Experimental Essential Hypertension in the Rat?

1981 ◽  
Vol 61 (s7) ◽  
pp. 355s-357s ◽  
Author(s):  
M. Nowaczynski ◽  
W. Nowaczynski ◽  
D. Mavoungou ◽  
G. Wilkins ◽  
K. Fung ◽  
...  
Keyword(s):  
Gel Filtration ◽  
Plasma Renin ◽  
Exchange Chromatography ◽  
Plasma Aldosterone ◽  
Male Rats ◽  
Heart Weight ◽  
Charge Heterogeneity ◽  
Plasma Electrolytes ◽  
Ultra Filtration ◽  
A Charge

1. A human urinary thermostable glycoprotein (ABG-TsU) believed to be a homologue of the plasma aldosterone-binding globulin (ABG) was isolated and purified by differential ultra-filtration, ion-exchange chromatography and gel filtration to electrophoretic homogeneity; it showed a charge heterogeneity in electrofocussing. 2. ABG-TsU was administered intraperitoneally to male rats in small daily doses (7 μg/day per rat). Sustained hypertension developed in 5–8 days. 3. The treated rats showed no changes in plasma electrolytes, aldosterone or plasma renin activity; however, a significant increase in heart weight was observed. 4. This hypertension appears to be adrenal dependent since it is prevented by bilateral adrenalectomy or administration of an aldosterone antagonist, but not by adrenalectomy when aldosterone is given concomitantly with ABG-TsU.

scholarly journals Effect of Combined Hormonal Replacement Therapy on the Aldosterone/Renin Ratio in Postmenopausal Women

2017 ◽  
Vol 102 (7) ◽  
pp. 2329-2334 ◽  
Author(s):  
Ashraf H. Ahmed ◽  
Richard D. Gordon ◽  
Gregory Ward ◽  
Martin Wolley ◽  
Brett C. McWhinney ◽  
...  
Keyword(s):  
Replacement Therapy ◽  
Postmenopausal Women ◽  
Plasma Renin ◽  
Plasma Aldosterone ◽  
Hormonal Replacement Therapy ◽  
Friedman Test ◽  
Hormonal Replacement ◽  
Contraceptive Agents ◽  
Plasma Electrolytes ◽  
Positive Results

Abstract Background: Plasma aldosterone/renin ratio (ARR) is the most popular screening test for primary aldosteronism (PA). Because both estrogen and progesterone (including in oral contraceptive agents) affect aldosterone and renin levels, we studied the effects of combined hormonal replacement therapy (HRT) on ARR; renin was measured as both direct renin concentration (DRC) and plasma renin activity (PRA). Methods: Fifteen normotensive, healthy postmenopausal women underwent measurement (seated, midmorning) of plasma aldosterone, DRC, PRA, electrolytes, and creatinine and urinary aldosterone, cortisol, electrolytes, and creatinine at baseline and after 2 weeks and 6 weeks of treatment with combined HRT (conjugated estrogens 0.625 mg and medroxyprogesterone 2.5 mg daily). Results: Combined HRT was associated with statistically significant increases in aldosterone [median (range): baseline, 150 (85 to 600); 2 weeks, 230 (129 to 790); 6 weeks, 434 (200 to 1200) pmol/L; P < 0.001 (Friedman test)] and PRA [2.3 (1.2 to 4.3), 3.8 (1.4 to 7.0), 5.1 (1.4 to 10.8) ng/mL/h, respectively; P < 0.001] but decreases in DRC [21 (10 to 31), 21 (10 to 39), and 14 (8.0 to 30) mU/L, respectively; P < 0.01], leading to increases in ARR calculated by DRC [7.8 (3.6 to 34.8), 11.4 (5.4 to 48.5), and 30.4 (10.5 to 90.2), respectively; P < 0.001]. The ARR calculated by DRC exceeded the cutoff value (70) in three patients after 6 weeks. There were no significant changes in ARR calculated by PRA [79 (26 to 184), 91 (23 to 166), and 88 (50 to 230), respectively; P = 0.282], plasma electrolytes and creatinine, or any urinary measurements. Conclusion: The combined oral HRT used in this study is capable of significantly increasing ARR with a risk of false-positive results during screening for PA but only if DRC (and not PRA) is used to calculate the ratio.

PURIFICATION OF "INHIBIN" FROM HUMAN OVARIAN FOLLICULAR FLUID

1979 ◽  
Vol 90 (1) ◽  
pp. 157-166 ◽  
Author(s):  
S. Chari ◽  
C. R. N. Hopkinson ◽  
E. Daume ◽  
G. Sturm
Keyword(s):  
Follicular Fluid ◽  
Polyacrylamide Gel Electrophoresis ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Exchange Chromatography ◽  
Male Rats ◽  
Acetone Powder ◽  
Gel Chromatography ◽  
Apparent Homogeneity ◽  
Ovarian Follicular Fluid

ABSTRACT Following the earlier demonstration of inhibin-like activity in human ovarian follicular fluid a method for its purification to apparent homogeneity is described. The fluid was converted to acetone powder and subjected sequentially to ammonium sulphate fractionation, gel chromatography on Sephadex G-200, continuous gradient ion-exchange chromatography on DEAE-cellulose, first with a pH gradient from 8.0 to 4.0 and then with a NaCl gradient to 1 m at pH 5.2. The active fraction from this step was subjected to gel filtration on Sephadex G-100 and finally passed through an Amicon Centriflo membrane CF-25 (cut off point: 25 000 m.w.). The ultrafiltrate was homogeneous by SDS-polyacrylamide gel electrophoresis, had a molecular weight of the order of 23 000 and was capable of suppressing serum gonadotrophin levels in the castrated male rats in as low a dose as 25 μg/rat.

Soybean seed pectinesterase

1998 ◽  
Vol 8 (4) ◽  
pp. 455-461 ◽  
Author(s):  
Oskar Markovič ◽  
Ralph L. Obendorf
Keyword(s):  
Methyl Esters ◽  
Simultaneous Detection ◽  
Gel Filtration ◽  
Soybean Seed ◽  
Exchange Chromatography ◽  
Water Soluble ◽  
Soluble Form ◽  
Ph Optimum ◽  
Ultrathin Layers ◽  
Ultra Filtration

AbstractMethanol accumulates in axis tissues of maturing soybean seeds, correlating with preharvest seed deterioration. Accumulation of methanol appears to be associated with the enzymic demethylation of pectin methyl esters by pectinesterase (PE; EC 3.1.1.11). To characterize PE in developing and maturing soybean (Glycine max (L.) Merrill) seeds, enzyme activity was assayed in axis and cotyledon tissues. Activity per g fresh weight was 20–25 times higher in axes than in cotyledons with highest activities between 45 and 60 days after flowering (DAF). Twenty to 33% of the total PE activity was in the ‘soluble’ form (extracted with water, 0.5 M sucrose, 1 M sucrose and water). Soluble and cell-wall-bound PE (subsequently extracted with 1 M NaCI) were purified and characterized from axes of seeds at 45–60 DAF. Purification of PE was achieved through concentration of extracts by ultra-filtration, precipitation with ammonium sulfate (30–80% saturation), dialysis, gel filtration on Sephadex G-75 columns, and ion exchange chromatography on CM Sepharose CL-6B. Further purification of both soluble and bound PE was by isoelectric focusing (IEF) on ultrathin layers of polyacrylamide gel with simultaneous detection of protein and PE activity. It was possible to follow seven bands exhibiting PE activity with pl values between 6.0 and 9.5 in 1 M NaCI-extracts of total homogenates. Differences in the IEF patterns of bound and soluble PE were observed. Whereas the bound enzyme exhibited more basic PE bands (pl 8–9.5), the soluble enzyme had more active bands at pl 6.5, 7.0 and 7.5. The Mr was close to 33 000 and the pH optimum was 7.8 for both soluble and bound PE.

Chronic low-sodium diet in rats: responses to severe heat exposure

1985 ◽  
Vol 58 (1) ◽  
pp. 152-156 ◽  
Author(s):  
R. P. Francesconi ◽  
R. W. Hubbard
Keyword(s):  
Heat Stress ◽  
Thermal Sensitivity ◽  
Heat Exposure ◽  
Plasma Renin ◽  
Plasma Aldosterone ◽  
Male Rats ◽  
Control Group ◽  
Low Sodium Diet ◽  
Low Sodium ◽  
Severe Heat Stress

To determine the effects of sodium (Na+) deficiency on the responses to severe heat stress (35.5 degrees C), immature (mean wt 150.4 g) male rats (n = 21) were fed a low-Na+ diet for 71 days. Rates of weight gain and food consumption were significantly (P less than 0.001) reduced in the low-Na+ group, whereas water consumption was unaffected. Prior to heat exposure circulating Na+ levels were unaffected by dietary Na+ restriction, but both circulating potassium (K+) and hematocrit levels were significantly (P less than 0.001) increased. After 24-h exposure to severe heat stress, circulating Na+ levels did manifest a significant (P less than 0.001) decrement in the low-Na+ group. K+ levels increased significantly (P less than 0.01) in the control group after 6 h of heat exposure but remained depressed in comparison with the low-Na+ group after 48 and 72 h. Although plasma renin activity (PRA) was not increased by chronic consumption of the low-Na+ diet or by severe heat exposure in the control group, severe heat stress in the low-Na+ group did elicit significant (P less than 0.005) increments in PRA after 24 h of exposure. Alternatively, plasma aldosterone levels were significantly (P less than 0.001) elevated by both the low-Na+ diet and heat stress. We concluded from these studies that chronic consumption of the low-Na+ diet had severe effects on hematologic, endocrinological, and thermoregulatory variables as well as thermal sensitivity to prolonged and sedentary exposure to severe heat stress.

Electron Microscopic Analysis of Myonecrosis Induced by a Pure Component Isolated From Rattlesnake Venom

1976 ◽  
Vol 34 ◽  
pp. 292-293
Author(s):  
Charlotte L. Ownby ◽  
David Cameron ◽  
Anthony T. Tu
Keyword(s):  
Gel Filtration ◽  
Microscopic Analysis ◽  
The United States ◽  
Exchange Chromatography ◽  
Pure Component ◽  
Electron Microscopic Level ◽  
Electron Microscopic ◽  
Mouse Muscle ◽  
Major Health Problem ◽  
Rattlesnake Venom

In the United States the major health problem resulting from snakebite poisoning is local tissue damage, i.e. hemorrhage and myonecrosis. Since commercial antivenin does not usually prevent such damage to tissue, a more effective treatment of snakebite-induced myonecrosis is needed. To aid in the development of such a treatment the pathogenesis of myonecrosis induced by a pure component of rattlesnake venom was studied at the electron microscopic level.The pure component, a small (4,300 mol. wt.), basic (isoelectric point of 9.6) protein, was isolated from crude prairie rattlesnake (Crotalus viridis viridis) venom by gel filtration (Sephadex G-50) followed by cation exchange chromatography (Sephadex C-25), and shown to be pure by electrophoresis. Selection of the myotoxic component was based on light microscopic observations of injected mouse muscle.

Studies on an Inhibitor of Plasminogen Activation in Human Serum

1973 ◽  
Vol 30 (02) ◽  
pp. 414-424 ◽  
Author(s):  
Ulla Hedner
Keyword(s):  
Ion Exchange ◽  
Human Serum ◽  
Antithrombin Iii ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Specific Adsorption ◽  
Partial Purification ◽  
Plasminogen Activation ◽  
Preparative Electrophoresis

SummaryA procedure is described for partial purification of an inhibitor of the activation of plasminogen by urokinase and streptokinase. The method involves specific adsorption of contammants, ion-exchange chromatography on DEAE-Sephadex, gel filtration on Sephadex G-200 and preparative electrophoresis. The inhibitor fraction contained no antiplasmin, no plasminogen, no α1-antitrypsin, no antithrombin-III and was shown not to be α2 M or inter-α-inhibitor. It contained traces of prothrombin and cerulo-plasmin. An antiserum against the inhibitor fraction capable of neutralising the inhibitor in serum was raised in rabbits.

Preparation and Characterization of NH2-Terminal Fibrinogen Bβ Fragments from N-DSK of Human Fibrinogen

1984 ◽  
Vol 51 (01) ◽  
pp. 016-021 ◽  
Author(s):  
S Birken ◽  
G Agosto ◽  
B Lahiri ◽  
R Canfield
Keyword(s):  
High Performance ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Reverse Phase ◽  
Human Fibrinogen ◽  
Human Volunteers ◽  
Cnbr Cleavage ◽  
Two Peaks

SummaryIn order to investigate the early release of NH2-terminal plasmic fragments from the Bβ chain of fibrinogen, substantial quantities of Bβ 1-42 and Bβ 1-21 are required as immunogens, as radioimmunoassay standards and for infusion into human volunteers to determine the half-lives of these peptides. Towards this end methods that employ selective proteolytic cleavage of these fragments from fibrinogen have been developed. Both the N-DSK fragment, produced by CNBr cleavage of fibrinogen, and Bβ 1-118 were employed as substrates for plasmin with the finding of higher yields from N-DSK. Bβ 1-42 and Bβ 1-21 were purified by gel filtration and ion-exchange chromatography on SP-Sephadex using volatile buffers. When the purified preparation of Bβ 1-42 was chromatographed on reverse-phase high performance liquid chromatography, two peaks of identical amino acid composition were separated, presumably due either to pyroglutamate or to amide differences.

Bovine Factors X1And X2: Activation Peptide Based Chromatographic Differences

1979 ◽  
Author(s):  
Takashi Morita ◽  
Craig Jackson
Keyword(s):  
Amino Acid ◽  
Anion Exchange ◽  
Gel Filtration ◽  
Heart Association ◽  
Personal Communication ◽  
Exchange Chromatography ◽  
Amino Acid Sequences ◽  
Factor X ◽  
Activation Peptide ◽  
Activation Peptides

Bovine Factor X is eluted in two forms (X1and X2) from anion exchange chromatographic columns. These two forms have indistinguishable amino acid compositions, molecular weights and specific activities. The amino acid sequences containing the γ-carboxyglutamic acid residues have been shown to be identical in X1 and X2(H. Morris, personal communication). An activation peptide is released from the N-terminal region of the heavy chain of Factor X by an activator from Russell’s viper venom. This peptide can be isolated after activation by gel filtration on Sephadex G-100 under nondenaturing conditions. The activation peptides from a mixture of Factors X1 and X2 were separated into two forms by anion-exchange chromatography. The activation peptide (AP1) which eluted first was shown to be derived from Factor X1. while the activation peptiae (AP2) which eluted second was shown to be derived from X2 on the basis of chromatographic separations carried out on Factors X1 and X2 separately. Factor Xa was eluted as a symmetrical single peak. On the basis of these and other data characterizing these products, we conclude that the difference between X1 and X2 are properties of the structures of the activation peptides. (Supported by a grant HL 12820 from the National Heart, Lung and Blood Institute. C.M.J. is an Established Investigator of the American Heart Association).

Co-purification of bone resorbing activity and adenylate cyclase stimulating activity from human tumours associated with the humoral hypercalcaemia of malignancy

1987 ◽  
Vol 114 (1) ◽  
pp. 18-26 ◽  
Author(s):  
Chohei Shigeno ◽  
Itsuo Yamamoto ◽  
Shegiharu Dokoh ◽  
Megumu Hino ◽  
Jun Aoki ◽  
...  
Keyword(s):  
Bone Resorption ◽  
High Performance ◽  
Basic Protein ◽  
Gel Filtration ◽  
Exchange Chromatography ◽  
Protein Factor ◽  
Human Tumours ◽  
Acid Stable ◽  
Bone Resorbing Activity

Abstract. We have partially purified a tumour factor capable of stimulating both bone resorption in vitro and cAMP accumulation in osteoblastic ROS 17/2 cells from three human tumours associated with humoral hypercalcaemia of malignancy. Purification of tumour factor by sequential acid urea extraction, gel filtration and cation-exchange chromatography, reverse-phase high performance liquid chromatography followed by analytical isoelectric focussing provided a basic protein (pI > 9.3) with a molecular weight of approximately 13 000 as a major component of the final preparation which retained both the two bioactivities. Bone resorbing activity and cAMP-increasing activity in purified factor correlated with each other. cAMP-increasing activity of the factor was heat- and acid-stable, but sensitive to alkaline ambient pH. Treatment with trypsin destroyed cAMP-increasing activity of the factor. Synthetic parathyroid hormone (PTH) antagonist, human PTH-(3– 34) completely inhibited the cAMP-increasing activity of the factor. The results suggest that this protein factor, having its effects on both osteoclastic and osteoblastic functions, may be involved in development of enhanced bone resorption in some patients with humoral hypercalcaemia of malignancy.

Synthesis of hepatitis B surface antigen pre-S2 region fragments and studies on their immunogenicity

1988 ◽  
Vol 53 (11) ◽  
pp. 2952-2956 ◽  
Author(s):  
Bernard Lammek ◽  
Zbigniew Maćkiewicz ◽  
Izabela Derdowska ◽  
Hanna Świderska ◽  
Adam Nowosławski ◽  
...  
Keyword(s):  
Hepatitis B ◽  
Surface Antigen ◽  
Solid Phase ◽  
Hepatitis B Surface Antigen ◽  
Gel Filtration ◽  
Exchange Chromatography ◽  
Antigenic Determinants ◽  
Phase Method ◽  
Peptide Fragments ◽  
Humoral Immune

Two peptide fragments of hepatitis B surface antigen pre-S2 region were synthesized by the solid phase method. The peptides were purified by gel filtration or ion-exchange chromatography on Sephadex SP-C-25. Both peptides induced a cellular and humoral immune response in rabbits. The results showed that fragment 14-22 of pre-S2 region contains one of the antigenic determinants.

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