Ovine corticotropin-releasing factor (oCRF) stimulates increased plasma immunoreactive adrenocorticotropin (IR-ACTH) and IR-cortisol at threshold, half-maximal, and maximal doses of 0.01-0.03, 0.
View Article and Find Full Text PDFWhen only 1 hindlimb of the adult mouse was immobilized for 13 h, the immobilization-induced failure of insulin to stimulate 2-deoxyglucose uptake was observed in the immobilized soleus muscle. 2-deoxyglucose uptake was unchanged in the contralateral, nonimmobilized muscle. In the rat, protein synthesis rates decreased in the one immobilized limb as compared to rates measured in the contralateral nonimmobilized limb of the same animal.
View Article and Find Full Text PDFA cross-sectional medical examination of a copper smelter work force included determination of blood lead (Pb-B), zinc protoporphyrin (ZPP), blood cadmium (Cd-B), urinary cadmium (Cd-U), and urinary arsenic (As-U), since it was known that such metal impurities were present in the copper concentrate. A total of 776 copper smelter employees (680 active and 96 retirees and ex-employees) were examined. Another 144 men, never employed in the smelter, but who had worked in copper mines (and sometimes in gold mines) were also examined.
View Article and Find Full Text PDFJ Appl Physiol Respir Environ Exerc Physiol
February 1984
The purposes of this study were to determine whether the defects in glucose metabolism in muscles of immobilized limbs of mice were related to alterations in insulin binding, insulin responsiveness, glucose supply, and insulin activation of glycogen synthase. These were tested by in vitro methodology. A significant lessening in the insulin-induced maximal response of 2-deoxyglucose uptake into the mouse soleus muscle occurred between the 3rd and 8th h of limb immobilization, suggesting a decreased insulin responsiveness.
View Article and Find Full Text PDFThis RIA for corticotropin (ACTH) involves use of a commercially available antiserum and permits measurement of immunoreactive ACTH in unextracted plasma. The assay takes 2.5 days, detects as little as 5 pg/mL of plasma, and is specific: structurally and (or) biosynthetically related peptides do not cross react.
View Article and Find Full Text PDFProg Clin Biol Res
May 1984
A high risk of death from liver HSA has been documented from past exposures to VC. Similar to other carcinogens, the risk of VC-induced liver HSA appears to increase as the second or third power of time from onset of exposure. It is possible to project future mortality using this power relationship, estimates of VC exposure, and observed mortality to 1980.
View Article and Find Full Text PDFOverall, the results of the analysis of 12 studies of VC production and polymerization workers demonstrate an enormously elevated risk of liver malignancies, the possibility of a twofold increased risk of brain and central nervous system tumors and perhaps, also, of malignancies of the lymphatic and hematopoietic system. However, the role of other agents cannot be excluded in the etiology of nonhepatic malignancies. Bronchogenic carcinoma does not appear to be increased from exposures to VC monomer, although a relationship to PVC dust was suggested in one study.
View Article and Find Full Text PDFThe plasma distribution, disappearance half-time, MCR, and degradation of corticotropin-releasing factor (CRF) were studied in normal men who received a pulse injection of synthetic ovine CRF (oCRF). Graded iv doses of oCRF produced a linear increase in plasma immunoreactive oCRF (IR-oCRF). The calculated total plasma content of IR-oCRF 2 min after injection represented 41.
View Article and Find Full Text PDFEnviron Health Perspect
November 1983
Immunogenetic study of alleged first-degree relatives was undertaken among 258 prospective United States immigrants from Haiti. Methods involved serotyping red cells for ABO, Rh, and MN antigens and typing leukocytes for HLA, A, B, and C locus antigens. Kinship was definitely excluded in a relatively low 4.
View Article and Find Full Text PDFUrinary mutagen levels were measured over an 8-week period in a group of 13 smokers. Individual urinary mutagen levels were observed to be relatively constant and while there was a general correlation between mutagen excretion levels and cigarette consumption, individuals' excretion levels could not be predicted on the basis of either the numbers of cigarettes smoked or the tar content of the cigarettes.
View Article and Find Full Text PDFImmunoreactive plasma levels of the proopiolipomelanocortin-derived peptides, ACTH, beta-endorphin-lipotropin, and gamma 3MSH, were measured in patients with primary hyperaldosteronism, idiopathic hyperaldosteronism with bilateral adrenal hyperplasia, and dexamethasone-suppressible hyperaldosteronism. Plasma peptide concentrations in patient groups were not different from those in normal controls. Removal of aldosterone-producing adenomas in three patients and of an aldosterone-producing adrenocortical carcinoma in one patient did not affect plasma peptide concentrations.
View Article and Find Full Text PDFThe inhibitory effects of sera from starved, hypophysectomized, and alloxan-diabetic rats on basal and somatomedin-stimulated sulfate incorporation into cartilage from hypophysectomized rats were compared. The somatomedin inhibitory activity in serum from diabetic rats behaved like that in serum from starved rats on heating at 60 C. Both were labile in the native sera (pH 8.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
November 1982
It has been previously established that hypophysectomy leads to renal atrophy in rats and that a crude pituitary-derived fraction is effective in restoring kidney weight to the level expected for intact animals of the same body weight. This paper reports that considerable purification of the crude renotropic fraction from ovine pituitaries has been achieved and that the purified fraction is capable of restoring kidney weights of hypophysectomized castrated rats to normal values. For example, after five daily subcutaneous injections (135 micrograms/day) there were significant increases in dry kidney weight and total renal protein and DNA.
View Article and Find Full Text PDF1. We examined the effect of ischaemic pain and sustained isometric muscle contraction on plasma immunoreactive gamma-lipotropin (gamma LPH), beta-endorphin/beta-lipotropin (beta END/beta LPH) and corticotropin (ACTH), which are all synthesized from a common precursor (pro-opiocortin), and plasma cortisol in 10 normal subjects. 2.
View Article and Find Full Text PDFBeta-Lipotropin was purified from human pituitary glands to a purity of greater than 90%. The amino acid compositions of beta-lipotropin and its three cyanogen bromide cleavage peptide fragments were in agreement with the structure proposed by Li and Chung [Li, C.H.
View Article and Find Full Text PDFEquine Cushing's disease is caused by hypersecretion of ACTH by hyperplasia or adenomas of pars intermedia (PI) cells, in contrast to human Cushing's disease, which is caused by hyperplasia or adenomas of pars distalis (PD) ACTH-secreting cells. We assayed both bioactive and immunoreactive (IR) ACTH in two normal equine pituitary glands and in the PD, PI, and pars nervosa of four such glands, as well as in the PI adenomas of five horses with Cushing's disease. In normal horse pituitaries, as in those of other species, most of the bioactive and IR-ACTH was found in PD, much less in PI, and only traces in pars nervosa.
View Article and Find Full Text PDFThe side entry specimen stage described in this paper is a development of a specimen stage for use at room temperature in the JEOL JEM 100 and 200 series transmission electron microscopes. The earlier specimen stage was designed to ensure that the extraneous instrumental contribution to thin specimen X-ray spectra is both small and quantifiable. As well as having a low X-ray background the new stage will also maintain the specimen at temperatures sufficiently low (down to 100 K) to minimize the loss of organic material due to electron irradiation.
View Article and Find Full Text PDFThe Sorvall MT2B ultramicrotome and cryoattachment were modified to extent the duration of cutting and to overcome problems in tissue preparation. Microtome and cryochamber were encased and surrounded by an atmosphere of dry nitrogen gas at room temperature. A specially designed cold block sited within the box close to the microtome enabled tissues to be trimmed at low temperatures in the dry environment.
View Article and Find Full Text PDFJ Clin Endocrinol Metab
March 1982
Stimulation of aldosterone and corticosterone production by pituitary peptides structurally or biosynthetically related to ACTH was investigated in suspensions of isolated rat adrenal glomerulosa and fasciculata cells, respectively. Three different preparations of highly purified ovine (Li) or human (Chrétien and Orth) beta-lipotropin (beta LPH) were tested. In contrast to synthetic ACTH-(1-24), which stimulated aldosterone secretion at concentrations of 10(-12)-10(-11) M, beta LPH concentrations of 10(-8)-10(-6) M were required for significant stimulation.
View Article and Find Full Text PDFUsing RIAs for six regions within proopiolipomelanocortin (proOLMC), gel filtration, and electrophoresis, we studied pituitary peptides in a normal horse and one with Cushing's disease caused by a pars intermedia adenoma. Almost all immunoreactive (IR) ACTH (78%) was 4,500 mol wt (4.5K) ACTH in normal pars distalis, but it was almost 100% corticotropin-like intermediate lobe peptide (CLIP) in normal pars intermedia.
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