Assessment of hormone loss through hemofiltration.

The concentrations of testosterone, cortisone, gastrin, insulin, gastric inhibitory polypeptide (GIP), somatomedin B, parathyroid hormone (PTH), human growth hormone (HGH) and thyroid stimulating hormone (TSH) have been determined in the plasma and the ultrafiltrate of five uremic patients undergoing intermittent hemofiltration treatment. There was a considerable loss of gastrin, insulin, GIP, somatomedin B and PTH by hemofiltration treatment. The plasma concentrations, however, did not decrease except for immunoreactive-PTH (IR-PTH) which returned from elevated to normal levels. Cortisone, HGH and TSH concentrations in the ultrafiltrate were below the measureable range. A significant elimination of 11-hydroxylated androstans by hemofiltration may have a positive effect on the disturbed steroid metabolism. Results indicate that hemofiltration does not cause a hormone deficiency syndrome. On the contrary, the loss of degradation products of hormones with disturbing biological activity may be a favorable effect of the hemofiltration treatment.

Metabolic and clinical studies on patients with acromegaly treated with bromocriptine over 22 months.

In twenty-two patients with active acromegaly who were untreated or unsuccessfully operated or irradiated (mean growth hormone (GH) values greater than 4 ng/ml) the following investigations were performed: routine laboratory tests, tomography of pituitary fossa, oral glucose tolerance tests, TRH and other pituitary function tests and GH profiles over 5-10 h before and during bromocriptine treatment with daily doses between 7.5 and 50 mg. In seventeen patients GH was suppressed to less than 50% by bromocriptine, in thirteen of them it was normalized on at least one occasion. A TRH induced GH release was observed in all but two responders to bromocriptine before therapy. This effect of TRH was not blunted during treatment with bromocriptine and also in the two patients with negative tests before therapy a significant GH increase was observed. In no non-responder to bromocriptine was a significant increase of GH after TRH observed. One patient showed a secondary resistance to bromocriptine during a period of treatment with griseofulvin. In the remaining sixteen patients the GH suppression has been consistent for between 3 and 22 months. A single dose of pimozide abolished the bromocriptine effect on GH totally in one patient; in others a slight or no significant effect was observed. Tissue swelling and sweating decreased in all bromocriptine responders and glucose tolerance improved in five patients. In four diabetic patients a partial or full remission of diabetes occurred. Apart from postural hypotension after the first administration in two patients no other severe side effects have been observed. Sella size and the other pituitary functions did not change during the time of the study. It seems that a high percentage of acromegalics may be successfully treated with bromocriptine.

Elimination of hormones through hemofiltration.

The concentrations of testosterone, cortisone, gastrin, GIP, somatomedin B, insulin, HGH, and TSH have been determined in the plasma and the ultrafiltrate of five uremic patients undergoing intermittent hemofiltration treatment. There was a considerable loss of gastrin, GIP, somatomedin B, and insulin by hemofiltration treatment; the plasma concentrations, however, did not decrease. Cortisone, HGH, and TSH were not detectable in the ultrafiltrate. Our results therefore indicate that hemofiltration does not cause a hormone deficiency syndrome. On the contrary, the loss of degradation products of hormones with disturbing biological activity may be a favourable effect of the hemofiltration treatment.

Effect of the dopamine receptor blocking agent pimozide on the growth hormone response to arginine and exercise and on the spontaneous growth hormone fluctuations.

Pimozide, a specific blocker of dopamine receptors, was administered orally to 10 diabetics for 2 days before an arginine-hydrochloride infusion. In 8 healthy volunteers and 20 diabetics exercise tests on a bicycle ergometer were performed with a load of 100 Watts and 50 Watts respectively without or after a single dose of pimozide 30 min before the test. In 4 male diabetics day profiles of growth hormone (GH) were estimated without and during treatment with pimozide for 4 days. The arginine and exercise induced GH release was found to be significantly lowered by pimozide, whereas the marked spontaneous fluctuations in the diabetics were even enhanced by pimozide. These data support the concept of the involvement of dopaminergic stimulation in the response of GH to arginine and exercise. The spontaneous fluctuations of GH, however, seem to be regulated by other neuroendocrine mechanisms.

Effects of dexamethasone on thyrotrophin and prolactin plasma levels in rats.

In the present study the influence of dexamethasone treatment of rats on the basal values of thyrotrophin (TSH) and prolactin (PRL) and the response of both hormones to thyrotrophin releasing hormone (TRH) has been investigated. Male rats were given 100 mug of dexamethasone/rat for 8 days at the same time of day. Four hours after the last administration of dexamethasone 200 ng or 100 mug of TRH/rat was injected ip. Blood was collected 10 min later by decapitation. TSH and PRL were estimated by radioimmunoassay (RIA) using the NIAMD kits. The basal and TRH stimulated values of PRL in plasma were significantly lower in dexamethasone treated rats than in controls (P less than 0.01). The basal TSH levels in the treated animals were also lowered (P less than 0.05). After 200 ng TRH/rat the increase in TSH was not as high in both groups than after the administration of 100 mug/rat. There was no significant difference between the response of TSH to TRH in the dexamethasone treated and the control rats. The different effects of dexamethasone on PRL and TSH release after TRH may give a further insight into the different regulating mechanisms of both hormones in rats.

Plasma prolactin levels after TRH and chlorpromazine in normal subjects and patients with impaired pituitary function.

Basal plasma prolactin levels and values after stimulation with TRH and chlorpromazine respectively were measured. TRH tests were performed in 50 healthy subjects (25 women and 25 men). The basal prolactin levels and the maximum increment were found to be as follows in women 22.02 ng/ml

[Therapy of acromegaly using bromocriptine]. / Die Behandlung der Akromegalie mit Brompcriptin

Oral administration of 1.0 or 2.5 mg bromocriptine (CB 154: 2-brom-alpha-ergocryptine) in nine of twelve patients with active acromegaly resulted in a reduction of growth hormone level by 80-90% over 8-10 hours. During treatment for 2-9 months with daily doses of 4.0 to 10.0 mg bromocriptine, there was a sustained reduction of growth hormone levels in these patients. At the same time soft-tissue swellings and tendency towards sweating decreased. In two patients with diabetes mellitus the blood sugar profile improved and in one of them the insulin dose could be markedly reduced. The rise in growth hormone levels after TRH administration also occurred during bromocriptine treatment. In those patients in whom growth hormone levels failed to react to either acute or chronic administration of bromocriptine no rise followed TRH administration. It is possible that in these patients there is a hypophyseal adenoma without hypothalamic control. On gradually increasing dosage bromocriptine was tolerated without side effects.