Effect of estrogens on thyroid function. II. Alterations in plasma thyroid hormone levels and their metabolism.

The circulating levels of total triiodothyronine (TT₃), thyroxine (TT₄, and T₄-bbinding globulin (TBG) and the kinetics of T₃ and T₄ were studied in five menstruating rhesus monkeys before, during, and after prolonged treatment with estradiol monobenzoate (E₂B, 50 μg/kg body weight/day subcutaneously). A significant increase over pretreatment (p < 0.01) plasma TT₃, TT₄, and TBG was recorded on day 6 of E₂B therapy. A further significant stepwise increase in these parameters was noted up to day 19 of E₂B, when the levels plateaued for the rest of the period of E₂B treatment. Two weeks after discontinuation of E₂B, plasma TT₃, TT₄, and TBG had returned to the pretreatment range and remained so up to 40 days of observation. Although the percent free T₃ and percent free T₄ were significantly decreased (p < 0.01) during E₂B therapy, the absolute concentrations of free T₃ and free T₄ were not altered. After prolonged E₂B treatment the metabolic clearance rate, distribution space, and production rate (PR) of both T₃ and T₄ were decreased (p < 0.01). The extrathyroidal T₄ pool (ETT₄P) was significantly increased (p < 0.01), whereas ETT₃P did not show any significant alterations (p > 0.05). The decreased PR of T₄ might have been due to a direct inhibitory effect of E₂B on the thyroid, whereas the decrease in PR of T₃ might have been due to either decreased conversion of T₄ to T₃, to decreased secretion by the thyroid, or both.     

Orthostatic hypertension.

A 40 year old man was found to have marked hypertension when he was in the upright position with normal pressures when he was supine. Investigations disclosed normal catecholamine and renin levels. The baroreceptor reflex was somewhat depressed. The mechanism of this orthostatic hypertension is not known. The condition has not been reported previously.     

Glucose concentration and insulin release in 5-thio-D-glucose-treated mice

Male albino mice were given a single dose of various concentrations (25, 50, and 100 mg/kg body weight) of 5-thio- -glucose or daily infusions (33 mg/kg body weight) of 5-thio- -glucose for 21 days. Elevated blood glucose and immunoreactive insulin (IRI) levels were observed in the mice treated with 5-thio- -glucose. Fasting glucose levels reached a maximum in 30 minutes and IRI levels reached a maximum in 60 to 90 minutes in the single-dose treated animals compared to preintubation levels. In the mice treated for 21 days, the fasting and fed glucose and IRI levels were significantly increased. Single dose of glucose (1 g/kg body weight) given to fasting and fed mice did not alter the glucose and IRI levels in the treated animals. However, a single dose of 5-thio- -glucose (33 mg/kg body weight) given to fasting and fed treated animals increased the IRI levels significantly but not the glucose concentration. These data show that both single-dose and 3-week treatment with 5-thio- -glucose produced a hyperinsulinemic diabetes in male albino mice.     

Packed cells,platelet-rich plasma,and adenosine diphosphate in the production of occlusive vascular changes in lungs of rabbits

An experimental study to simulate the lesions of primary pulmonary hypertension was undertaken in rabbits. Five groups were made, each having six animals and these were given separately packed cells (3 per cent suspension of homologous erythrocytes in physiologic saline), plasma rich in platelets, plasma without platelets, ADP solution, and normal saline injections biweekly for a period of three months. Clinical, electrocardiographic, and histologic examination of the lungs were made. It was noted that animals given packed cells, plasma rich in platelets, and ADP solution developed electrocardiographic changes and histologic lesions in the lungs suggestive of pulmonary hypertension.     

Effects of labetalol on left ventricular mass and function in hypertension--an assessment by serial echocardiography

We determined echocardiographic (M-mode) indices of left ventricular mass and function serially at 1-month intervals in 10 patients with uncomplicated mild or moderate essential hypertension, before and after adequate control of blood pressure with labetalol, a combined alpha- and beta-receptor blocking agent. Seven patients had pretreatment echocardiographic evidence of left ventricular hypertrophy with disproportionate septal thickness in 4. Systolic blood pressure in the untreated state correlated well (r = 0.96) with left ventricular mass but poorly (r = 0.30) with diastolic pressure. Following a satisfactory blood pressure reduction, achieved in all patients, left ventricular mass decreased from 240.5 +/- 71.1 g to 159.5 +/- 40.7 g (P less than 0.01), interventricular septal thickness from 1.33 +/- 0.3 cm to 0.92 +/- 0.25 cm (P less than 0.01) and posterior wall thickness from 1.03 +/- 0.23 cm to 0.93 +/- 0.23 cm (P less than 0.05). While the maximum changes in left ventricular mass were noted by the end of first month (P less than 0.01) with insignificant changes thereafter, the correlation of fall in blood pressure with change in left ventricular mass was significant only after 2 months of treatment (P less than 0.05). Indices of left ventricular function (end-diastolic volume, ejection fraction, fractional diameter shortening, left atrial dimension and posterior aortic wall motion) were normal before treatment and remained unchanged during 3 months of treatment. In this short-term study, labetalol reduced left ventricular hypertrophy (expressed as left ventricular mass and wall thickness) without altering left ventricular function indices in patients with uncomplicated essential hypertension. This has important implications in the treatment of hypertensive patients.     

Thyroid function in changing weather in a subtropical region

Serum and 24-hr urine samples were collected on 2 consecutive days during the first week of each month for 1 yr from eight healthy euthyroid men aged 25–37 yr. The means of minimum and maximum environmental temperature for the 30 days period preceding the sample collection represented the temperature for that month. Total serum thyroxine (T₄), triiodothyronine (T₃), thyrotropin (TSH), and urinary T₃ and T₄ were measured by specific radioimmunoassays and serum thyroxine-binding globulin (TBG) by the radioligand binding assay. The serum TSH and urinary T₃ and T₄ responses to 100 μg intravenous TRH were studied in five subjects during summer and again during winter. The serum concentration of these hormones and TBG did not reveal significant variations throughout the year. However, the mean urinary excretion of both T₃ and T₄ during coldest months (January and February), at 0.97 and $\text{1.95 μ}\text{g}\text{24 hr}$, respectively, were significantly higher than the corresponding values (T₃, 0.48; T₄, $\text{1.18 μ}\text{g}\text{24 hr}$) during the hottest months (May–July). The TSH, and urinary T₃ and T₄ responses to identical doses of TRH during summer and winter did not differ significantly. Since urinary T₃ and T₄ indirectly reflect the prevailing unbound serum levels of these hormones, it is likely that the greater availability of free and biologically active thyroid hormones could help the body to adapt to cold by increasing nonshivering thermogenesis.     

Catabolism of apoprotein A-1 of HDL in normal and nephrotic rats

High density lipoprotein was isolated from the plasma of control and puromycin aminonucleoside nephrotic rats and labeled with ¹²⁵I. It was injected into control and nephrotic rats and the plasma analyzed after 3 min, 5 hr, and 20 hr. High density lipoprotein was isolated and the specific activity of apo A-I determined following apoprotein separation using SDS-polyacrylamide gel electrophoresis. The distribution of labeled apoproteins was determined in whole plasma by SDS-gel filtration column chromatography and the plasma concentration of apo A-I was calculated from its specific activity and the total plasma apo A-I radioactivity. A 3 min to 5 or 20 hr fractional catabolic rate was calculated. When multiplied by the plasma concentration of apo A-I, an estimate of the absolute catabolic rate was obtained. When injected into normal animals, the high density lipoprotein apo A-I had similar catabolic rates whether derived from control or nephrotic rat plasma, averaging 65 and 48 μg of apoprotein per ml of plasma per hr at 5 or 20 hr, respectively. Labeled HDL was injected into nephrotic rats of varying degrees of severity. The moderately nephrotic rats with plasma cholesterol levels averaging 177 mg/dl had apo A-I levels that were 3.6 times that of controls (1799 ± 195 μg/ml) and 2.4-fold increases in apo A-I catabolic rates (134 ± 28.9 μg/ml plasma/hr). The severely nephrotic rats with cholesterol concentrations averaging 396 mg/dl had apo A-I levels 7.1 times that of the controls (3533 ± 220 μg/ml) while the catabolic rate was 2.7 times the control rate (153 ± 19.5 μg/ml/hr), which was not a significant increase beyond that of the moderately nephrotic group. It was concluded that compositional differences of HDL resulting in an increased proportion of apo A-I, as in nephrotic rat plasma, do not affect apo A-I metabolism. The high levels of apo A-I in the plasma of nephrotic rats is due to increased hepatic synthesis that results in an expansion of the pool size and saturation of catabolic pathways. Small increases in apo A-I synthesis lead to large increases in the plasma concentration, an observation that may be important in the regulation of HDL levels that are known to be correlated with a decreased incidence of atherosclerosis.     

Elevated fetal chromosomal damage in malnourished pregnant rats

Cytogenetic studies in fetal cells from pregnant rats given a protein-restricted diet revealed a significant induction of structural chromosomal aberrations and sister chromatid exchanges.     

Selective urinary excretion of phosphatidyl ethanolamine in patients with chronic glomerular diseases

Urinary phospholipids and lipoproteins in chronic glomerular diseases were analyzed. The subjects used were 26 patients consisting of 14 with chronic glomerulonephritis and 12 with nephrotic syndrome. Nine healthy normals served as controls. Phospholipids were isolated by one-dimensional thin-layer chromatography (TLC) using an internal standard for quantification and partially by two-dimensional TLC and, furthermore, quantified by two different methods to ascertain the kinds of phospholipids. Urinary lipoproteins were isolated by density gradient ultracentrifugation and analyzed by electrophoresis. The urinary excretion of phosphatidyl ethanolamine (PE) was recognized exclusively in the patient group and that of phosphatidyl serine (PS) in most cases with nephrotic syndrome. The daily urinary PE excretion rate was closely correlated to the urinary albumin excretion rate. However, phosphatidyl choline (PC) and sphingomyelin (SPH), which are main phospholipids in serum and red blood cell membranes, in most cases were hardly detected in urine. These observations were confirmed by two-dimensional TLC using valuable spot tests for identification of phospholipids and also by the two different quantification methods. In density gradient ultracentrifugation, urinary lipoproteins did not form such peaks as seen in the profiles of serum lipoproteins. The presence of urinary lipoproteins in two nephrotic patients has been shown, but although the method used was not very sensitive, it was suggested that lipoproteins were hardly excreted into urine as the lipoprotein deficient fraction (LPDF) (d > 1.21 g/ml), in which albumin is predominant. PE was found mainly in LPDF of urine, although the amount of PE in urinary lipoproteins was very limited. These data gave a basis for a postulate that the urinary excretion of PE may not be related to the excretion of lipoproteins but to LPDF albumins. From the practical absence of PC and SPH in urine, it was further postulated that choline-containing phospholipids (PC, SPH) may not have been excreted in sufficient quantities in these patients.     

Glucose-dependent insulin inhibition of ketone body formation from long-chain fatty acids in the perfused livers of fasted rats

The data presented in this report show a direct effect of insulin on impairment of ketone body production in perfused livers from fasted rats. The data also show that physiologic levels of insulin alone or glucose alone are not sufficient to cause an impairment in ketogenesis. Only when insulin and glucose are both present at levels seen in infected rats is ketone body production impaired.     

Multiple forms of acid phosphatase activity in Gaucher's disease.

Although the primary genetic defect in all individuals with Gaucher's disease is a deficiency in glucocerebrosidase activity, the finding of marked elevations in splenic and serum acid phosphatase activity is almost as consistent a finding. Gaucher spleen and serum contain at least two forms of acid phosphatase that can be readily separated by chromatography on columns containing the cation exchange resin Sulphopropyl Sephadex. The major species of acid phosphatase (designated SP-I) contained in Triton X-100 (1% v/v) extracts of Gaucher spleen accounts for 65%--95% of the total activity and has the following properties: (1) it does not bind to the cation exchange column; (2) it exhibitis a pH optimum of 4.5--5.0; (3) it is inhibited by sodium fluoride (15 mM), L(+)-tartaric acid (20 mM), and beta-mercaptoethanol (2.1 M), and (4) it is resistant to inhibition by sodium dithionite (10 mM). The minor acid phosphatase activity (designated SP-II) present in extracts of Gaucher spleen has properties similar to those of the major species of acid phosphatase activity contained in serum from patients with Gaucher's disease: (1) it binds firmly to cation exchange columns (eluted by 0.5 M sodium chloride); (2) it exhibits a pH optimum of 5.0--6.0; (3) it is inhibited by sodium fluoride and sodium dithionite; and (4) it is resistant to inhibition by beta-mercaptoethanol (2.1 M) and L(+)-tartaric acid (20 mM). In addition, a second form of acid phosphatase that is tartrate resistant was found to be elevated in Gaucher serum. This form of serum acid phosphatase did not bind to Sulphopropyl Sephadex, was found to be significantly resistant to beta-mercaptoethanol (2.1 M), and was only partially inhibited by sodium dithionite (10 mM). The findings reported here indicate that at least three distinct forms of acid phosphatase activity are elevated in Gaucher's disease. Furthermore, the minor acid phosphatase activity contained in spleen homogenates has properties very similar to those of the major acid phosphatase activity observed to be present in serum of patients with Gaucher's disease. These data indicate that simple spleen spillage cannot account for the increased levels of serum acid phosphatase in patients with Gaucher's disease.     

SCE frequency in malnourished mice

The effect of induced protein deficiency on sister chromatid exchange (SCE) frequency in experimental protein energy malnutrition (PEM) was investigated. Malnourished mice exhibited significantly elevated SCE levels in their bone marrow cells. A step-wise increase in this frequency was also observed with decreasing protein content.     

Inappropriately low serum GH in an acromegalic: Lysosomal involvement in intracellular hormone degradation

A patient with galactorrhea, amenorrhea and severe acromegaly was found to have a large pituitary adenoma. In view of the severity of the disease the serum growth hormone (GH) level (22.5 mlU/liter) was considered inappropriately low. Tissue from the adenoma was obtained during successful treatment with interstitial irradiation (⁹⁰Yttrium). Trypsindispersed biopsy cells in culture for 12 days secreted low amounts of GH compared to the same number of adenoma cells from 5 other unselected acromegalics or a normal pituitary. No other hormones were secreted in culture. Immunocytochemical staining was positive only with GH antisera but showed low intracellular content. This was confirmed by direct analysis of the tumor tissue which showed the GH content to be only 20% of that found in 5 normal pituitaries and 4% of that found in 8 other adenomas from acromegalics. Electron microscopy showed a striking appearance, with GH secretory granules that were sparse in number, smaller than usual, and in the main arranged around numerous intracellular profiles with double membranes and low electron density that were tentatively identified as autophagic vacuoles (secondary lysosomes). Subcellular fractionation showed the distribution of the radioimmunoassayable GH in the gradient to be coincident with the peak of the lysosomes whereas in 2 other acromegalics the GH peak was clearly separated from the lysosomes. We conclude that the simultaneous appearance in our patient of a relatively low serum GH together with a large tumor and severe acromegaly can be explained biochemically by the striking finding of crinophagy - disposal of hormone secretory granules within the somatotroph cells themselves.     

Metabolism of protein, amino acids, and glucose and their response to insulin in atria and cardiac myocytes of traumatized rats

Soft tissue injury to one hindlimb of rats was used to test the metabolic response of atrial and ventricular muscle to trauma. Effects of insulin on muscle metabolism were also studied. In myocytes and atria from normal animals, insulin increased protein synthesis and decreased protein degradation. For myocytes of rats at one and two days after trauma, this effect of insulin on proteolysis could not be detected. Over the next two days, the inhibitory effect returned to normal. Insulin also did not increase protein synthesis on day 1, but did thereafter. In atria, in contrast to heart cells, the inhibitory effect of insulin on proteolysis was enhanced at two and three days after trauma, and its stimulation of protein synthesis was unaltered. Insulin increased carbohydrate metabolism in both myocytes and atria of normal rats and traumatized rats after 2 days, and trauma did not alter this response. In myocytes, but not atria, trauma led to a faster oxidation of leucine and a significant rise in the production of alanine. Production of glutamine and glutamate was not affected in either tissue. These results show that the metabolic responses to trauma of atrial and ventricular muscle differ considerably.     

Adverse effects of fructose in perfused livers of diabetic rats

Livers isolated from both fed normal and alloxan diabetic rats were perfused for 30 min using Krebs-Henseleit bicarbonate blood buffer medium followed by 10 min flow-through infusions with either 5 mM or 28 mM fructose concentrations. In livers of normal and diabetic rats, both 5 mM and 28 mM fructose concentrations produced an elevation in tissue cyclic AMP levels, activation of glycogen phosphorylase, increased protein kinase activity, decreased tissue ATP levels, large increases in tissue fructose-1-phosphate, and variable effects upon glycogen synthase. These results are consistent with previously reported cyclic AMP mediated activation of glycogen phosphorylase by fructose via protein kinase in normal rat liver. In addition, both 5 mM and 28 mM fructose infusion resulted in large decreases in normal and diabetic synthase phosphatase activity. Therefore, these results in both normal and diabetic livers are inconsistent with a direct beneficial effect of fructose in the isolated perfused rat liver.     

Catabolism of branched-chain amino acids by diaphragm muscles of fasted and diabetic rats

In vitro catabolism of branched-chain amino acids, leucine and valine, was investigated using diaphragm muscles from normal, streptozotocin-diabetic and overnight fasted rats. Oxidation and transamination of [1-14C] branched-chain amino acids were both stimulated to a similar extent by diabetes or fasting, when diaphragms were incubated with glucose. Transamination of leucine and valine was increased when diaphragms were incubated with pyruvate; stimulation of transamination was greatest in diaphragms from diabetic rats. Leucine and valine oxidation by control diaphragms was inhibited by pyruvate while it was unchanged or slightly stimulated in diaphragms from fasted or diabetic rats. Thus diaphragms from diabetic rats oxidized two to threefold more branched-chain amino acids than controls when they were incubated with pyruvate. The specific radioactivity of extracellular alpha-ketoisocaproate (KIC; the product of leucine transamination) produced by diaphragms incubated with [14C]leucine was similar for all groups (fed, fasted, or diabetic) in the presence or absence of pyruvate. Oxidation of [1-14C]KIC by diaphragms from fasted or diabetic rats, incubated with glucose, was the same or less than KIC oxidation by control diaphragms. Incubation with pyruvate inhibited KIC oxidation by control diaphragms to a significantly greater degree than that by diaphragms from diabetic or fasted rats. These data suggest the following Flux through branched-chain amino acid transaminase is limited by the availability of amino group acceptors in diaphragms from normal and overnight fasted rats, and to a greater extent in diaphragms from diabetic rats. Flux through the transaminase may be a major determinant of accelerated branched-chain amino acid oxidation by diaphragms in fasting and diabetes. In diaphragms of fasted and diabetic rats, flux through the branched-chain alpha-ketoacid dehydrogenase complex is resistant to inhibition by pyruvate, which is normally observed in controls.     

Diagnosis of ileocecal and colonic tuberculosis by colonoscopy

The colonoscopic findings in 11 proven cases of ileocecal tuberculosis consisted of deformed ileocecal valve in all 11 and contracted cecal lumen in 10. This was associated with mucosal nodules predominantly around the ileocecal valve, pseudopolypoid folds, and mucosal protuberance. Two patients had an isolated cecal ulcer. In three of the 11 patients the examination enabled a histologic diagnosis to be made on the basis of typical granuloma. In the other four patients Mycobacterium tuberculosis was isolated from the tissue obtained through biopsies.     

Action of L-epinephrine on the renin-aldosterone system and on urinary electrolyte excretion in man

The effect of L-epinephrine infusions (0.5–6.5 μg/min for up to 24 hr) in recumbency, on the renin-aldosterone system was studied in normal volunteers on diets containing 200 mEq sodium. Urinary sodium excretion was increased, potassium excretion was decreased, aldosterone excretion was suppressed while blood pressure and heart rate were minimally affected by epinephrine (1 μg/min). Inulin and para-aminohippurate clearances changed transiently and slightly during epinephrine infusions over 10 hr in normal subjects. In separate experiments, epinephrine lowered serum K, raised serum Na, raised plasma renin activity and, usually, lowered plasma aldosterone concentrations. There was an excellent correlation between epinephrine-induced changes in serum K and plasma aldosterone concentrations (r = +0.85, p < 0.001). Significant dose-response relationships were found between L-epinephrine infusion rates of 0.5–6.5 μg/min and observed serum K concentrations. We conclude that L-epinephrine infusions at rates probably well within the physiological range, induce hypokalemia (by increased cellular uptake of K) which lowers aldosterone secretion despite concomitant elevation of PRA and causes natriuresis for up to 24 hr.     

Steroidogenic cellular sites in the cat ovary: a histochemical study.

The distribution of lipids, NADH, NADPH diaphorase, glucose 6-phospate, the isocitrate dehydrogenases, Δ⁵-3β- and 17β-hydroxysteroid dehydrogenases, and acid phosphatase in immature, cycling, and pregnant cat ovaries has been histochemically studied. Corpora lutea were found only in pregnant cats. Acid phosphatase was present in the degenerating follicles and only in trace amounts in the corpora lutea and was absent in the interstitial gland cells, germinal epithelium, and the normal developing follicles. Lipids and the various enzymes studied were localized in the theca interna of preantral and antral follicles, interstitial gland cells, and in the corpora lutea. Germinal epithelium lacked lipids, diaphorases, and all the enzymes investigated. It is suggested that theca interna and the interstitial gland cells form principal sites of steroid synthesis in the ovaries of immature as well as cycling cats while corpora lutea form additional sites of steroidogenesis during pregnancy.     

Alterations in liver nucleic acids and nucleotides in arginine deficient rats

Dietary arginine deficiency is associated with retarded growth and depressed feed intake. Nucleic acid biosynthesis as indicated by the incorporation of [6-¹⁴C]-orotic acid and [³²p]-orthophosphate was significantly depressed in rats fed an arginine deficient diet. The activities of the pyrimidine enzymes, aspartate transcarbamylase (ATC) and dihydroorotate dehydrogenase (DHODH) were significantly increased in rats fed an arginine deficient diet. ATC and DHODH activities in rats fed the arginine deficient diet returned to control activities after 3 wk of feeding. Orotidine 5′ phosphate decarboxylase and orotate phosphoribosyl transferase activities were not affected by dietary arginine availability. In the rat fed an arginine deficient diet there was an increase in total liver pyrimidine nucleotides and a decrease in the total purine nucleotides. Significant alterations in the individual liver nucleotides were also observed. Incubation of various tissues obtained from rats fed an arginine deficient diet or a complete diet with glutamine (5mM) revealed that the liver is the major site of orotic acid synthesis. Orotic acid production in liver slices using glutamine as the nitrogen source was significantly greater in rats fed an arginine deficient diet compared to controls. The orotic aciduria occurring in rats fed an arginine deficient diet is associated with increased synthesis and decreased utilization of pyrimidines.