Acute abdominal pain in a man with Cushing syndrome.

Arterial thrombosis or emboli have rarely been reported in Cushing syndrome (CS). Here we describe the first case of mesenteric ischaemia secondary to ventricular emboli in a patient with CS. Laboratory evaluation showed increased fibrinogen and factor VIII. Previous studies showed that venous thromboembolism (VTE) increases in CS. This case for the first time described arterial system thrombosis and emboli in a patient with adrenocorticotropin (ACTH)-dependent CS.

Massive pericardial effusion and rhabdomyolysis secondary to untreated severe hypothyroidism: the first report.

Hypothyroidism is an endocrine disease with various clinical manifestations. It is a rare cause for rhabdomyolysis and massive pericardial effusion. We describe a case of severe hypothyroidism secondary to autoimmune hashimoto thyroiditis with massive pericardial effusion and rhabdomyolysis. Improvement of mentioned complications after hypothyroidism treatment and rule out of other possible causes are supportive clues that hypothyroidism is the main cause of patient's rare presentation. With the best of our knowledge, it is the first report of rhabdomyolysis and massive pericardial effusion coincidence in a patient of adult population with primary uncontrolled hypothyroidism for years.

Irradiation-induced expression of hyaluronan (HA) synthase 2 and hyaluronidase 2 genes in rat lung tissue accompanies active turnover of HA and induction of types I and III collagen gene expression.

Hyaluronan (HA) is a linear glycosaminoglycan that accumulates in the interstitium of injured lung and inhibits gas exchange between air and blood. In the present study we investigated the molecular mechanisms behind the local turnover of HA during the early phase of irradiation-evoked lung fibrosis in rats. Irradiation with a single dose of 30 Gy to the lower part of the right lung of rats induced an accumulation of HA in bronchoalveolar lavage fluid 6 wk after irradiation, followed by return to almost normal levels at 10 wk after irradiation. This was parallelled with a transient downregulation of HA receptors on alveolar macrophages (AMs); 4 and 6 wk after irradiation the binding of [(3)H]HA to AMs was decreased to about 50% of that of AMs from nonirradiated control rats, returning to almost normal level at 10 wk after irradiation. Analysis of the expression of rat HA synthase (HAS) isoforms (rHAS1, rHAS2, and rHAS3) and rat hyaluronidases (rHYAL1 and rHYAL2) by Northern blotting revealed an upregulation of rHAS2 messenger RNA at 4, 6, and 10 wk after irradiation, but a progressive decrease in the constitutive expression of rHYAL2 at 6 and 10 wk after irradiation; rHAS1 was undetectable, whereas rHAS3 and rHYAL1 were faintly detectable. Although transforming growth factor-beta1 stimulated HA production by normal lung fibroblasts, it inhibited HYAL activity in lysosomes and HYAL activity released into the culture media. Another interesting observation was that HA fragments, which likely result from the action of HYAL, induced expression of types I and III collagen genes. Our results indicate that rHAS2 and rHYAL2 are involved in the turnover of HA during the early phase of lung injury and that rHAS2 and rHYAL2 as well as HA fragments may play important roles in the pathogenesis of lung fibrosis.

Immunocytochemical localization of luteinizing hormone and follicle-stimulating hormone in the equine pituitary.

Gonadotropin-specific primary antisera and gold-conjugated secondary antibodies were used to immunocytochemically localize gonadotropins in the anterior pituitary of intact pony mares. Electron microscopy was then used to characterize the ultrastructure and immunoreactive staining characteristics of equine gonadotropes. Cells containing LH were morphologically indistinguishable from those containing FSH. Gonadotropes were relatively large and commonly had eccentric nuclei. The rough endoplasmic reticulum was well developed and dilated. Secretory granules were present in two morphologically distinct forms. Large polymorphic granules were generally located in perinuclear cytoplasmic areas, whereas small and uniformly shaped granules were in the peripheral cytoplasm, close to the cell membrane. Double-labeling revealed cells with granules that stained for both LH and FSH as well as cells that stained for either LH or FSH. Gonadotropes constituted 15 to 32% of all pituitary cells in the anterior pituitaries from the three mares included in this study. Cells that stained for only LH constituted 2 to 16% of all pituitary cells, cells that stained for only FSH ranged from 1 to 4.5%, and cells staining for both hormones constituted 6.2 to 24% of the pituitary cells. These results indicate that there are in fact three distinct subclasses of gonadotropes in the equine anterior pituitary based on immunocytochemical staining, which is similar to the situation described for several other mammalian species.

Immunocytochemical localization of prolactin and growth hormone in the equine pituitary.

The ultrastructural and immunoreactive staining characteristics of cells containing prolactin (lactotropes) and growth hormone (GH; somatotropes) in the anterior pituitaries of gonadally intact pony mares were studied at the electron microscopic level. Lactotropes included two morphological subsets: Type I cells were larger and contained large, dense, polymorphic granules that were scattered throughout the cytoplasm; Type II cells were smaller and contained small, dense, polymorphic granules that were predominantly found in peripheral areas of the cytoplasm. Lactotropes constituted 5 to 16% of the total number of cells in the pituitary. Somatotropes were medium-sized cells containing uniform, large, dense secretory granules. The somatotropes contained the largest secretory granules in the pituitary and represented 11 to 26% of the total number of cells. Type I lactotropes and somatotropes were readily distinguishable without immunocytochemical staining. Double-labeling of pituitary sections allowed for characterization of cells that contained both hormones (mammosomatotropes). These cells were morphologically indistinguishable from Type I lactotropes and constituted 6.5 to 16.5% of the total number of cells. Results from this study demonstrated that there are two cell populations that contain only prolactin (Type I and II lactotropes) and one cell population that contains only GH (somatotropes) in the equine pituitary, and an additional subset of cells that contains GH and prolactin in the same secretory granules.

Hyaluronan oligosaccharides induce tube formation of a brain endothelial cell line in vitro.

In remodeling tissues the formation of new blood vessels is an essential process which is regulated by different factors. During such processes an increase in hyaluronan synthesis and turnover is often seen and recent observations have suggested that hyaluronan can both promote and inhibit neovascularization depending on its molecular mass. In this work we show that a brain capillary endothelial cell line forms tubes in a collagen gel after stimulation by hyaluronan oligosaccharides. Ultrastructural examination of the tubes by transmission electron microscopy revealed that the cord-like outgrowths consisted of 2-10 tightly packed cells containing a continuous lumen. The tube formation in response to hyaluronan oligosaccharide was not mediated by activation of receptors for fibroblast growth factor. The endothelial cell line, which does not synthesize hyaluronan, exhibited specific hyaluronan-binding sites, with about 3000 hyaluronan molecules (M(r) 3.85 x 10(6)) bound per cell at saturation and Kd was 0.05 x 10(-9) M. Furthermore, the cell line was stained with mAb IVd4 that recognizes a novel class of hyaluronan-binding proteins and mAb IM7 which recognizes CD44 molecules.

Growth hormone and prolactin concentrations in plasma of horses: sex differences and the effects of acute exercise and administration of growth hormone-releasing hormone.

Three experiments were conducted to determine 1) the relationship between prolactin and growth hormone (GH) secretion in mares and the response to GH-releasing hormone (GHRH), 2) whether plasma GH and prolactin concentrations differed among mares, stallions, and geldings, and 3) whether sexual differences existed after administration of GHRH and acute exercise. In Exp. 1, 10-min blood samples were collected from 12 mares for 8 h, and GHRH (0, 45, 90, or 180 micrograms) was administered at 6 h. In Exp. 2, 15-min blood samples were collected for 4 h from 10 mares, stallions, and geldings. In Exp. 3, eight horses of each sexual status were administered GHRH at 0900; later that day, each horse was exercised for 5 min. Blood samples were collected every 10 min around each event. In Exp. 1, prolactin concentrations decreased (P < .01) over the 8-h period, and there was an average of 2.9 +/- .5 episodes of increased secretion during that time; there was no correlation between these episodes and those in GH secretion. Prolactin concentrations were not affected (P > .1) by GHRH. In Exp. 2, average concentrations of GH were 2.4, 8.6, and 8.5 ng/mL for mares, stallions, and geldings, respectively; males differed from females (P < .05). Stallions and geldings had more (P < .05) peaks in GH concentrations and greater (P < .05) amplitude of peaks than mares. In contrast, prolactin concentrations were greater (P < .02) in mares and stallions than in geldings. In Exp. 3, GH response to GHRH was greater (P < .03) in stallions than in mares or geldings.(ABSTRACT TRUNCATED AT 250 WORDS)

Growth hormone in mares and stallions: pulsatile secretion, response to growth hormone-releasing hormone, and effects of exercise, sexual stimulation, and pharmacological agents.

Short-term patterns of growth hormone (GH) secretion and factors affecting it were studied in mares and stallions. In Exp. 1, hourly blood samples were collected from three mares and three stallions in summer and winter. Although GH concentrations varied in a pulsatile manner in all horses, there was no effect of sex or season (P greater than .1) on plasma GH concentrations and no indication of a diurnal pattern of GH secretion. In Exp. 2, 10-min blood samples were drawn for 8 h from 12 mares; after 6 h, porcine GH-releasing hormone (GHRH) was administered i.v. at 0, 45, 90, or 180 micrograms/mare (three mares per dose). Pulsatile secretion of GH occurred in all mares and averaged 2.4 +/- .3 peaks/6 h; amplitudes were variable and ranged from 2.6 to 74.4 ng/mL. Eight of nine mares responded within 20 min to GHRH injection, but there was no difference (P greater than .1) among the three doses tested. In Exp. 3, plasma GH concentrations in stallions increased (P less than .05) 8- to 10-fold after 5 min of acute physical exercise or exposure to an estrual mare. Restraint via a twitch (5 min) and epinephrine administration (3 mg i.v.) also increased (P less than .05) plasma GH concentrations by approximately fourfold. In Exp. 4 and 5, administration of either .4, 2, or 10 mg of thyrotropin-releasing hormone (TRH) or 100 or 500 mg of sulpiride (a dopamine receptor antagonist) increased (P less than .01) plasma prolactin concentrations but had no effect (P greater than .1) on GH concentrations during the same period of time.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma concentrations of cortisol, prolactin, luteinizing hormone, and follicle-stimulating hormone in stallions after physical exercise and injection of secretagogue before and after sulpiride treatment in winter.

Ten lighthorse stallions were used to determine 1) whether prolactin (PRL) and cortisol responses previously observed after acute exercise in summer would occur in winter when PRL secretion is normally low, 2) whether subsequent treatment with a dopamine receptor antagonist, sulpiride, for 14 d would increase PRL secretion and response to thyrotropin-releasing hormone (TRH) and exercise, and 3) whether secretion of LH, FSH, and cortisol would be affected by sulpiride treatment. On January 11, blood samples were drawn from all stallions before and after a 5-min period of strenuous running. On January 12, blood samples were drawn before and after an i.v. injection of GnRH plus TRH. From January 13 through 26, five stallions were injected s.c. daily with 500 mg of sulpiride; the remaining five stallions received vehicle. The exercise and secretagogue regimens were repeated on January 27 and 28, respectively. Before sulpiride injection, concentrations of both cortisol and PRL increased (P less than .05) 40 to 80% in response to exercise; concentrations of LH and FSH also increased (P less than .05) approximately 5 to 10%. Sulpiride treatment resulted in (P less than .05) a six- to eightfold increase in daily PRL secretion. The PRL response to TRH increased (P less than .05) fourfold in stallions treated with sulpiride but was unchanged in control stallions. Sulpiride treatment did not affect (P greater than .05) the LH or FSH response to exogenous GnRH.(ABSTRACT TRUNCATED AT 250 WORDS)

Function of ovine corpora lutea after administration of luteinizing hormone-releasing hormone.

Ewes were treated with an agonistic analog of luteinizing hormone-releasing hormone (LH-RH) during the luteal phase (d 10) of the estrous cycle. Function of natural and hormonally-induced corpora lutea (CL) was evaluated by measurements of progesterone in sera or luteal tissue. Synthesis and secretion of progesterone by natural CL were not chronically altered by LH-RH. Likewise, there was no in vitro effect of LH-RH on luteal function. When natural CL were surgically removed, newly formed CL functioned at a defective level. Hysterectomy shortly after ovulation did not significantly influence such luteal activity. Induction of ovulation by LH-RH during the follicular phase (d 16) in uterus-intact ewes was followed by normal profiles of luteal secretion of progesterone; serum concentrations of progesterone in animals that were hysterectomized increased in association with development of the CL, but then plateaued at a subnormal level. There were no differences in patterns of secretion of luteinizing hormone in response to LH-RH due to stage of the estrous cycle. Follicles stimulated to ovulate during the luteal phase contained low numbers of steroidogenically-deficient granulosal-lutein cells. These results indicate that: ovine CL are not sensitive to exogenous LH-RH; luteal dysfunction is a consequence of ovulation during the luteal phase, and the etiology of this abnormality appears to be linked with the developmental status of the ovulatory follicle; and CL that are formed from ovulation of a matured follicle begin to develop normally, but then function at a defective rate in the absence of the uterus.

Multiplicity of leucine transport systems in Escherichia coli K-12.

The major component of leucine uptake in Escherichia coli K-12 is a common system for l-leucine, l-isoleucine, and l-valine (LIV-I) with a Michaelis constant (K(m)) value of 0.2 muM (LIV-I system). The LIV-binding protein appears to be associated with this system. It now appears that the LIV-I transport system and LIV-binding protein also serve for the entry of l-alanine, l-threonine, and possibly l-serine. A minor component of l-leucine entry occurs by a leucine-specific system (L-system) for which a specific leucine-binding protein has been isolated. A mutant has been obtained that shows increased levels of the LIV-I transport activity and increased levels of both of the binding proteins. Another mutant has been isolated that shows only a major increase in the levels of the leucine-specific transport system and the leucine-specific binding protein. A third binding protein that binds all three branched-chain amino acids but binds isoleucine preferentially has been identified. The relationship of the binding proteins to each other and to transport activity is discussed. A second general transport system (LIV-II system) with a K(m) value of 2 muM and a relatively low V(max) can be observed in E. coli. The LIV-II system is not sensitive to osmotic shock treatment nor to growth of cells in the presence of leucine. This high K(m) system, which is specific for the branched-chain amino acids, can be observed in membrane vesicle preparations.