH-FSH basal levels were significantly lower in postmenopausal depressed and normothymic women than in controls. In fertile women and men, concentrations of the two gonadotropins were also lower in patients than in controls, but the phenomenon did not generally reach statistical significance. LHRH-induced LH rises were lower in postmenopausal and fertile depressed and normothymic women than in controls, while FSH rises were reduced only in postmenopausal depressive women in both depressed and normothymic phases. The impairment underlying the gonadotropin secretory deficiency remains to be elucidated.

Neuroendocrine aspects of primary endogenous depression VIII. Pituitary-gonadal axis activity in male patients and matched control subjects

To determine the extent of hypothalamo-pituitary-gonadal (HPG) axis dysfunction in endogenous depressed men, we measured nocturnal and diurnal serum luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone (T), and estradiol (E2) concentrations, and their responses to gonadotropin releasing hormone (LHRH) and dexamethasone administration, in 16 Research Diagnostic Criteria primary, definite endogenous male depressives and 16 individually matched male normal controls. Compared to their controls, the patients showed no differences in basal nocturnal or diurnal gonadotropin or gonadal steroid hormone concentrations, and no differences in hormone concentrations either post-LHRH or post-dexamethasone. Age was negatively correlated with baseline serum T in the patients but not in the controls, and it was modestly positively correlated with baseline serum LH in both groups of subjects. In the patients, the presence of DSM-III melancholia was modestly negatively correlated with baseline and post-LHRH concentrations of both LH and FSH and was positively correlated with baseline serum T, but it bore no relation to serum E2. None of the other subject characteristics or specific dimensions of depressive symptomatology were significantly related to the HPG axis measures. The HPG axis measures also were unrelated to pre- and post-dexamethasone cortisol concentrations in both groups of subjects. The results of this study suggest that, in contrast to the hypothalamo-pituitary-adrenal cortical and thyroid axis abnormalities frequently found in endogenous depressives, HPG axis function in male depressives is relatively normal.