摘要:

SUMMARYIn order to define nyctohemeral plasma ACTH secretory patterns, frequent plasma ACTH samples were obtained in seven patients with untreated Cushing's disease (i.e. pituitary‐dependent Cushing's syndrome), five Cushing's patients treated by bilateral adrenalectomy, four of whom had Nelson's syndrome, and one patient with 21‐hydroxylase deficiency (congenital adrenal hyperplasia). A nyctohemeral rhythm of plasma ACTH concentration was apparent in the one patient with the adrenogenital syndrome but not in those with Nelson's syndrome or Cushing's disease.The effect of graded doses of dexamethasone, 2, 8 or 32 mg per 24 h period, on plasma ACTH concentrations was studied in patients with untreated or treated Cushing's disease or Nelson's syndrome. In all of these hypercorticotrophic states, the mean plasma ACTH concentration was not significantly affected by the smallest dose of dexamethasone, was partially suppressed by the intermediate dose, and further suppressed by the largest dose. In contrast, the patient with congenital adrenal hyperplasia and elevated plasma ACTH concentrations showed complete suppression of plasma ACTH levels following the smallest dose of dexamethasone. These findings indicate that there is resistance to ACTH suppression by dexamethasone in all stages of Cushing's disease and suggest that negative feedback of glucocorticoids may be involved in the pathogenesis of this dise

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1976.tb01959.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

SUMMARYHypothalamic‐pituitary function was examined in seventeen patients treated in the past for extrasellar intracranial tumours. All patients had received a course of external cranial irradiation. Biochemical abnormalities of endocrine function were present in almost all of the patients. In particular, the growth hormone response to insulin induced hypoglycaemic stress was impaired in eleven out of fifteen patients. Preliminary data from a group of seven patients with intracranial tumours prior to radiotherapy are also presented. The possibility that cranial irradiation causes hypothalamic‐pituitary dysfunction is discussed. The results suggest that endocrine assessment should be considered in patients who have been treated for intracranial tumours, even in the absence of direct pituitary involvem

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1976.tb01960.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

SUMMARYThe inactivation of synthetic [3H]thyrotrophin‐releasing hormone (TRH) by plasma was studied in rats treated with propylthiouracil (PTU) alone or with PTU and thyroxine. 48 h after the onset of treatment with thyroxine, the capacity of rat plasma to inactivate [3H]TRH was significantly increased. The percentage of deamidation of TRH to TRH‐free acid was increased 2‐fold after 4 days of administration of thyroid hormone. The inactivation of TRH by plasma from hypothyroid patients was compared to that obtained from hyperthyroid patients. Extraction of human plasma incubated with [3H]TRH, followed by thin‐layer electrophoresis, showed that transformation of [3H]TRH into TRH‐free acid was 44% higher in plasma from hyperthyroid than from hypothyroid patients (P<0.05). These data suggest that the inactivation process of TRH by blood proteins could be an important factor in the regulation of the hypothalamo‐hypophyseal‐thyroid axis i

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1976.tb01961.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

SUMMARYTSH and prolactin secretory patterns in thyroid disease have generally been reported as concordant. We studied TSH and prolactin responses to TRH infusion (500 μg) in euthyroid individuals previously treated for thyrotoxicosis with131I or antithyroid drugs. The131I‐treated group (seven men, twenty women) had been clinically and biochemically euthyroid (normal serum thyroxine and triiodothyronine levels) for 6 months to 4.5 years (χ= 17.1±4.1 months). Based on maximal TSH increment (ΔTSH), three patient groups were identified: Group 1 [normal ΔTSH, n = 6]: Δ prolactin was normal in two, blunted in one and exaggerated in three. Group 2 (exaggerated TSH response, n = 8): Δ prolactin was normal in two, blunted in one and exaggerated in five. Group 3 (TSH nonresponders, n = 13): Δ prolactin was normal in five, blunted in three, and exaggerated in five.Eleven patients (three men, eight women) were studied after 6 months antithyroid‐drug treatment. All were clinically and biochemically euthyroid. All but one showed a blunted TRH‐TSH response. All three men showed an exaggerated Δ prolactin as did four of eight women. Three women showed a blunted Δ prolactin and in one, Δ prolactin was normal.Thus, TRH‐induced TSH and prolactin response patterns in treated thyrotoxicosis are not uniformly concordant, and, while a blunted or absent TSH response commonly persists long after euthyroidism has been restored, this is most frequently accompanied by a normal or exaggerated

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1976.tb01962.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

SUMMARYThe cortisol binding capacity of maternal and cord plasma samples obtained at delivery from fifteen women and their normal infants and from seven women and their anencephalic infants was measured at 4°C by a gel filtration technique. The concentration of oestrogen in these samples was measured by radioimmunoassay.There was no significant difference (ttest) between the cortisol binding capacity of peripheral plasma from women with normal infants (1.5±0.24 μmol/l, mean ± SD) and from those who delivered anencephalic infants (1.35 ± 0.30μmol/l), nor between the cortisol binding capacity of cord plasma from anencephalic infants (0.47 ± 0.04 μmol/l) and that of normal infants (0.37 ± 0.10 μmol/l). However, mean oestrogen concentrations in maternal and cord plasma from the pregnancies with an anencephalic fetus were significantly lower (P<0.01) than in the corresponding samples from normal pregnancy.It is concluded that oestrogen concentrations in maternal and cord plasma in normal pregnancy at delivery are much greater than those required to account for the increase in plasma cortisol binding capacity. Since plasma cortisol binding capacity in pregnancy with an anencephalic fetus is not diminished, the reduced excretion of corticosteroids relative to normal pregnancy in this condition is unlikely to be due to alterations in cortisol metabolism associated with a lower plasma cortisol binding

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1976.tb01963.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

SUMMARYIn order to provide a comprehensive account of pituitary‐testicular function in man, 466 subjects, ranging in age from 2 to 101 years, were studied to examine blood levels of the pituitary gonadotrophins (LH and FSH), the sex steroids testosterone and oestradiol, the binding capacity of the sex hormone binding globulin (SHBG), the free testosterone and oestradiol fractions, and the transfer constant for the peripheral conversion of testosterone to oestradiol. The results were compared with clinical indices of testicular size, sexual function and secondary sex hair distribution. Serum LH and FSH were low before puberty, increased in pubertal adolescents to levels somewhat above those of adults and subsequently increased progressively over the age of 40 years. Testosterone levels fell slowly after the age of 40, while there was a slight rise in plasma oestradiol with increasing age. FSH and testosterone showed small seasonal variations in young adult men, the lowest values being seen in winter. SHBG binding capacity was high in two prepubertal boys, fell in adult men, but increased in old age. Free testosterone and oestradiol levels fell in old age. The metabolic clearance rates (MCR) of testosterone and oestradiol also fell in old age, while the conversion of testosterone to oestradiol was increased. Many correlations were observed between various hormonal and clinical measurements. The evidence is consistent with a primary decrease in testicular function over the age of 40 year

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1976.tb01964.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

SUMMARYThree cases of panhypopituitarism and five of isolated growth hormone dificiency which occurred following previous external irradiation of tumours distant from the adenohypphysis are described. The hypothalamic pituitary region received between 2800 and 12000 rads in each case, 1‐9 years before endocrine deficiency was recognized. Evidence is presented that th esite of damage is in the region of the hypothalamus rather than the pituitary gland itself.Individuals treated with X‐ray therapy in whom the hypothalamic‐pituitary region is exposed to irradiation would appear to be at risk of developing some degree of delayed hypothalamic‐pituitary dysfunction.Early reports of the effects of external radiotherapy on hypothalamo‐hypophyseal function suggested that the pituitary gland was resistant to damage from irradiation, but that the hypothalamus and adjacent neural tissues were more sensitive (Kellyet al., 1951; Arnold, 1954). Radiotherapy to malignant tumours distant from the pituitary has not been thought to result in endocrine dysfunction even when the hypothalamo‐hypophyseal region was included in the field of irradiation (de Schryveret al., 1973). Only three reports of documented hypopituitarism following external radiotherapy in such circumstances have been recorded (Tan&Kunaratnam, 1966; Larkins&Martin, 1973;et al., 1975).This paper details the endocrine status of eight patients treated by radiotherapy for malignant disease distant from the pituitary, in whom the hypothalamus was also irradiated. Two of these patients have been reported previously (Larkins&Martin, 1973) and all were found to have severe or partial hypo

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1976.tb01965.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

SUMMARYAn evaluation of twenty‐one boys, including a discordant pair of identical twins, is presented in whom bilateral anorchia was found with a negative family history and without history of breech presentation or of postnatal testicular trauma, torsion or orchitis. The most likely cause is prenatal testicular torsion. The incidence of the condition in our hospital is 1 in 177 cases of cryptorchidism. Prepubertal growth was normal beofore treatment, and testosterone replacement therapy allowed a normal pjubertal growth spurt and skeletal maturation. Although demonstrable basal urinary tstosterone was found in the subjects with a postpubertal bone age, most patients tested showed no increase after stimulation with human chorionic gonadotrophin. In the presence of a normal penis and scrotum, such findings, together with a high basal FSH and an increased response of plasma LH to LHRH, make surgical exploration unnecessary. In the rare patient who shows a positive but subnormal response of testosterone to HCG, Leydig cells are presumed to be present either ectopically or in rudimentary testes, and further surgical exploration is indicated.Anorchia, or absence of the testes, may be congenital or acquired postnatally through trauma or testicular torsion. Several conditions may mimic congenital anorchia, the most common being virilization of a female fetus as a result of congenital adrenal hyperplasia, meternal androgen ingestion, or by maternal androgen secreting tumours.Congenital anorchia has been said to occur in 1 in 20 000 male subjects (Bobrow&Gough, 1970) but despite this estimated prevalence there have been only eighty or so cases reported in the literature during the last 100 years. We have investigated twenty‐one additional cases, and wish now to report our observations. The reasons for the study are, first, that the number of cases, the largest series reported, allowsa thorough clinical and therapeutic evaluation; second, to report results on the testosterone response to human chorionic gonadotrophin administration and the luteinizing hormone and follicle stimulating hor

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1976.tb01966.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

SUMMARYIn order to study the role of the oestradiol on the feed‐back mechanism, fourteen men were subjected to LHRH test before and after treatment with oestradiol. The oestrogen was administered i.m., 3 μg/kg/24 h and 150 μg/kg/24 h, in two groups of patients. Doses of 3 and 150 μg respectively produced a reduction of LH release of 74% and 60% below control. FSH response to LHRH was almost abolished by oestrogens. Our findings show that oestrogensin men decrease the pituitary response to

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1976.tb01967.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY

摘要:

SUMMARYNot all the varied clinical disorders in which aldosterone and the mineralocorticoid hormones are involved have been reviewed. Only those disorders in which the mineralocorticoid hormones and their regulatory factors are the principal cause of the biochemical and clinical abnormalities have been examied. These are many and varied. Appreciation of the extent and magnitude of their involvement in the regulation of blood pressure, body fluids, and electrolyte composition continues to grow.The major direct clinical impact of the mineralocorticoid hormones appears to be in two areas: hypertension and potassium homeostasis. Their part in the mosaic of hypertension is established in primary hyperaldosteronism, but they also appear to affect and modify the hypertensive process in primary or essential hypertension. The probe continues.Hypoaldosteronism is more than the rare occurrence associated with Addison's disease. It may be the clue to the presence of nonaldosterone mineralocorticoid excess syndromes, and is obviously of critical imporatnce in an increasing number of patients with chronic renal failure of varied aetiologies.

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1976.tb01968.x

出版商:Blackwell Publishing Ltd    

年代:1976

数据来源: WILEY