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To investigate whether a direct influence exists between the prolactin suppressive effect of alpha-bromoergocriptine (CB 154) and the aldosterone response to a potassium stimulation, the present study was performed in 7 anephric patients and in 7 non-nephrectomized patients, all on regular haemodialysis. The increase in the plasma potassium concentration between dialysis was used as a stimulus to the adrenals, and was correlated to the increase in the plasma aldosterone concentration (PAC).Plasma samples were obtained during a control period and during a corresponding period of treatment with bromocriptine. Despite a significant fall in the prolactin levels during the bromocriptine treatment, no differences in the aldosterone response to the increasing potassium concentration in the two periods were found neither in the anephric nor in the non-nephrectomized patients.It is concluded that depression of prolactin levels by the dopamine agonist (bromocriptine) has no influence on the ability of the adrenals to react with an increase in aldosterone secretion following potassium stimulation in dialysis patients with and without preserved renin-angiotensin system.

The secretion and biological activity of thyroid stimulating hormone (TSH) were studied in 22 patients with a pituitary tumour (17 acromegalics and 5 patients with a chromophobe adenoma) and in 36 hypophysectomized patients (16 acromegalics and 20 with a chromophobe adenoma). Thyroid function was assessed by serum thyroxine (T4), serum triiodothyronine (T3), and thyroxine-binding globulin (TBG) concentration. Serum TSH was measured before and after injection of TSH releasing hormone (TRH), and in 19 hypophysectomized patients the T3response after TRH was measured. In addition a TRH test was performed 1–2 weeks after surgery in 11 patients.The basal serum TSH did not differ from euthyroid control values in any of the groups and no late effect of hypophysectomy was observed. Subnormal peak TSH values were seen in 10 out of 37 euthyroid patients, whereas 9 out of 11 hypothyroid patients responded normally. Hypophysectomy caused an immediate but transient decrease in peak TSH in patients with a chromophobe adenoma only. The rise in serum T3after TRH was significantly lower in hypophysectomized patients than in controls. An increase in TSH was followed by a T3response in all patients except in 4 out of 8 euthyroid acromegalics. In patients operated on for a chromophobe adenoma the T3response was correlated with serum T4, whereas this was not the case in acromegalics.

A total number of 103 fullterm (FT), 47 small-for-gestational age (SGA) and 35 preterm (PT) babies were studied from day 1–8 after birth. In FT a surge of TSH was invariably seen, followed by a decrease until normal adult levels were reached on day 2–4 after birth. Serum T4and -T3, concentrations were higher than in adults, significantly correlated and decreased by 30 and 40% respectively from day 2 to 8 after delivery. In SGA the postnatal TSH hypersecretion was more variable. Serum T4and -T3, concentrations were significantly correlated and lower than in FT. Serum T4decreased insignificantly and serum T3seemed to increase during the first week of life. In PT the postnatal TSH increase was highly variably. Serum T4and -T3were lower than in FT and did not change significantly during tne study period; serum T3tended to increase. Birth weight as well as gestational age were correlated with the thyroid hormone concentrations. In babies with gestational age of more than 34–36 weeks normal serum T4and T3concentrations were often observed.It is concluded that the postnatal pituitary-thyroid hyperfunction may be subnormal in SGA and PT babies. If serum TSH concentration is not measured in screening for congenital hypothyroidism these babies may appear as false positives.