Effect of thyroid function on serum somatomedin activity

To obtain more information about a possible role of somatomedins in mediating the effects of thyroid hormones on the development and function of epiphyseal cartilage, somatomedin activity, measured on the basis of 35S incorporation in embryonic chick cartilage, was studied in thyrotoxic patients before and after treatment with carbimazole or surgery and in a group of patients with primary hypothyroidism. In 29 hyperthyroid patients mean values of somatomedin were 1.29 +/- 0.03 SEM an differed significantly (P less than 0.01) from normals (1.04 +/- 0.03). In 15 carbimazole treated patients and in 5 operated patients with thyrotoxicosis somatomedin levels fell from 1.29 +/- 0.04 to 1.03 +/- 0.04 (P less than 0.01) when the patients became euthyroid. Correspondingly, somatomedin levels in 12 untreated hypothyroid patients (0.82 +/- 0.04) were significantly less than in normals (P less than 0.01) an increased from 0.77 +/- 0.09 to 1.14 +/- 0.13 (P less than 0.05) in 4 patients on replacement therapy.

IN CONCLUSION

somatomedin levels rise when thyroid hormones are present in excess, and fall when these are deficient. This suggests that thyroid hormones are important regulators of somatomedin levels.

Effects of total fasting in obese women. IV. Response of serum triiodothyronine (T3) and reverse triiodothyronine (rT3) to administered T3

Serum levels of T4, T3, rT3, RT3U and TSH were estimated in 12 obese women in the course of a 14-day fasting. Seven of these patients were treated with T3 in a daily dose of 60--80 micrograms. Fasting led to a small increase of serum T4, while fasting combined with T3 administration was accompanied by a small decrease of serum T4. Serum T3 decreased in the course of the first 2 days of fasting to 40--50% of initial values and remained at this low level up to the 15th day of fasting. In the T3 treated group a prompt increase of serum T3 was recorded (+80%), followed by a steady decrease, reaching the control values on day 15, in spite of a continuous T3 administration. Serum rT3 in the untreated fasting group steadily increased up to the 12th day (+43%) and then dropped below the control value (-28%). In the treated group after a non-significant increase (+22%), a decrease of serum rT3 was also observed (-42%). Fasting was accompanied by a tendency to increased serum RT3U values, in the T3 treated group no change occurred. TSH in the untreated fasting women remained practically unchanged while T3 administration was accompanied by a tendency to a transient decrease. The heart rate showed a non-significant tendency to increase in the T3 treated group and the last week of fasting was also accompanied in several patients by a larger weight loss. These results suggest that in addition to an enhanced synthesis of rT3 to the detriment of a decreased production of T3 from T4, an increased catabolism of administered T3 and of endogenous rT3 is involved in a strict calorie restriction. An abortive T3-TRH-TSH feed-back may also operate in these conditions.

Effects of single intramuscular administration of various preparations of corticosteroids on bentonite-induced oedema of rat hind paw

Effects of single prophylactic and/or therapeutic i.m. doses of various esters of anti-inflammatory steroids on the bentonite-induced oedema of the rat paw were followed. The short-lasting actions (1 d) of soluble sodium succinate esters of hydrocortisone, prednisolone and 6-methylprednisolone on the one hand, and the long-lasting actions (1 to 2 weeks) of insoluble hydrocortisone acetate, 6-methylprednisolone acetate or cyclopentylpropionate, and triamcinolone diacetate or acetonide on the other hand have been proved. Both the preparations of beta-methasone tested exerted short-lasting effects (1 d). It has been confirmed that triamcinolone acetonide is more effective (and also more toxic) than the diacetate ester of this steroid. The bentonite-induced oedema has proved to be a suitable model of inflammatory reaction for screening anti-inflammatory corticosteroids because it makes possible the determination and differentiation of the time of onset, intensity and duration of action of single doses of various pharmaceutical formulations of these agents.

["Giant" oncocytic renal adenomas]

Postmortem and bioptic material from the 1953-1976 period included 7 cases of oncocytic renal adenoma larger than 5 cm including 3 larger than 10 cm. Macroscopic characteristics included red-brownish coloration and extensive foci of central hyalinosis. Microscopy showed them as being made up of cells resembling oncocytes with relatively active nuclei with solid, occasionally focus-like tubular structure. In spite of the large size and, in some rarer cases, focal nuclear atypia all of the tumours appeared to behave in a benign way. The causes of their increased frequency in the past decade remain to be clarified yet.

Bone isoenzyme of serum alkaline phosphatase in acromegaly

In 37 patients with active acromegaly and in 15 patients with inactive acromegaly, activity of bone isoenzyme of serum alkaline phosphatase correlated (P less than 0.001) with serum concentration of immunoreactive growth hormone. By using stepwise regression analysis, the predication of serum growth hormone values based on serum levels of bone isoenzyme of serum alkaline phosphatase, gamma-glutamyl transferase and calcium in these patients with acromegaly was within 1 S.D. range in 37 patients and in only 2 patients was it out of 2 S.D. range. By using discriminant analysis, based on bone and liver isoenzymes of serum alaline phosphatase and urinary hydroxyproline excretion, 87%, 60% and 97% of the classification of patients with active and inactive acromegaly and healthy adults, respectively, was correct. The multivariate approach offers a quantitative appraisal of the biochemical parameters of peripheral growth hormone action used as an indicator of growth hormone concentration in patients with acromegaly.

Relationship of the activity of the bone isoenzyme of serum alkaline phosphatase to urinary hydroxyproline excretion in metabolic and neoplastic bone diseases

A significant correlation between the activity of the bone isoenzyme or serum alkaline phosphatase and the urinary hydroxyproline excretion in osteomalacia, osteoporosis, primary hyperparathyroidism with osteodystrophy, Paget's disease, secondary bone tumours, and in a control group was found (P less than 0.001). This close correlation was not observed between these variables in patients with active acromegaly. Diagnosis determined from these indices of formation and turnover of bone matrix agreed with that established by histological and histochemical examination of bone, by X-ray investigation of the skeleton, and by the radionuclear 85Sr test. The relationship between the activity of bone isoenzyme and urinary hydroxyproline excretion differed in metabolic bone diseases with a high bone turnover, in patients with osteoporosis and in patients with early osteoclastic bone metastases.

Ten-year experience with DDAVP in treatment of diabetes insipidus

Thirty patients with central diabetes insipidus were treated with 1-deamino-9-D-arginine vasopressin (DDAVP) during the period of 3--10 years. DDAVP was applicated in 1--3 intranasal doses daily. The dosage varied between 7--42 microgram/24 h. The diuresis before the treatment ranged between 28,000--7,600 ml/24 h (mean 13,883 ml/24 h) and was decreased by DDAVP below 2000 ml/24 h in 21 patients (70%) and to 2000--4000 ml/24 h in 8 patients (26.6%). In a single case it was not possible to reduce the diuresis from 20,000 ml below 8,000 ml/24 h. Favourable properties of DDAVP: absence of reduction of potency, lack of important side-effects and prolonged action were not lost even in the course of the long term treatment. No harmful effects of DDAVP were noted. Blood count as well as renal function tests were not affected by the treatment. All the patients preferred DDAVP to their previous therapy.

Influence of single peroral dose of aminoglutethimide on the rat adrenal cortex

In female albino rats force fed with a single dose of 50 mg of aminoglutethimide (AG) lipoid adrenocortical hyperplasia was found within 24 h. In addition, a marked focal increase in cytoplasmic transparency was found which ultrastructurally appeared to result from optically empty vacuoles and membrane-bound spaces. Later, an increase occurred in the translucency of the cytoplasmic matrix, mitochondrial swelling, destruction of cell membranes and disappearance of adrenocortical cells presenting as cytolysis. Some of the damaged cortical cells contained protein vacuoles with fibrillar structures and occasionally also blood cells. All such changes were associated with a marked infiltration by neutrophilic granulocytes, the most severe of them resembling an acute purulent epinephritis. Ultrastructural examination showed blood monocytes with signs of initial phagocytic activity at sites of disintegration of adrenocortical cells. Focal decrease of dehydrogenase activity was demonstrated in areas of cellular destruction, while no alteration in acid phosphatase activity was detected. Moreover, an absolute increase in corticosterone production form endogeneous precursors in vitro was found which could be partially explained by an increase in adrenocortical size. Formation of 18-hydroxycorticosterone and aldosterone from 4-14C-progesterone was decreased. However, no appreciable changes were revealed in the zona glomerulosa. From these findings it may be assumed that high doses of AG not only block the conversion of cholesterol into pregnenolone, but also injure some other cellular enzymatic systems necessary for the integrity of the adrenocortical cell.

Inhibitory effect of various cytostatics and cycloheximide on acute experimental pancreatitis in rats

Cycloheximide, 5-azacytidine, and 4-methoxybenzoyl-beta-bromoarylate (Cytembena) block the development of experimental acute pancreatitis in rats when mediated by the administration of 5% bile solution into the pancreas in vivo. Six hours after drug treatment the pathological changes, evaluated macroscopically or using histological sections of the pancreas, were significantly decreased. The drugs affected the amount of abdominal fluid and lowered its lipase and amylase activity. The known inhibitory mechanism of the active drugs and the possible advantage of cycloheximide for clinical use are briefly mentioned.

[Functionally active tumor of the carotid body]

The clinical and biochemical pictures of a woman of 60 suffering from paroxysmal hypertension appeared to be clear evidence of a functionally active neoplasm of the sympathoadrenal tissue. A surgical operation ruled out the possibility of the tumour being localized adrenally so that the actual site of noradrenaline release was never found during the patient's lifetime. An autopsy discovered the presence of a carotid body tumor sized. 4.5X3X3 cm. The histological picture, electron microscopy as well as the positive isolation of noradrenalin all seemed to offer clear evidence of a functionally active tumour although the chromaffin reaction was negative. This is just additional evidence of the fact that the carotid body does belong among sympathetic paraganglia and that the chromaffin reaction is not sufficiently sensitive and reliable either for the determination of biogenic amines in the tissue or for a clear, unequivocal detection of functionally active tumours of the sympathetic.

Ultrastructural changes of the adrenal cortex in Cushing's syndrome treated with aminoglutethimide (Elipten Ciba)

The main ultrastructural feature of human adrenal cortices following administration of aminoglutethimide (Elipten CIBA), a steroid biosynthesis blocking agent, is a striking intracellular accumulation of lipids, also seen in the light microscopy. The lipids accumulate in the adrenocortical cells but are also stored in the cytoplasm of pericapillary histiocytes. The lipids are present in the adrenocortical cells mostly as rounded liposomes of variable size, whereas those in the histiocytes usually show up as an amorphous debris with abundant myelin figures and cholesterol crystals. In some areas of the adrenal cortex activated histiocytes changing into lipophages may become the prevalent cell. They also take the place of destroyed adrenocortical cells and can form compact cell aggregates of variable size or even columnar strands between neighbouring capillaries, thus resembling columns of adrenocortical cells. In some of the adrenocortical cells focal cytoplasmic degradation, turning into coagulation necrosis, was observed. In others initial cytolysis was found. In contrast with earlier findings in experimental animals, mitochondrial changes in humans were not a prominent feature. The only changes occasionally observed were a focal disappearance of the vesicular cristae and a concomitant fibrillary loosening of the mitochondrial matrix.

Lysolecithin-dependent release of cholesterol from rat plasma

We studied the effect of lysolecithin on the clearing of plasma cholesterol. The immediate and maximal conversion of plasma lecithin to lysolecithin was produced in rats by intravenous injection of phospholipase A. The changes which took place in the converted lysolecithin and of cholesterol were followed in rats which had previously received [32-P]phosphate and [14-C]cholesterol. We followed simultaneously the in vitro changes in blood removed immediately after the in vivo administration of phospholipase A. The experiments showed that a substantial part of the plasma lecithin was converted to lysolecithin within the first minute after intravenous administration of phospholipase A. In the course of 60 min of blood incubation, the ratio of plasmatic lysolecithin in the closed system continued to increase. At the same time the content of cholesterol also increased. In vivo, the converted lysolecithin was quickly released from the plasma, so that within 10 min the original lecithin content dropped to 15-5% depending on the dose of phospholipase A that had been administered. The content of sphingomyelin and lysolecithin, which increased only temporarily shortly after injection, did not alter during the experiment. The level of plasma cholesterol esters, however, dropped significantly, whereas the free cholesterol content increased. The molar ratio of the drop in lipid phosphorus and cholesterol esters in plasma after the administration of phospholipase A was similar. A significantly higher cholesterol content was found in the liver of animals treated with phospholipase A.