Stimulation by serum of aldosterone production from rat adrenal glomerulosa cells in vitro: relationships to K+, serotonin and angiotensin II

1981 ◽  
Vol 97 (2) ◽  
pp. 231-242 ◽  
Author(s):  
F. A. O. Mendelsohn ◽  
Christine D. Kachel
Keyword(s):  
Angiotensin Ii ◽  
Human Serum ◽  
Normal Subjects ◽  
Normal Human Serum ◽  
Rpmi Medium ◽  
High K ◽  
Aldosterone Production ◽  
Normal Human ◽  
Glomerulosa Cells

Abstract. Normal human serum markedly stimulated aldosterone production from rat adrenal glomerulosa cells incubated in Krebs Ringer bicarbonate medium (KRBGA). The effect was dose-related. In [K+] 3.6 mm KRBGA medium, serum stimulated aldosterone output to higher levels than those produced by maximal doses of serotonin (5 HT), angiotensin II (AII) or high [K+] (8.4 mm). Cells maximally stimulated by high [K+], 5 HT or AII in KRBGA medium were further stimulated by serum. The angiotensin analogue, [Sar1, Ala8]-AII abolished the effect of AII but not that of high [K+] or serum. Basal and ACTH-stimulated corticosterone outputs of rat fasciculata cells were not significantly affected by sera known to stimulate glomerulosa cells. Aldosterone stimulating activity of serum was dialysable and fully recovered in a serum ultrafiltrate. The serotonin blockers methysergide and metergoline abolished the aldosterone stimulating activity of serum but also depressed basal aldosterone output and methysergide reduced K+-stimulated output. Chymotrypsin digestion abolished the aldosterone stimulating activity of AII but not that of serotonin or serum. 5 HT concentration of sera was measured and found to be near the threshold for aldosterone stimulation. Sodium loading and depletion of 4 normal subjects did not consistently modify the aldosterone stimulating activity of their sera. In a supplemented medium (RPMI 1640), basal and K+-stimulated aldosterone outputs were higher than in KRBGA medium. Under these conditions serum stimulated aldosterone output in normal [K+] medium but only marginally in high [K+] medium. In RPMI medium, serum did not further stimulate cells maximally stimulated with serotonin. Serum appears to stimulate aldosterone production from glomerulsoa cells by two different mechanisms: One is probably due to a serotonin-like substance. A separate effect of serum, seen only in KRBGA medium, is to enhance aldosterone output of glomerulosa cells maximally stimulated by K+, 5 HT or AII.

Effects of Serum from Normal and Psoriatic Subjects on the Proliferation of Fibroblasts from Involved and Uninvolved Skin of Psoriatic Patients

1997 ◽  
Vol 1 (4) ◽  
pp. 196-202
Author(s):  
Gerald G. Krueger ◽  
Cynthia M. Jorgensen
Keyword(s):  
Human Serum ◽  
Bovine Serum ◽  
Fetal Bovine Serum ◽  
Normal Subjects ◽  
Normal Human Serum ◽  
Disease Expression ◽  
Uninvolved Skin ◽  
Normal Human ◽  
Fetal Bovine

Background: A framework hypothesis for the pathogenesis of psoriasis states that “there is an aberration throughout the skin of patients with psoriasis that is modified to disease expression by circulating factors.” Objective: A question to emerge from this hypothesis concerns whether fibroblasts could be more central to the aberration than other cells of the skin? This article focuses on the modulation of growth of fibroblasts from uninvolved and involved sites of patients with psoriasis as a function of the type of serum in which they are grown. Methods: Fibroblasts were generated from normal subjects and from involved and uninvolved sites of six untreated psoriatic subjects and their growth in vitro was assessed as a function of the type of serum (fetal bovine serum, normal human serum, and serum from psoriatic subjects) in which they are grown. Results: The data show (a) that fibroblasts from psoriatic subjects, especially from uninvolved sites, have an inherent capacity to proliferate at an enhanced rate relative to normal fibroblasts; (b) that this enhanced proliferation can be augmented by normal human serum and to a greater degree by serum from psoriatic subjects; (c) that ≈ 40% of the enhanced proliferation is secondary to the psoriasis serum phenotype; (d) that ≈ 30% of enhanced proliferation is secondary to the psoriasis fibroblast phenotype; and (e) that the magnitude of these features are independent of the severity of psoriasis, as assessed at the time of donation of biopsies for generation of test fibroblasts or of blood for serum. Conclusion: These data support the hypothesis that there is an aberration throughout the skin of patients with psoriasis (enhanced proliferation of fibroblasts in vitro, especially from uninvolved sites) that is modified by circulating factors (serum).

The Binding of Lithium Carmine to a2-Macroglobulin

1969 ◽  
Vol 24 (11) ◽  
pp. 1442-1447 ◽  
Author(s):  
J. J. Picard ◽  
J. F. Heremans
Keyword(s):  
Human Serum ◽  
Density Gradient ◽  
Protein Complex ◽  
Gel Filtration ◽  
Heavy Fraction ◽  
Normal Human Serum ◽  
Density Gradient Ultracentrifugation ◽  
Γ Globulins ◽  
Normal Human

The colloidal dye lithium carmine was added in vitro to normal human serum. Electrophoretic experiments showed that the dye was associated mainly with α2-globulins, small amounts with the albumin and only traces with the γ-globulins. The main complex was eluted with the macroglobulin peak obtained by gel filtration on Sephadex G-200 and sedimented in the heavy fraction on density gradient ultracentrifugation. The dye-protein complex could be precipitated with an antiserum specific for a2-macroglobulin. Gel filtration of a solution of pure a2-macroglobulin, to which lithium carmine was added, demonstrated that the dye was bound to this protein.

Inhibition of aldosterone release by hypoxia in vitro: interaction with carbon monoxide

1994 ◽  
Vol 76 (2) ◽  
pp. 689-693 ◽  
Author(s):  
H. Raff ◽  
B. Jankowski
Keyword(s):  
Carbon Monoxide ◽  
Angiotensin Ii ◽  
Zona Glomerulosa ◽  
Michaelis Constant ◽  
Aldosterone Synthase ◽  
Aldosterone Production ◽  
Glomerulosa Cells ◽  
In Vitro Interaction ◽  
Zona Glomerulosa Cells

We have demonstrated that the aldosteronogenic pathway of the zona glomerulosa is unusually sensitive to modest changes in PO2 (Michaelis constant for O2 approximately 95 Torr). The current study evaluated the interaction of CO (the classic ligand for P-450 enzymes) and the decreases in O2 on aldosteronogenesis in vitro. Bovine adrenocortical zona glomerulosa cells were incubated for 2 h and stimulated with either adenosine 3′,5′-cyclic monophosphate (cAMP) or angiotensin II. Ten and 20% CO led to significant decreases in cAMP- and angiotensin II-stimulated aldosteronogenesis. The combination of 20% CO and moderate decreases in PO2 (from approximately 140 to approximately 100 Torr) led to an interactive decrease in aldosterone production. The conversion of corticosterone to aldosterone catalyzed by aldosterone synthase, which is the site of O2 sensitivity, was not significantly inhibited by CO. We conclude that the aldosterone pathway is not exceptionally sensitive to CO compared with other steroidogenic pathways. This observation suggests that the unique O2-sensitive properties of the aldosterone pathway located primarily within aldosterone synthase may not reside in its CO binding site (i.e., heme).

scholarly journals The effect of normal human serum on the mouse trypanosome Trypanosoma musculi in vitro and in vivo

2018 ◽  
Vol 184 ◽  
pp. 115-120
Author(s):  
Xuan Zhang ◽  
Xiao-Kun Hong ◽  
Su-Jin Li ◽  
De-Hua Lai ◽  
Geoff Hide ◽  
...  
Keyword(s):  
Human Serum ◽  
Normal Human Serum ◽  
Normal Human

Identification of a trypanocidal factor againstTrypanosoma equiperdumin normal human serum

Parasitology ◽  
1989 ◽  
Vol 98 (3) ◽  
pp. 401-407 ◽  
Author(s):  
G. Verducci ◽  
S. Perito ◽  
R. Rossi ◽  
E. Mannarino ◽  
F. Bistoni ◽  
...  
Keyword(s):  
Human Serum ◽  
Gel Filtration ◽  
Density Lipoprotein ◽  
Natural Antibodies ◽  
Normal Human Serum ◽  
Mouse Serum ◽  
Trypanocidal Activity ◽  
Normal Human

SUMMARYNormal human serum (HS) contains trypanolytic activity and agglutinins toTrypanosoma equiperdum, while such activities are not found in sera from a range of animals susceptible to infection. HS given toT. equiperdum-infected mice caused a rapid decrease in the number of circulating trypanosomes and protection from lethal infection. Trypanolytic activity of human serum was found to be associated, after DEAE chromatography and Sephadex G-200 gel filtration, with the fraction containing 19S antibodies. Immunofluorescence assays confirmed a binding of human IgM and C1qcomplement component onto the surface ofT. equiperdum. Anti-T. equiperdumactivity of HS was specifically directed toT. equiperdumsurface components and not to some mouse serum components adsorbed on parasites during the growth in the host, because HS adsorbedin vivoin CD-1 mice retained full protective and agglutinating properties. Trypanocidal activity appears in human serum about the 7th month after birth and persists until late in life. On the contrary, human purified high-density lipoprotein had no significantin vitroorin vivotrypanocidal activity. In conclusion, strong natural anti-T. equiperdumactivity in human serum was mainly mediated by natural antibodies of the IgM class. The presence of natural IgM active againstT. equiperdumin HS could represent one of the natural mechanisms of resistance of refractory hosts against trypanosome infections. This phenomenon provides further evidence that host specificity of trypanosomes may be partly conditioned by the presence of natural antibodies.

scholarly journals Influence of the Length of the Lipooligosaccharide α Chain on Its Sialylation in Neisseria meningitidis

2002 ◽  
Vol 70 (1) ◽  
pp. 407-411 ◽  
Author(s):  
Chao-Ming Tsai ◽  
George Kao ◽  
Peixuan Zhu
Keyword(s):  
Neisseria Meningitidis ◽  
Human Serum ◽  
Steric Hindrance ◽  
Normal Human Serum ◽  
Normal Human ◽  
Α Chain

ABSTRACT The sialylation of lipooligosaccharide (LOS) in Neisseria meningitidis plays a role in the resistance of the organism to killing by normal human serum. The length of the α chain extending out from the heptose I [Hep (I)] moiety of LOS influenced sialylation of N. meningitidis LOS in vitro and in vivo. The α chain required a terminal Gal and a trisaccharide or longer oligosaccharide to serve as an acceptor for sialylation. The disaccharide lactose (Galβ1-4Glc) in the α chain of immunotype L8 LOS could not function as an acceptor for the sialyltransferase, probably due to steric hindrance imposed by the neighboring Hep (II) with phosphorylethanolamine and another group attached.

scholarly journals Comparison of the hemagglutination inhibition assay kit for erythropoietin (ESF) with the fetal mouse liver cell bioassay in vitro

Blood ◽  
1980 ◽  
Vol 55 (6) ◽  
pp. 955-959
Author(s):  
G de Klerk ◽  
RJ Vet ◽  
PC Rosengarten ◽  
R Goudsmit
Keyword(s):  
Human Serum ◽  
Liver Cell ◽  
Hemagglutination Inhibition ◽  
Mouse Liver ◽  
Normal Human Serum ◽  
Fetal Mouse ◽  
Mouse Liver Cell ◽  
Fetal Mouse Liver ◽  
Normal Human

The commercially available hemagglutination inhibition (HAI) assay kit for erythropoietin (ESF) was compared with the fetal mouse liver cell (FMLC) bioassay. No correlation was obtained ESF levels determined by both methods in a variety of pathologic sera. The HAI kit showed a great batch variability. Significant immunoreactivity was found in those fractions of a normal human serum and a human urinary ESF preparation that were not active in the FMLC bioassay. A very poor recovery of immunoreactivity was found when the international reference preparation for erythropoietin (second IRPE) was added to a normal human serum.

On the Complex Formation of Antithrombin III with Thrombin

1973 ◽  
Vol 30 (02) ◽  
pp. 280-283 ◽  
Author(s):  
B Binder
Keyword(s):  
Complex Formation ◽  
Human Serum ◽  
Blood Coagulation ◽  
Antithrombin Iii ◽  
Normal Human Serum ◽  
Molecular Weights ◽  
At Iii ◽  
Normal Human

SummaryBased on gelfiltration studies, the part of AT III which becomes bound to thrombin during the process of in vitro blood coagulation was calculated to be about 40% of total AT III. Complexes consisting of one AT III and one thrombin molecule could not be detected while fractions corresponding to molecular weights of about 190,000 Dalton show AT III as well as thrombin activities. The AT III - thrombin complex in normal human serum consists, therefore, of either 2 AT III and 2 thrombin molecules or of one AT III and 4 thrombin molecules.

scholarly journals Interaction of rheumatoid factor and Entamoeba histolytica

1989 ◽  
Vol 31 (4) ◽  
pp. 207-212
Author(s):  
P.G. Kremsner ◽  
W. Graninger
Keyword(s):  
Human Serum ◽  
Rheumatoid Factor ◽  
Entamoeba Histolytica ◽  
Normal Human Serum ◽  
Cytotoxicity Test ◽  
Marked Inhibition ◽  
Rabbit Igg ◽  
Lysis Rate ◽  
Normal Human

The amoebae's cytotoxicity test and the amoebae's lysis test were used to show possible interactions between rheumatoid factor (RF) and Entamoeba histolytica. Amoebae's cytotoxic activity (ACA) was inhibited by affinity chromatography purified antiamoebae rabbit IgG (RIgG). Enhanced inhibition could be demonstrated with RIgG plus RF. But the same marked inhibition of ACA could be seen when replacing RF by heat inactivated normal human serum as a control. About 50% amoebae's lysis occurred when amoebae were brought together with native normal human serum (NNHS) as a source of complement. Amoebae's lysis increased to 60% when incubated with NHS plus human antiamoebae antibodies. No further augmentation could be obtained by the addition of RF. Using RIgG instead of human antibodies the lysis rate did not increase. Incubation of amoebae, NNHS, RIgG and RF even reduced amoebae's lysis. RF neither has an effect on ACA nor on complement mediated AL in vitro.

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