Concise Publication
Citation Information: J Clin Invest. 1972;51(11):2981-2983. https://doi.org/10.1172/JCI107124.
Abstract
Bone marrow colony formation in soft gel culture may be stimulated by substances elaborated by human peripheral blood leukocytes. In order to determine the cell type responsible for colony stimulation, peripheral leukocytes were separated by Ficoll-Hypaque gradients and differential glass adhesion. Morphologic, histochemical, and functional criteria were applied to determine the purity of the monocyte, lymphocyte, and neutrophil fractions.
Authors
David W. Golde, Martin J. Cline
Citation Information: J Clin Invest. 1972;51(11):2984-2987. https://doi.org/10.1172/JCI107125.
Abstract
Oxygen equilibrium was determined on hemoglobin of individuals both heterozygous and homozygous for hemoglobin E. The whole blood oxyhemoglobin dissociation curve of AE blood was identical to that of normal AA blood. E hemoglobin, isolated by diethylaminoethyl Sephadex and carboxymethyl cellulose column chromatography, had oxygen affinity, heme-heme interaction, and Bohr effect identical to those of hemoglobin A prepared from the same column. Furthermore, the two hemoglobins had equal reactivity with 2,3-diphosphoglycerate. Phosphate-free hemolysates of blood from E and A homozygotes also had identical oxygen saturation curves. These results do not confirm earlier reports that hemoglobin E has an abnormally low oxygen affinity.
Authors
H. Franklin Bunn, W. Delano Meriwether, Stanley P. Balcerzak, Donald L. Rucknagel
Citation Information: J Clin Invest. 1972;51(9):2493-2497. https://doi.org/10.1172/JCI107063.
Abstract
6-n-propylthiouracil (PTU) administered to male Sprague-Dawley rats maintained on 2 and 5 μg L-thyroxine (T4)/100 g body weight resulted in a marked reduction in the rate of conversion of L-thyroxine to L-triiodothyronine (T3). These effects could not be ascribed to induced hypothyroidism since the group maintained on 5 μg T4/day had normal levels of liver mitochondrial alpha glycerophosphate dehydrogenase. In confirmation of previous studies, PTU also reduced the fractional rate of deiodination of T3. These observations provide a possible explanation of the many published observations indicating that PTU antagonizes the tissue effects of T4 but not of T3. The data suggest that monodeiodination of T4 but not of T3 is essential before hormonal effects can be manifested at the cellular level.
Authors
Jack H. Oppenheimer, Harold L. Schwartz, Martin I. Surks
Citation Information: J Clin Invest. 1972;51(9):2498-2501. https://doi.org/10.1172/JCI107064.
Abstract
Thyroidectomized and euthyroid rats were injected with three doses of triiodothyronine (T3) or of the diluent over a 6 day period, and liver homogenates were assayed for basal, epinephrine-stimulated, and NaF-stimulated adenyl cyclase activity. Based on NaF-stimulated levels, total adenyl cyclase activity, expressed per milligram of liver protein, was increased after thyroidectomy. Administration of T3 to either hypothyroid or euthyroid rats, however, had no effect on the NaF-stimulated levels. Basal and epinephrine-stimulated enzyme activities were the same in hypothyroid, euthyroid, and hyperthyroid (euthyroid + T3) liver homogenates. In contrast, injections of T3 in hypothyroid rats increased the activities of basal and epinephrine-stimulated adenyl cyclase. In view of the findings in euthyroid and hyperthyroid liver, it is possible that this effect is transient. In general, no correlation was found between the effects of thyroid hormone on respiration and on adenyl cyclase activity of the rat liver. These results imply that the hepatic thermogenic response to thyroid hormone is not mediated by stimulation of adenyl cyclase activity with the possible exception of the early effects of T3 in the athyroid rat.
Authors
Judith K. Jones, Faramarz Ismail-Beigi, Isidore S. Edelman
Citation Information: J Clin Invest. 1972;51(9):2502-2504. https://doi.org/10.1172/JCI107065.
Abstract
Isolated renal tubules from vitamin D-deficient chicks catalyse the in vitro conversion of 25-hydroxycholecalciferol to 1,25-dihydroxycholecalciferol. This conversion is stimulated by 5 × 10-10 M bovine parathyroid hormone, or by 10-6 M cyclic AMP. It is inhibited by 10-9 M porcine calcitonin. It is concluded that these hormonal controls of the synthesis of the renal hormone 1,25-dihydroxycholecalciferol are of particular physiological significance in coordinating the activities of the various organs involved in extracellular calcium homeostasis.
Authors
Howard Rasmussen, Mitzi Wong, Daniel Bikle, David B. P. Goodman
Citation Information: J Clin Invest. 1972;51(8):2211-2213. https://doi.org/10.1172/JCI107029.
Abstract
Chow-fed and tocopherol-deficient mice were given aminotriazole (AT), exposed to 100% O2 at 60 pounds per square inch absolute for 1 hr (OHP), and red blood cells were assayed for catalase activity and lipid peroxide levels. A decrease of catalase activity (CA) in the presence of AT can be taken as evidence of excess formation or accumulation of H2O2. No differences of CA were observed among chow-fed mice, with or without AT and/or OHP. Tocopherol-deficient mice with AT had lower CA (0.174±0.040) than chow-fed mice with AT (0.225±0.028) P < 0.01. Tocopherol-deficient mice with AT exposed to OHP had even lower CA, 0.137±0.024, P < 0.01.
Authors
William P. Johnson, Devenia Jefferson, Charles E. Mengel
Citation Information: J Clin Invest. 1972;51(7):1910-1914. https://doi.org/10.1172/JCI106994.
Abstract
Rabbit polymorphonuclear leukocytes ingesting paraffin oil particles stabilized with albumin, converted more lysolecithin-32P (added to the medium as an albumin complex) to cellular lecithin than did control cells.
Authors
P. Elsbach, P. Patriarca, P. Pettis, T. P. Stossel, R. J. Mason, M. Vaughan
Citation Information: J Clin Invest. 1972;51(7):1915-1918. https://doi.org/10.1172/JCI106995.
Abstract
The uptake of free and bound 57CoB12, principally to transcobalamin II (TC II), was studied in isolated, perfused liver and kidney of the dog. (1) There was good uptake of canine TC II-B12 by both organs. (2) In the liver TC II enhanced uptake over that of free B-12. (3) Renal uptake of free B-12 was greater than that of TC II-B12. Free B-12 was neither lost in the urine nor returned to the circulation. (4) On a per gram tissue basis, renal uptake of TC II-B12 was greater than hepatic. (5) There was renal release or production of TC II (6) Some TC II but more of a larger molecular size binder came from the liver. (7) Passing free B-12 through the kidney enhanced its uptake by the liver. (8) Passing free B-12 through the liver depressed its uptake by the kidney. (9) It is postulated that the distribution of B-12 can be modified by (a) different responses of tissue to TC II-B12, (b) synthesis of TC II by an organ, and (c) the effects of B-12 passing through one organ to another.
Authors
Mary E. Rappazzo, Charles A. Hall
Citation Information: J Clin Invest. 1972;51(7):1919-1922. https://doi.org/10.1172/JCI106996.
Abstract
The activity of dihydrotachysterol and cholecalciferol was determined in nephrectomized or sham-operated vitamin D-depleted rats using in vitro transport of calcium and phosphate by everted intestinal preparations as the index of physiologic response. The activity of dihydrotachysterol was not reduced by absence of the kidneys whereas that of cholecalciferol was markedly inhibited so that at least a 10-fold greater dose of the latter was necessary to produce an equivalent effect in the nephrectomized rat as in the control. Dihydrotachysterol is therefore equipotent with cholecalciferol in the anephric rat although much less active in the intact animal.
Authors
Harold E. Harrison, Helen C. Harrison
Citation Information: J Clin Invest. 1972;51(7):1923-1926. https://doi.org/10.1172/JCI106997.
Abstract
Cholesteryl ester storage disease has been shown to involve severe deficiency of acid cholesteryl ester hydrolase and triglyceride lipase activity in liver, spleen, and lymph node. The cholesteryl ester hydrolase was also deficient in aorta. Tissue storage of both cholesteryl esters and triglycerides is generalized. Both the lipid and enzymatic changes are very similar to those in Wolman's disease.
Authors
Howard R. Sloan, Donald S. Fredrickson
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