Effect of endothelin-1 in man--impact on basal and stimulated concentrations of luteinizing hormone, follicle-stimulating hormone, thyrotropin, growth hormone, corticotropin, and prolactin with and without pretreatment with nifedipine

In healthy men, intravenous (IV) endothelin-1 suppresses the growth hormone (GH)-releasing hormone (GHRH)-stimulated increase in GH and prolactin (PRL) and augments corticotropin (ACTH)-releasing factor (CRF)-stimulated secretion of ACTH. Since some actions of endothelin-1 on pituitary function in vitro are antagonized by calcium channel antagonists, we have studied the effect of pretreatment with oral nifedipine (10 mg, given before infusion of endothelin-1 or vehicle) on basal and stimulated concentrations of pituitary hormones in a group of healthy men (N = 6). The augmentative effect of endothelin-1 on CRF-induced ACTH secretion (P < .05) was counteracted by pretreatment with nifedipine. Pretreatment with nifedipine further inhibited (P < .01) the GHRH-induced increase in plasma concentrations of GH (P < .05), which, in keeping with previous data, had already been reduced by IV endothelin-1 alone (P < .05). Thus, both endothelin-1 and nifedipine influence pituitary hormone secretion in healthy man. However, nifedipine does not ubiquitously counteract the effects of endothelin-1 since it enhances some of its actions on the pituitary and diminishes others. Endothelin-1 may therefore influence pituitary function by mechanisms other than activation of calcium channels alone.

Anterior pituitary function in patients with newly diagnosed rheumatoid arthritis

Hormonal dysfunction involving the hypothalamic-pituitary-adrenal (HPA) axis, prolactin (PRL) secretion and sex hormone status has been supposed to contribute to the development or persistence of rheumatoid arthritis (RA). In addition, a reduced number of glucocorticoid receptors on circulating lymphocytes has been found in patients with RA. However, so far most studies have been performed in pre-treated patients. A combined test for total anterior pituitary reserve was performed in 10 patients with newly diagnosed untreated RA. Before and after stimulation with the respective hypothalamic releasing hormones, RA patients showed no difference in plasma concentrations of adrenocorticotrophic hormone (ACTH), cortisol, prolactin (PRL) and thyroid-stimulating hormone (TSH) when compared to healthy controls. In contrast, the growth hormone (GH) response to growth hormone-releasing hormone (GHRH) was blunted in RA patients. The hypothalamic-pituitary-thyroid/gonadal and adrenal axes seem to be unaltered in RA. However, if one considers the presence of chronic inflammation, normal plasma ACTH and cortisol concentrations must be considered as inappropriately low. The observed blunted GH release could be mediated by cytokines (e.g. IL-1), which are known to be elevated in RA.

Effects of terguride on anterior pituitary function in parkinsonian patients treated with L-dopa: a double-blind study versus placebo

In a randomized double-blind study, 20 parkinsonian patients (suffering from the disease for 2-18 years), chronically treated with levodopa (500-750 mg/day for 0.5-12 years), received terguride (1 mg b.i.d.) or placebo for 4 weeks. Growth hormone (GH), prolactin (PRL), thyroid-stimulating hormone (TSH), and insulin-like growth factor (IGF-I) secretions were studied before and after the morning dose of levodopa (250 mg p.o.), both before and at the end of study period. At the beginning of the study, basal hormonal levels were within normal limits, and levodopa administration induced a significant suppression in PRL and TSH levels (both p < 0.01)) and a significant increase in GH (p < 0.01). The same results were observed at the end of the study period in the placebo group. Addition of terguride induced a significant suppression in basal PRL levels (p < 0.01), whereas levodopa-induced hormonal changes were unaffected. These data suggest that the hypothalamic dopaminergic function that controls anterior pituitary hormones is preserved in parkinsonian patients, regardless of both the duration of the disease and the long-term treatment with levodopa. The strong additional prolactin-lowering effect of terguride indicates long-lasting dopaminergic effects, as is already known from hyperprolactinemic conditions. The dopaminergic effects of levodopa on TSH, GH, and IGF-I secretion were unchanged by terguride treatment. The anti-dopaminergic effects of terguride observed in the motor system in animal studies, as well as in levodopa-induced dyskinesias in parkinsonian patients, could not be observed in the case of the dopaminergic control of anterior pituitary hormones under the conditions of this study.

The effect of an opiate antagonist on the hormonal changes induced by hexarelin

OBJECTIVE

Growth hormone-releasing peptides (GHRPs) stimulate growth hormone (GH) release in vitro and in vivo in animals and in humans. GHRPs were developed by modification of the structure of met-enkephalin but GHRP-6 does not activate opiod receptors in animal studies. These agents may well have diagnostic and/or long-term therapeutic potential in the future so their effects on opiod receptors need to be clarified in humans as well. Hexarelin is a recently developed six amino acid residue GHRP.

DESIGN

We have investigated the effects of 100 micrograms/kg i.v. dose of the opiate antagonist naloxone and 2 micrograms/kg i.v. hexarelin or placebo on serum GH, prolactin, TSH, cortisol and plasma ACTH in 12 healthy volunteers in a double-blind, randomized trial.

RESULTS

Hexarelin significantly stimulated the peak serum levels and area under the curve for circulating GH and this effect was not modulated by naloxone. Hexarelin also caused significant elevation of circulating prolactin, cortisol and ACTH but did not influence circulating TSH levels. The effect of naloxone on cortisol and ACTH was stimulatory, while it did not influence prolactin, GH and TSH levels. The effect of the two drugs together on cortisol and ACTH was less than additive.

CONCLUSIONS

This study confirms that the activation of opiate receptors does not play a role in the GH-releasing effect of growth hormone-releasing peptides in humans.

Hormonal changes in male subjects over-ninety

The physiology of aging in very old people is still poorly understood. A wide variety of age-related factors confuse the interpretation of existing data, especially as regards the modifications of the endocrine system. The effect of age on the gonad-hypophyseal function was studied in 26 over ninety-year-old males and compared with a control aged between 27 and 88, subdivided into age groups. The serum levels of total testosterone were stable up to the ninth decade while they were lower in the over ninety-year-olds; free testosterone and its peripheral metabolites (estrogens and dehydrotestosterone) were also lower in the over ninety-year-olds with respect to the others, although the decrease had started more gradually at about the fourth decade. Sex-hormone-binding-globulin, the main serum carrier of testosterone, increased gradually with age. The levels of hypophyseal gonadotropins were constant up to the ninth decade where a significant and abrupt increase was observed. The data suggest the presence of marked alterations of the testicular-hypophyseal axis in the later decades of life, with important repercussions on the pattern of circulating sex steroids.

Antiestrogenic properties of raloxifene

This 21-day, open-label study evaluated the effects of raloxifene and tamoxifen on estrogen-induced changes in serum levels of anterior pituitary hormones (prolactin, luteinizing hormone, and follicle-stimulating hormone), sex steroids (testosterone, estradiol), and binding globulins [thyroid binding globulin (T3 resin uptake), transcortin, sex steroid binding globulin]. Seventeen healthy male volunteers completed the study after being randomized to one of three treatments: raloxifene, tamoxifen, or placebo. Six subjects received raloxifene (200 mg daily) for 10 days, 6 subjects received tamoxifen [20 mg twice a day (b.i.d.)] for 10 days, and 5 subjects received placebo for 10 days. All subjects received ethinyl estradiol (20 micrograms b.i.d.) for 7 days starting 3 days after initiation of study drug or placebo treatment. Results of the primary analysis of this study indicate that for six of the seven analyzable parameters of estrogen action (excluding luteinizing hormone) raloxifene blunted the estrogen response; this effect was significant only for T3 resin uptake. Tamoxifen administration significantly blunted or reversed the estrogen effect in all six of these parameters. Raloxifene, an effective antiestrogen in animal models, is also antiestrogenic in humans.

Isolated adrenocorticotropin deficiency as a rare cause of hypoglycaemia in children. Further studies and report of an additional case

An 11.5-year-old boy presented with recurrent attacks of hypoglycaemic coma. Endocrine investigations indicated adrenocortical insufficiency secondary to isolated ACTH deficiency, how ACTH and cortisol plasma levels with normal secretory reserve of other anterior pituitary hormones. The absence of ACTH response after corticotropin releasing factor and insulin-induced hypoglycaemia suggested a failure of primary pituitary ACTH-secreting cells. Among other hormone-secreting cells, pituitary cell circulating antibodies were negative. CT scan and MRI failed to reveal any anatomical abnormality of the sella or suprasellar area.

Prolonged intrathecal chemotherapy replacing cranial irradiation in high-risk acute lymphatic leukaemia: long-term follow up with cerebral computed tomography scans and endocrinological studies

Cranial irradiation in children with acute lymphatic leukaemia (ALL) decreases the risk of CNS relapse but is associated with serious long-term side-effects. We present the long-term outcome of 21 children with high-risk ALL who received prolonged intrathecal chemotherapy instead of the recommended cranial irradiation. Intrathecal triple therapy (methotrexate, hydrocortisone, and cytarabine) was administered every 2nd month throughout the maintenance phase. The average number of courses of intrathecal methotrexate was 8.7 and of triple 9.0. The 5-year event-free survival was 79%. No CNS relapses occurred. CT scan was performed at diagnosis, at cessation of therapy, and 3 years thereafter. No density abnormalities, pathological contrast enhancement, ventricular dilatation, or calcifications were found. One child showed cortical atrophy both at diagnosis and at cessation of therapy. There was a slight decrease in height SDS with time but no change in weight SDS. Delayed bone age was found in 5 children. No abnormalities of growth hormone, thyroid, adrenal, or gonadal function were observed.

CONCLUSION

The study indicates that extended intrathecal chemotherapy in children with high-risk ALL may provide an effective protection from CNS relapses and is associated with a low risk of long-term side-effects.

Clinical and laboratory evaluation of 40 patients with Sheehan's syndrome

Forty patients with typical obstetric history of Sheehan's syndrome were reviewed retrospectively. Together with baseline laboratory values, insulin hypoglycemia test was evaluated in 15 patients, thyrotropin-releasing hormone (TRH) in 27 and luteinizing hormone-releasing hormone (LH-RH) in 7 patients. Baseline hormone values suggested secondary hypothyroidism, hypogonadotropic hypogonadism and hypocortisolemia. According to the results of the anterior pituitary stimulation tests, one patient (6.6%) showed normal cortisol response and one patient (6.6%) showed normal growth hormone response to hypoglycemia. Nine patients (33.3%) who were clinically and biochemically hypothyroid demonstrated adequate TSH response to TRH. None of the patients showed normal prolactin response to TRH. Four out of seven amenorrheic patients (57.1%) had adequate follicle-stimulating hormone and/or LH responses to LH-RH. It has been concluded that isolated anterior pituitary hormone deficiencies may occur in patients with Sheehan's syndrome. Prolactin response to TRH seems the most sensitive screening test for detecting Sheehan's syndrome in patients with typical obstetric history.

Plasma concentrations of FSH, LH, thyroid-stimulating hormone and growth hormone after exogenous stimulation with GnRH, TRH and GHRH in Booroola ewes that are homozygous carriers or non-carriers of the FecB gene

The aim of the present study in Booroola ewes, either homozygous (BB) or non-carriers (++) of the FecB gene, was to test the specificity of the pituitary responses to exogenous hypothalamic releasing hormones by examining the plasma concentrations of FSH, LH, thyroid-stimulating hormone (TSH) and growth hormone (GH) after injecting the animals with different doses of GnRH, thyroid-releasing hormone (TRH) or growth-hormone-releasing hormone, (GHRH) which were administered on separate occasions. The animals (n = 8 per dose) received 0, 3.1 or 12.5 micrograms of thyroid-releasing hormone and GnRH (i.v.), whereas they (n = 9-13 per dose) received 0, 6.0 or 16.0 micrograms GHRH (i.v.). For each experiment there were no differences between the genotypes in bodymass or age. Gene-specific differences in the mean pretreatment concentrations of plasma FSH (BB > ++; P < 0.05) but not of LH, TSH or GH were noted. After treatment with GnRH, TRH or GHRH, significant effects of dose were noted for all the hormones; however, a gene-specific effect was observed only for FSH in response to GnRH (BB > ++; P < 0.01) with no genotype x dose interaction (ANOVA). For LH, the effects of genotype and the genotype x dose interaction almost reached significance at the 5% level (genotype, P = 0.055; genotype x dose, P = 0.067). For TSH and GH the respective genotype x dose interactions were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

A prospective study of hypothalamus pituitary function after cranial irradiation with or without radiosensitizing chemotherapy

Hypopituitarism can occur after cranial irradiation. Combined chemotherapy (CT) and radiotherapy (RT) have greatly improved the survival of patients with nasopharyngeal carcinoma (NPC). We studied 37 NPC patients who received RT and/or CT prospectively to determine if combined CT worsens the radiation damage. Patients were studied before, 6 months, 1 year and 2 years after treatment, with 4 combined hypothalamic releasing hormones stimulation test and insulin hypoglycemic test. Five developed hypothyroidism and 3 developed hyperprolactinemia after treatment. The TSH response to TRH progressively increased. In male patients who received RT only, the LH response to GnRH was reduced after RT. The FSH response to GnRH increased 6 months and 1 year after RT, and returned to pretreatment level 2 years after RT. In male patients who received RT and CT, after an initial rise 6 months after treatment, both FSH and LH responses to GnRH declined. The ACTH response to ovine CRH was decreased 6 months after RT and remained so later on, while the cortisol response became prolonged and enhanced progressively after RT. The peak GH response to GRH increased significantly 1 year after RT in patients who also received CT. The GH response to insulin hypoglycemia was also increased after RT while the cortisol response remained the same. In conclusion, cranial irradiation caused a progressive impairment of the hypothalamus-pituitary-endocrine axes. Combined CT may mask the radiation damage to GnRH neuron by inducing primary hypogonadism. There may be hippocampal damage in addition to hypothalamo-pituitary damage after cranial irradiation.

Fetal hypopituitarism: perinatal endocrine and morphological studies in two cases

We report two infants with congenital absence of the anterior pituitary gland, documented by magnetic resonance imaging (MRI) or autopsy. In cord plasma obtained at birth from both infants, prolactin (PRL), pituitary growth hormone (hGH), placental growth hormone (hPGH) and thyrotropin (TSH) were undetectable; cortisol was low; thyroxine (T4) was 31 nmol/l in one infant and 85 nmol/l in the other infant who had been treated prenatally with intra-amniotic L-T4 administration. In maternal plasma at birth, PRL, hPGH and T4 were normal and hGH was undetectable. These observations suggest that plasma hGH and PRL in the fetus are exclusively of fetal pituitary origin, hPGH is secreted into the maternal circulation and is not transferred to the fetus and fetal growth can be normal in the absence of hGH, hPGH and PRL in fetal plasma.

The anterior pituitary lobe in patients with cystic craniopharyngiomas: three cases of associated lymphocytic hypophysitis

Specimens of the anterior pituitary lobe were investigated histologically in 28 craniopharyngioma patients operated on trans-sphenoidally. The pituitary glands in 3 patients revealed lymphocytic invasion giving a histological appearance typical of lymphocytic hypophysitis (incidence: 11%). At follow-up examination all three patients with associated lymphocytic hypophysitis had complete pituitary insufficiency, whereas only 36% of the craniopharyngioma patients without associated lymphocytic hypophysitis were in this poor postoperative endocrine state. The phenomenon of associated lymphocytic hypophysitis in craniopharyngioma patients has not been reported so far. This might be due to the fact that investigators have failed to systematically examine the anterior pituitary lobe in craniopharyngioma patients. The 60 cases of lymphocytic hypophysitis reported in the literature occurred, for the most part, in women during late pregnancy or shortly after delivery. An auto-immune origin is assumed in this type of inflammation. In contrast to this pathophysiological mechanism, we assume a local induction of inflammation resulting from the craniopharyngioma cyst in our 3 patients.

The effects of sumatriptan on pituitary secretion in man

Sumatriptan, a new antimigraine drug with high affinity and selectivity for certain 5-hydroxytryptamine (5-HT1D) receptor subtypes, was administered to 12 normal subjects, in order to investigate the effects of 5-HT receptor activation on anterior pituitary secretion. Sumatriptan increased plasma growth hormone (GH) levels from 2.5 +/- 0.5 mIU/l in basal conditions to 17.3 +/- 2.6 mIU/l 30 min after administration of the drug. After pre-treatment with cyproheptadine, an anti-serotoninergic drug known to inhibit GH secretion, the mean integrated sumatriptan-induced GH response decreased from 14.8 +/- 3.9 muI/l*hr to 3.7 +/- 1.7 mIU/l*hr. Sumatriptan administration did not have any effect on the secretion of the other anterior pituitary hormones. It is concluded that sumatriptan selectively increases GH secretion in man, but the exact nature of the receptors involved is not yet known.

Prolactin, growth hormone and insulin-like growth factor-I in newborn children of smoking mothers

OBJECTIVE

Since maternal smoking causes fetal circulatory abnormalities, as well as disturbances of the maternal endocrine equilibrium, we measured the PRL, hGH and insulin-like growth factor-I (IGF-I) concentrations in the cord and venous blood of neonates of smoking mothers to determine whether or not the tobacco smoke affects the endocrine status of the neonate.

DESIGN

The above hormones were measured in the cord blood of the newborns of both smoking and non-smoking mothers. Also, PRL and hGH were determined at 24 and 72 hours after birth in newborns of both groups.

PATIENTS

Fifty-three newborns of smoking and 47 newborns of non-smoking mothers were investigated. Seventeen of the newborns of the smoking and 21 of the non-smoking mothers were preterm. The remainder were full-term.

MEASUREMENTS

PRL was measured with a solid-phase immunoradiometric assay, hGH with a solid-phase two-site immunoradiometric assay and IGF-I with a solid-phase radioimmunoassay after extraction with acid-ethanol.

RESULTS

The median value of PRL in the 17 preterm newborns of smoking mothers was 4941 mU/I (range 1322-7230), whereas in the 21 preterm newborns of non-smoking mothers it was 2013 mU/I (range 243-4740) (P = 0.0002). The median hGH value in the above subjects was 102.0 mU/I (range 35.2-208.4) and 59.8 mU/I (range 11.6-134.2), respectively (P = 0.0039). The median IGF-I was 580.7 U/I (range 253.2-4851.1) and 530.6 U/I (range 239.6-3591.5), respectively (P = 0.429). In the 36 full-term newborns of smoking mothers the median PRL value was 5171 mU/I (range 2074-7530), whereas in the 26 full-term newborns of non-smoking mothers it was 5081 (range 244-6540) (P = 0.048). The median hGH was 69.6 mU/I (range 42.3-280.0) and 32.2 mU/I (range 6.2-200.0), respectively (P = 0.0031). Also, the median IGF-I value was 926.3 U/I (range 348.5-5344.7) and 462.1 U/I (range 250.2-1578.7), respectively (P = 0.0024). On the 3rd day the PRL in the preterm neonates of both smoking and non-smoking mothers showed the same 16.5% drop, and thus the difference between the groups was maintained. A similar reduction in the hormone levels was observed in the full term neonates.

CONCLUSIONS

The findings indicate that the maternal tobacco-smoking causes disturbances of the endocrine status of the fetus, as shown by the increased levels of PRL, hGH and IGF-I, which are more pronounced between 30 and 37 weeks of gestation than at term.

The effects on basal anterior pituitary hormone concentrations by cranial irradiation in patients with nasopharyngeal carcinoma

Hypopituitarism occurring in patients who received external cranial radiation therapy (RT) have been increasingly recognized. Fourteen healthy patients were collected as control Group I, and 25 patients with nasopharyngeal carcinoma (NPC) were enrolled as Group II. Another 18 NPC patients were enrolled as Group III. Blood was sampled from Group I, Group IIB (before RT), Group IIA (one week after RT) and Group IIIA (1 to 1.5 years after RT). The basal samples were taken for growth hormone (GH), adrenocorticotropic hormone (ACTH), cortisol, follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), thyrotropin (TSH), triiodothyronine (T3) and thyroxine (T4). The results showed the T3 level was statistically low in Group IIB compared with Group I. The serum GH and FSH (male only) levels were higher and with statistical significance in Group IIA compared Group IIB. Both GH and ACTH levels decreased and PRL increased with statistical significance in Group IIIA compared with Group IIA. The ACTH decreased with statistical significance in Group IIIA compared with Group IIB. Clinical damage to the pituitary is usually manifested months to years after RT. Therefore, a careful exclusion of these glands from radiation treatment fields is recommended whenever possible.

Acute effects of cocaine on anterior pituitary hormones in male and female rhesus monkeys

The effects of acute cocaine administration (0.4 or 0.8 mg/kg) on anterior pituitary hormones were studied in four male and six female adult rhesus monkeys during the midluteal phase of the menstrual cycle (days 20-23). Progesterone levels averaged 15.7 +/- 3 and 10.6 +/- 2.8 ng/ml before low and high dose cocaine administration. Integrated plasma samples were collected every 10 min for 40 min before i.v. administration of cocaine, and 11 postcocaine samples were collected over 110 min. Cocaine (0.8 mg/kg) stimulated a significant increase in luteinizing hormone (LH) within 10 to 20 min (P < .01) and LH reached peak levels (59-60% above base line) within 30 min after cocaine administration in both males and females. Plasma cocaine levels averaged 289 +/- 23 and 346 +/- 73 ng/ml at 10 min after i.v. cocaine (0.8 mg/kg) administration in males and females, respectively. Follicle stimulating hormone levels were unchanged in midluteal females. Male testosterone increased by 50% above average base-line levels 50 min after the LH peak (80 min postcocaine). These data are consistent with our previous findings that cocaine increased LH and enhanced luteinizing hormone-releasing hormone-stimulated LH in early follicular females. The low dose of cocaine did not change basal levels of LH and follicle stimulating hormone in midluteal females and both LH and testosterone were unaffected in males. Cocaine plasma levels averaged 97.6 +/- 29 and 68.3 +/- 9.1 ng/ml at 10 min after 0.4 mg/kg of cocaine in males and females, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypopituitarism after tuberculous meningitis in childhood

OBJECTIVE

To study the prevalence and pathogenesis of hypopituitarism following tuberculous meningitis in childhood.

DESIGN

A retrospective cross-sectional study.

SETTING

A university teaching hospital and a tuberculosis referral center.

PATIENTS

Forty-nine patients, aged 23.4 +/- 6.0 years (mean +/- SD), who had tuberculous meningitis in childhood (age at diagnosis, 5.9 +/- 5.0 years) were studied.

MEASUREMENTS

A detailed assessment of hypothalamic-pituitary function, including conventional stimulation tests and responses to four hypothalamic releasing hormones, was done. Magnetic resonance imaging of the hypothalamic-pituitary region was performed in patients with abnormal endocrine function.

RESULTS

Ten patients were found to have abnormal pituitary function: Seven had growth hormone deficiency, four of whom also had gonadotropin deficiency; the other three had gonadotropin deficiency, corticotropin deficiency, and mild hyperprolactinemia, respectively; none had diabetes insipidus. Among those with growth hormone deficiency, a significant correlation (r = 0.749, P < 0.05) was found between the height standard deviation score and the age at diagnosis of tuberculous meningitis. Growth hormone, corticotropin, and gonadotropin responses to growth hormone releasing hormone, corticotropin releasing hormone, and gonadotropin releasing hormone, respectively, suggested a hypothalamic defect in five patients. Magnetic resonance imaging scans of the hypothalamic-pituitary region were abnormal in five patients.

CONCLUSIONS

Hypopituitarism was documented in 20% of a small subset of patients years after recovery from tuberculous meningitis in childhood. The cause appears to be tuberculous lesions affecting the hypothalamus, pituitary stalk and, directly or indirectly, the pituitary itself. Early recognition and treatment can be beneficial.

Adenohypophyseal and sex hormones in pediatric rheumatic diseases

Studies in adults with systemic lupus erythematosus (SLE) have shown normal estrogen and lowered androgen levels in serum and abnormal metabolism of estrogen. In our prospective study we tested the hypothesis that one or more of the following factors account for the increased incidence of SLE and pauciarticular juvenile rheumatoid arthritis (JRA) in females: (a) increased estrogen; (b) decreased androgen and (c) increased estrogen receptor in the peripheral blood mononuclear cells (PBMC). Serum and PBMC were collected from 51 healthy children (36 M: 20 F), 17 with JRA (all female) and 37 with SLE (11 M: 26 F). Estrogen receptor was measured in cytosol from PBMC using monoclonal antibody to estrogen receptor and solid phase enzyme immune assay. Serum levels of estrogen, androgen, prolactin, follicle stimulating hormone (FSH) and luteinizing hormone (LH) were measured using standard radioimmunoassay. There were no significant differences in serum levels of estrogen and prolactin between healthy children and patients. Free androgen was lower in postpubertal boys and girls with SLE compared to healthy children. FSH and LH levels were higher in postpubertal boys and girls with SLE compared to healthy individuals. This trend, while not reaching statistical significance, was supported by a higher percentage of female patients with SLE and abnormal serum levels of FSH (p = 0.001), LH (p = 0.004) and prolactin (p = 0.001). The results of these preliminary studies suggest that the role of prolactin, FSH and LH in rheumatic diseases deserves further study.

The function of the hypothalamo-pituitary axis in brain dead patients

In order to find out the function of the hypothalamo-pituitary axis in brain dead patients, pituitary and hypothalamic hormone concentrations were measured and several anterior pituitary releasing tests were carried out in 39 brain dead patients. In addition, cerebral blood flow measurements were simultaneously performed. In almost all cases, the blood concentration of pituitary and hypothalamic hormones were above the sensitivity of the assay. Anterior pituitary releasing tests indicated that efficient functions of the hypothalamus were severely suppressed, while the normal secretory mechanism of the anterior pituitary was partially preserved in brain dead patients. Histological changes of hypothalamic neurons varied from barely detectable ghost cells to nearly normal cells even in the same case. Although, the remaining circulation seemed not to be sufficient enough to maintain integrated hypothalamo-pituitary function, as shown by the examinations of cerebral blood flow, the presence of hypothalamic hormones in the systemic circulation suggests that these hormones were released and carried from the hypothalamus by minimal flow which is preserved even after the diagnosis of brain death.

[Probable role of obesity on the adrenal response to acute stimulation with adrenocorticotrophic hormone in eumenorrheic and hirsute, non-eumenorrheic women]

Obesity, the most frequent nutritional problem throughout the rich nations, can have a vast and significant influence on different aspects of endocrinology, in particular on ovulation disfunction, on hyperandrogenemia, on hormone-sensitive carcinomas. Our study proposes to value the response to adrenal cortex to stimulation with adrenocorticotropin (ACTH) hormone in obese patients, with particular attention to the behavior of adrenocortical androgens and their precursor. We recruited 30 female patients so divided: 12 obese, nonhirsute, eumenorrheic patients (group A); 10 normal weight, hirsute patients in situation of secondary amenorrhea (group B); 8 normal weight, nonhirsute, eumenorrheic patients (group C). Cortisol, progesterone, 17 OH progesterone, dehydroepiandrosterone sulfate, androstenedione, testosterone were measured at 60, 120, 180, 240, 300 min during continual infusion i.v., for 5 h, of ACTH 1-17 at 100 mcg dose, in physiological sodium chloride solution. All the women with monthly menstruation were studied between the IV and VIII day of their cycle. In the patients with secondary amenorrhea the value of basic progesterone was used to completely exclude an eventual luteal phase and the relationship LH/FSH was so as to logically exclude a diagnosis of polycystic ovary. This exclusion was also confirmed from the report of the ultrasonography. The basic concentration of hormone dosage is not significantly different between the patients of the three groups, except for T. This hormone is different because it is found to be significantly (p < 0.01) increase in the hirsute patients, in respect of the patients in group A and group C. Also P and 17OHP have been found to be higher, if only in insignificant measure, in hirsute patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Hormone changes in men with spinal cord injuries

The steady state profiles of 63 men with traumatic spinal cord injuries (24 quadriplegics and 39 paraplegics; average age of 31.2 +/- 6.8 yr; 18-44 yr) were studied. The average length of post-traumatic period was 6.2 +/- 5.0 yr, ranging from 8 months to 20 yr. It was found that all the subjects had normal serum thyroxine, thyrotropin, cortisol, growth hormone and plasma adrenocorticotropic hormone. Seven cases (11.1%) had low serum triiodothyronine and eight cases (12.7%) had low serum testosterone. On the other hand, 17 cases (27.0%) had hyperprolactinemia; 9 cases (14.3%) had elevated serum testosterone level; 6 cases (9.5%) had elevated serum follicle-stimulating hormone; and 4 cases (6.3%) had elevated serum luteinizing hormone. The level of spinal cord injury, injury period and patient age had no correlation with other serum hormone changes except that quadriplegic subjects had lower serum triiodothyronine than the paraplegic, with a mean of 1.42 +/- 0.30 v 1.70 +/- 0.36 nmol/liter (P < 0.005). Of the eight subjects who had low serum testosterone, none had elevated gonadotropin. There were also eight subjects with elevated follicle-stimulating hormone and/or luteinizing hormone, six of them had normal serum testosterone and two had elevated serum testosterone. This suggested their hypogonadism did not result primarily from classic primary gonadal failure. It could be speculated that other testicular paracrine factors and/or alteration of hypothalamus-pituitary-testicular axis are involved in the pathogenesis of hypogonadism. Further studies in this field will provide information regarding male reproductive physiology and may have impact on fertility enhancement options for men with spinal cord injuries.

Rhythmic and nonrhythmic modes of anterior pituitary gland secretion

Because of confounding effects of subject-specific and hormone-specific metabolic clearance, the nature of anterior pituitary secretory events in vivo is difficult to ascertain. We review an approach to this problem, in which deconvolution analysis is used to dissect the underlying secretory behavior of an endocrine gland quantitatively from available serial plasma hormone concentration measurements assuming one- or two-compartment elimination kinetics. This analytical tool allows one to ask the following physiological questions: (a) does the anterior pituitary gland secrete exclusively in randomly dispersed bursts, and/or does a tonic (constitutive) mode of interburst hormone secretion exist? and (b) what secretory mechanisms generate the circadian or nyctohemeral rhythms in blood concentrations of pituitary hormones?(ABSTRACT TRUNCATED AT 250 WORDS)

[Macroprolactinoma at 6 years of age: diagnostic difficulties]

Prolactinoma is rare in childhood and adolescence. The earliest known diagnosis was reported in a patient at 8 years of age. We report the case of a sellar tumor found in a 6 years old girl. After a long symptomatic period she was brought for treatment. At this time she had partial papillar atrophy, hyperprolactinemia, and diminished reserve of growth hormone and cortisol. Due to rapid visual deterioration, she was submitted to a frontotemporal craniotomy for suspected craniopharyngioma. The tumor tissue immunohistochemistry was positive for prolactin. It is concluded that prolactinoma must be considered in differential diagnosis of sellar tumors in childhood since it benefits from a less aggressive therapy.