Determination of free thyroxine in serum of patients with cirrhosis of the liver

The interpretation of the serum protein-bound iodine: A review

The effects of physiological and environmental factors, of thyroid and non-thyroid diseases, and of drugs on the serum protein-bound iodine are described and discussed.

The thermogenic and metabolic effects of food in liver cirrhosis: consequences on the storage of nutrients and the hormonal counterregulatory response

The thermogenic effect of food and the rates of oxidation and storage of nutrients were evaluated by indirect calorimetry in 10 cirrhotic patients and seven normal controls for a 6-hour period, after they had consumed a standard meal supplying 15 kcal/kg body weight with 15%, 30%, and 55% protein, fat, and carbohydrate calories, respectively. Although the thermogenic response to food was not significantly lower in patients than in controls (51.6 +/- 13.5 v 72.2 +/- 8.8 kcal/6 h), patients exhibited a delayed and blunted increment of energy expenditure after the meal intake (P less than .025). The greater part of the glucose load was oxidized in patients (70.2 +/- 3.9% v 50.4 +/- 3.9% in controls; P less than .01), suggesting a defective glucose storage as glycogen. This result could be related to insulin resistance, which was evidenced by a large increase in glucose and insulin levels after the meal intake in patients (P +/- .001). Conversely, lipid oxidation was sharply reduced and de novo lipogenesis occurred in patients, so that the rate of lipid storage was increased. The profiles of circulating levels of catecholamines, thyroid hormones (free thyroxine [FT4] and triiodothyronine [T3]), and glucagon were assayed during the test. Norepinephrine and glucagon levels remained higher in patients throughout the test (P less than .001), whereas thyroid hormones stayed in the same range in the two groups. After an initial increase, glucose levels decreased sharply, inducing an activation of counterregulatory hormones, glucagon, and notably, epinephrine, for which the increment was correlated with the decrease of glucose (r = -.917; P less than .001).(ABSTRACT TRUNCATED AT 250 WORDS)

Thyroid and pituitary hormone responses to TRH in advanced nonalcoholic liver disease

Basal T4, T3, TSH, prolactin and growth hormone levels were determined in several groups: patients with postnecrotic cirrhosis with hepatocellular carcinoma (n = 14); patients with postnecrotic cirrhosis but without hepatocellular carcinoma (n = 26); cholangiolar carcinoma (n = 9); and normal controls age-matched to within 5 yr of the liver disease subjects studied. In addition, TRH stimulation (400 micrograms TRH) was performed; TSH, prolactin and growth hormone responses over a 180-min time interval were evaluated for each subject. The responses observed varied between liver disease groups. The presence or absence of hepatocellular carcinoma was found to determine, at least in part, the type of response observed. Similarly, the presence or absence of hepatic encephalopathy determined, and/or reflected, at least in part, the type of response observed. Finally, for purposes of continuity, basal and TRH-stimulated levels of TSH, prolactin, growth hormone, T4 and T3 are compared in 3 settings of cirrhosis: alcoholic, nonalcoholic postnecrotic cirrhosis, and postnecrotic cirrhosis with hepatocellular carcinoma.

A new method for the measurement of acute alterations in thyroxine deiodination rate in man

A newly devised dual labeled iodine isotopic method is described for the detection and quantitation of alterations in thyroxine (T(4)) deiodination rate in man. This method employs the principle of a constant (125)I infusion to serve as a reference source for the generation of (131)I derived from the deiodination of T(4)-(131)I. Measurement of these two iodide isotopes are made in serially timed urine collections and are expressed in terms of a ratio value. Using this technique, it was possible to measure accurately the effects of a single dose of 6-propylthiouracil (6-PTU) in producing inhibition of T(4) deiodination in euthyroid subjects. It was also possible to assess the time of onset, duration of action, and degree of inhibition produced by 6-PTU. Employing single doses of 6-PTU, ranging from 100 to 1000 mg, there was found to be a log dose relationship with a degree of inhibition observed in T(4) deiodination. In control studies T(4) deiodination rate was found to be constant for periods ranging up to 72 hr in normal ambulating subjects. The acute administration of many other agents was employed in an attempt to alter the T(4) deiodination rate. These included diphenylhydantoin, methimazole, triiodothyronine, thyroxine, thyroid stimulating hormone (TSH), adrenocorticotropin (ACTH), hydrocortisone, predinsolone, potassium iodide, epinephrine, and oxytocin. No detectable change in T(4) deiodination rate was observed with these agents in the dosage ranges employed in this study. The lack of any observable alteration in the T(4) deiodination rate in response to this array of drugs and hormones appears to indicate that the availability of T(4) to intracellular sites of deiodination and possibly action is well modulated to resist abrupt changes.