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The authors investigated the effect of long-term lithium administration on intracellular calcium mobilization. The subjects were 13 women with bipolar affective disorder stabilized on lithium and 12 matched healthy controls. Total and ionized serum calcium, intracellular calcium ion concentration, plasma parathyroid hormone (PTH) and tyrotropin (TSH), serum electrolytes and cyclic AMP (cAMP) activity in platelets were measured. The serum electrolytes sodium, potassium and creatinine and plasma PTH and TSH were all within normal ranges in patients and controls and no differences were found between the two groups. No difference was found in basal and prostaglandin E1 (PGE1)-stimulated cAMP generation in platelets between patients and controls. However, total serum calcium and ionized serum calcium levels were higher in patients than in controls and there was a significant correlation between these two measures. In the patient group, serum lithium concentration correlated positively with stimulated levels of intracellular calcium in platelets. In the present study, no distinct hyperparathyroidism was found in lithium-treated patients. However, our findings indicate that lithium administration affects calcium metabolism in patients with bipolar affective disorder inducing mild hypercalcemia and a dose-dependent normalized calcium mobilization. Furthermore, our results did not support the hypothesis that lithium's primary site of action in bipolar illness may be on signal transduction mechanisms.

Objective: To analyse the difference in bone mineral content (BMC) between the left and right trunk generally obtained by dual-energy X-ray absorptiometry (DXA) by creating identical images over the liver region and the contralateral side., Patients and Design: Fifty-four patients were selected at random from 1,722 subjects examined by DXA because of osteoporosis. Another five patients were selected who had been followed for osteoporosis by repeated DXA two to five times at intervals from 2 to 36 months. One healthy volunteer was followed for one day by means of DXA total body measurements. All protocols were analysed with respect to BMC, fat mass (FM) and lean tissue mass (LTM) of the imaged trunk and liver., Results: BMC of the right trunk exceeded that of the left trunk in 78% of the investigated subjects. The right (liver) image dominated in all 81 investigations calculated from 60 subjects. There were intraindividual short- and longterm variations between repeated DXA examinations. The amounts of FM and LTM were distributed symmetrically between the right and left trunk., Conclusions: DXA registers BMC in the liver, which explains the general dominance of the right trunk. The absorption over the liver region varies in the same individual in repeated measurements at intervals of hours to months.

The aim of the study was to elucidate if endogenous cortisol, as previously suggested, could be involved in the mechanism behind the reduced serum T3 levels seen in euthyroid patients with various non-thyroidal illnesses. The correlation between the serum levels of T3 and cortisol was investigated in 41 hospitalized patients with non-thyroidal illness during hyperpyrexia. The results showed a correlation coefficient of -0.94, indicating a close reciprocal association between the two hormones. Cortisol may thus be one factor associated with the decreased T3 levels seen in euthyroid patients with non-thyroidal illness. The results also indicate a close parallelism between the total and free T3 levels during hyperpyrexia.

The clinical manifestations in chronic alcoholics may sometimes mimic those of hyperthyroidism. However, diagnostic aids are somewhat contradictory in many cases. Ten chronic alcoholics with symptoms from the sympathoadrenal system were investigated. A significant increase (p less than 0.01) of T3 at 120 min after TRH stimulation was found despite a blunted TSH response (increment less than 3 mU/l) in some cases. This increase in T3 indicates a preserved thyroid function in chronic alcoholics despite generally low basal T3 levels. It is concluded that T3 determinations at 120 min in connection with TRH test may be an essential parameter in evaluating euthyroid function in chronic alcoholics.

A 54-year-old postmenopausal woman is described who quite suddenly experienced intense tenderness and tension in both breasts lasting for about 3 weeks. Subsequently she had a uterine bleeding. Excessively increased levels of estradiol (peak value 2325 pmol/l) were found during the period of mastodynia. Seven months previous to this event, hyperthyroidism had been diagnosed. She had, however, been treated with propylthiouracil and was euthyroid long before and during the period of mastodynia.

The effect of propranolol (40 mg t.d.s.) on the peripheral levels of T4, T3 and reverse-T3 was studied in 26 patients with hyperthyroidism. The compounds were measured by specific radioimmunoassay techniques. The levels were followed for five weeks and compared with the levels before treatment. The results show that propranolol had no significant effect on the peripheral levels of T4 despite a rapid amelioration of clinical symptoms. A significant reduction of T3 levels was obtained during the first to fourth week of treatment. No significant decrease was obtained after the fourth week. A significant elevation in reverse-T3 levels was obtained during the second to fourth week of treatment. No significant change was obtained either during the first week or after the fourth week. Inconsistent fluctuations in hormone levels, both before and during treatment, could be seen in individual cases. The results suggest that the reduction of clinical symptoms must be caused by an extrathyroidal action of propranolol which does not seem to involve the pituitary gland.

The relative discriminatory value of the estimation of the serum reverse-T3 levels for the laboratory diagnosis of hyperthyroidism was investigated in 47 patients with clinical signs or symptoms of hyperthyroidism. The results were compared with those from the determination of the total serum levels of T3 and T4 prior and after correction for the binding proteins. Twenty-three of the patients had normal thyroid function and 24 had hyperthyroidism. The estimation of the total serum T3 level was superior to both the determination of the total serum T4 and reverse-T3 levels even subsequent to correction for the binding proteins.

Ethanol-induced hypoglycemia after 44 hours of complete fasting was allowed to last for four hours. S-T3 decreased significantly (p less than 0.05), by 16.5%, S-rT3 remained unchanged and S-cortisol increased significantly (p less than 0.01). No correlation was found between S-T3 and S-cortisol. An association was found between S-T3 and blood glucose (p less than 0.05). An acute low S-T3 was achieved by depressing the peripheral availability and utilization of glucose. No association to a simultaneous increase in S-cortisol was found. An increase in S-rT3 failed to appear, probably also due to glucopenia.

One disadvantage of the TRH test is that an absent or blunted TSH response is seen not only in hyperthyroid patients but also in some normal subjects. The aim of the present study was to elucidate whether the discriminatory power between eu- and hyperthyroidism could be increased by determining the T3 and T4 levels before and after the TRH administration. The study population consists of 30 patients referred for evaluation of suspected hyperthyroidism. The results show that all but one of the patients (n=20) who had T3 levels within the normal reference limits increased these levels after TRH administration, whether their TSH response was normal or blunted. One patient's T3 levels decreased after TRH. All the patients (n=10) who had T3 levels within the hyperthyroid range showed a decrease after TRH. The decrease was significantly correlated (r=0.90) to the magnitude of the increase. No consistent T4 and no change in reverse-T3 response was obtained. The addition of T3, T4 or reverse-T3 determinations in connection with the TRH test does not seem to increase the discriminatory power of the test.

Severe hypercalcemia recurred three times during an observation period of 15 years in a woman with anorexia nervosa. The patient displayed a factitious cheese-alkalosis syndrome similar to the iatrogenic milk-alkali syndrome.

The aim of the study was to determine whether the addition of T3 and T4 determination in connection with a routine TRH-test could increase the discriminatory power of the test. Thus, forty-one patients with suspect hyperthyroidism were examined and samples for T3 and T4 and TSH determinations were drawn prior to the administration of TRH and at 20 and 60 min thereafter. The results showed that the addition of these thyroid hormone estimations did not increase the clinical value of the TRH-test.

To test whether chronic thyroid hormone excess influences the hypothalamic-pituitary-testicular axis, 8 hyperthyroid men were given two identical intravenous GnRH tests. The first test was performed before any treatment had been instituted, the second 6-13 months later, when medical treatment had made the patients euthyroid. Although basal serum luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone (T) levels were of similar magnitudes before and after the medical treatment, LH and FSH responsiveness to gonadotropin-releasing hormone (GnRH), as reflected by the hormone incremental areas (U/l X min), were significantly larger in the thyrotoxic state compared with the euthyroid state (LH incremental areas: 3,999 +/- 665 vs. 2,640 +/- 430, p less than 0.02; FSH incremental areas: 825 +/- 193 vs. 542 +/- 98, p less than 0.05). Furthermore, serum T increased significantly in response to GnRH when the patients were hyperthyroid (T incremental area: 162 +/- 51, p less than 0.02), but failed to do so when they were euthyroid (T incremental area: 92 +/- 53, NS). These results imply that chronic thyroid hormone excess makes the pituitary gonadotrophs 'hypersensitive' to exogenous GnRH. This may in turn explain why human Leydig cells respond more powerful to exogenous GnRH in thyrotoxic patients than in euthyroid subjects.