Lotte Hummer

No effect of bromocriptine in acromegaly: a controlled trial.

Although bromocriptine, a dopamine receptor agonist, is now widely used in the treatment of acromegaly, there have been no controlled trials of its biochemical or clinical effects on this disorder. We assessed its effects in a double-blind, crossover study. Eighteen patients with acromegaly were given bromocriptine and placebo alternately for three months per medication. Their responses to oral glucose-tolerance tests during the two regimens did not differ significantly. The number of patients noting amelioration of clinical symptoms during treatment with bromocriptine was almost identical to the number with clinical improvement during placebo. We conclude that it remains doubtful whether bromocriptine has a beneficial effect in acromegaly.

The cell types in the adenohypophysis of the South-American lungfish, Lepidosiren paradoxa, with special reference to immunocytochemical identification of the corticotropin-containing cells

SummaryThe histological features and distribution of cell types in the distal lobe of Lepidosiren resemble those of Protopterus. Three “basophilic” cell types are described, whereas the identification of two acidophilic cell types is uncertain. In the intermediate lobe two cell types have been found.Anti-(1–24) ACTH IgG was used in the unlabeled antibody-enzyme method to identify corticotropin-containing cells in the adenohypophysis of Lepidosiren with light and electron microscopy. Corticotropin was demonstrated in cells of the distal lobe and the intermediate lobe. The staining reaction in the distal lobe is localized in the rostrally distributed lead-hematoxylin positive cells. At the ultrastructural level the immunoreaction in these distal lobe cells is localized on polymorphic granules ranging from 130 to 210 nm.Absorption experiments show that the immunoreactive cells in the distal lobe contain at least residues 1–3 and 14–17 of the naturally occurring corticotropin hormone, while the intermediate lobe cells contain α-MSH or at least residues 1–3 of ACTH. The plasma level of corticotropin was determined to be 71 ng/l by means of radioimmunoassay (RIA).

Cerebrospinal fluid ACTH as a marker of central nervous system metastases from small cell carcinoma of the lung

Adrenocorticotrophic hormone (ACTH) concentrations were measured in the plasma and cerebrospinal fluid (CSF) of 107 consecutive patients with known or suspected central nervous system (CNS) metastases secondary to small cell carcinoma of the lung. The combined results of computerized tomography scans, neurologic examination, and autopsy were used to determine the presence or absence of CNS metastases. On the basis of such an assessment, definitive conclusions were possible in 77 patients. CNS metastases were present in 52 cases and absent in 25. The median CSF ACTH level was 30 ng/ml in both groups. None of five patients with very high CSF ACTH concentrations had elevated ACTH concentrations in plasma. Considering the 95th percentile of patients without CNS metastases as the upper limit of normal, 12 patients with metastases and one without had an elevated CSF ACTH value. Eleven patients with leptomeningeal carcinomatosis (MC) did not constitute a special subgroup in this respect. The median ratio of CSF ACTH and plasma ACTH was 1.0 in patients with CNS metastases and 0.4 in those without (P < 0.05). Patients with MC had a median ratio of 1.3, which was significantly different from that of both of the other groups (P < 0.05). Ten patients with CNS metastases (one with MC) and one without exceeded the upper 95th percentile of the CSF/plasma (ACTH) ratio in patients without CNS metastases. The significance levels of these findings disappeared, however, when patients with signs of an elevated ACTH concentration in plasma were excluded. Patients with ectopic ACTH production into CSF do not necessarily have ectopic ACTH production outside the CNS, despite the presence of extracerebral metastases. With the criteria employed in this study, an elevated level of CSF ACTH diagnosed too few patients for the authors to recommend its determination as a single test in diagnosing CNS metastases or MC secondary to small cell carcinoma of the lung.

Comparison of pituitary-adrenocortical response to hypoglycaemia and surgery.

The hypothalamic‐pituitary‐adrenocortical (HPA) responses to the hypoglycaemic stimulus and to operation (laparotomy) are compared. The studies were carried out in eight patients who were subjected to insulin‐induced hypoglycaemia on the day before elective abdominal surgery. Plasma corticotrophin (ACTH) and plasma cortisol concentration increases were virtually identical during the two procedures, which suggests that hypoglycaemia and surgical trauma are comparable stress factors and that the hypoglycaemia test is reliable in predicting the HPA responses to major surgical trauma.

Serum vitamin D metabolites are not related to growth rate, bone mineral content, or serum alkaline phosphatase in male puberty

SummaryTwenty boys were followed during their puberty for about 2 years with examinations every third month. At each examination we determined serum concentrations of 25OHD3, 1,25(OH)2D3, 24,25(OH)2D3, 25.26(OH)2D3,alkaline phosphatase (AP) and testosterone together with bone mineral content (BMC) at the distal forearm. Highly significant increases in both BMC (P<0.001), serum AP (P<0.001), and peak height velocity (PHV) followed the increase in serum testosterone. The boys were grouped according to time of maximal increase in BMC, AP, and PHV. The serum levels of the vitamin D metabolites were related to these points. No significant changes in any of the serum vitamin D metabolites were found. Thus vitamin D metabolism does not seem to be significantly influenced during the period of life when both the linear growth and bone mineralization is maximal.

Human Serum Thyrotrophin Level and Response to Thyrotrophin-Releasing Hormone in the Aged

170 healthy volunteers were investigated, and the clinical and biochemical conditions of selection specified. The fasting morning level of serum thyrotrophin (TSH) was determined in all volunteers and found unchanged within the age interval 18-94 years, independent of sex. This is in disagreement with results obtained by other investigators who found an increase of TSH in old age. The implications of the criteria of selection are discussed. Nycterohemeral rhythm was studied in 16 persons. Rhythmic variation was an inconstant finding, and the pattern in the young could not be distinguished from that in the old. The TSH response to thyrotrophin-releasing hormone (TRH) was determined in 53 persons of various ages and found unrelated to age. Nonetheless, the lowest responses were observed in the aged, but the difference was not statistically significant. Possible physiological interpretations of an unaltered TSH secretion in spite of an age-related decrease in thyroid function are discussed.