Estrogen sulfotransferase distribution in tissues of mouse and guinea pig: steroidal inhibition of the guinea pig enzyme

1992 ◽  
Vol 70 (8) ◽  
pp. 712-715 ◽  
Author(s):  
Ronald Hobkirk ◽  
Mary Ann Glasier
Keyword(s):  
Guinea Pig ◽  
Enzyme Inhibition ◽  
Specific Activity ◽  
Total Activity ◽  
Fetal Membrane ◽  
Estrogen Sulfotransferase ◽  
Structural Specificity ◽  
Specific Activities

The highest total activity of estrogen sulfotransferase in guinea pig is in liver and the highest specific activities are in the adrenal and the midgestational chorion. Guinea pig gonads contain scarcely detectable activities. In CD-1 mice the highest specific activity is in testis and the highest total activity is in late placenta. Adrenals from both sexes and ovaries contain minimal activities, while liver and fetal membrane activities are remarkably low. In CD-1, DBA, C57BL, and BALB mice, qualitative patterns are similar. Purified or partially purified estrogen sulfotransferase from guinea pig adrenal and chorion were used to study the effect of a number of possible steroidal inhibitors. Considerable structural specificity is evident within a range of steroids, even among some which are not substrates. Pregnenolone is the most effective 21-carbon inhibitor and, in general, more highly hydroxylated forms are less inhibitory. Within a series of 21-, 19- and 18-carbon steroids, the structure of the A ring appears to be extremely important in regard to inhibitory effects.Key words: estrogen sulfotransferase, mouse, guinea pig, enzyme inhibition, steroids.

A Comparative Study of the Distribution of Soluble and Particulate Glycyl-l-Leucine Hydrolase in the Small Intestine

1974 ◽  
Vol 46 (4) ◽  
pp. 501-510
Author(s):  
Manjusri Das ◽  
A. N. Radhakrishnan
Keyword(s):  
Enzyme Activity ◽  
Guinea Pig ◽  
Comparative Study ◽  
Specific Activity ◽  
Maximal Activity ◽  
Total Activity ◽  
Soluble Enzyme ◽  
Km Value ◽  
Specific Activities ◽  
Very High

1. A comparative study has been made of glycyl-l-leucine hydrolase activity in the soluble and particulate fractions of intestinal mucosa from monkey, guinea-pig, rabbit and rat. The specific activity of the soluble enzyme is very high in monkey and guinea-pig, and lower in rabbit and rat. The particulate enzymes from all the four species show low specific activities and form 1–10% of the total activity. 2. The pH optima in all cases lie in the range 7·6–7·8. The Km values of the substrate were similar for both soluble and particulate enzyme from monkey and guinea-pig, but in the rabbit and rat the Km value with the particulate enzyme was higher than with the soluble enzyme. 3. The particulate enzyme activity in all cases was the highest in the distal regions of the intestine, whereas the soluble enzyme showed maximal activity in the proximal and middle regions.

An International Collaborative Study to Investigate Standardisation of Hirudin Potency

1993 ◽  
Vol 69 (05) ◽  
pp. 430-435 ◽  
Author(s):  
Colin Longstaff ◽  
Man-Yu Wong ◽  
Patrick J Gaffney
Keyword(s):  
Specific Activity ◽  
Collaborative Study ◽  
Residual Activity ◽  
Quality Standard ◽  
Upper Limit ◽  
Assay Procedure ◽  
Specific Activities ◽  
International Collaborative ◽  
Range Of Values ◽  
International Collaborative Study

SummaryAn international collaborative study has been carried out to investigate the reproducibility of hirudin assays in 13 laboratories using four recombinant hirudins and one natural, sulphated product. A simple assay procedure was proposed involving the titration of α-thrombin with inhibitor and measurement of residual activity using a chromogenic substrate. A standard α-thrombin preparation was supplied to ensure that this reagent was of uniform quality throughout the study. The method appeared to present no difficulties and laboratories reported similar potencies for the 5 hirudin samples, in line with expected values. This gave 200–222 Thrombin Inhibitory Units/ampoule (TIU/ampoule) of lyophilised hirudin, with geometric coefficient of variation (gcv) values ranging from 10.15–15.97%. This corresponds to specific activities of approximately 14,300–15,900 TIU/mg protein. This is close to the upper limit of previously reported values of specific activity. We conclude that the precision of this determination compared with the wider range of values in the literature (8,000–16,000 thrombin inhibitory units [TIU]/mg) results from the use of good quality standard α-thrombin by all laboratories. This study has important implications for hirudin standardisation.

scholarly journals Gut Digestive Function and Microbiome after Correction of Experimental Dysbiosis in Rats by Indigenous Bifidobacteria

2021 ◽  
Vol 9 (3) ◽  
pp. 522
Author(s):  
Lyudmila V. Gromova ◽  
Elena I. Ermolenko ◽  
Anastasiya L. Sepp ◽  
Yulia V. Dmitrieva ◽  
Anna S. Alekseeva ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Digestive Enzymes ◽  
Specific Activity ◽  
Control Group ◽  
Enteropathogenic Escherichia Coli ◽  
Beneficial Bacteria ◽  
Opportunistic Bacteria ◽  
Dyspeptic Symptoms ◽  
Specific Activities ◽  
Impaired Motor Function

In recent years, great interest has arisen in the use of autoprobiotics (indigenous bacteria isolated from the organism and introduced into the same organism after growing). This study aimed to evaluate the effects of indigenous bifidobacteria on intestinal microbiota and digestive enzymes in a rat model of antibiotic-associated dysbiosis. Our results showed that indigenous bifidobacteria (the Bf group) accelerate the disappearance of dyspeptic symptoms in rats and prevent an increase in chyme mass in the upper intestine compared to the group without autoprobiotics (the C1 group), but significantly increase the mass of chyme in the colon compared to the C1 group and the control group (healthy animals). In the Bf group in the gut microbiota, the content of opportunistic bacteria (Proteus spp., enteropathogenic Escherichia coli) decreased, and the content of some beneficial bacteria (Bifidobacterium spp., Dorea spp., Blautia spp., the genus Ruminococcus, Prevotella, Oscillospira) changed compared to the control group. Unlike the C1 group, in the Bf group there was no decrease in the specific activities of maltase and alkaline phosphatase in the mucosa of the upper intestine, but the specific activity of maltase was decreased in the colon chyme compared to the control and C1 groups. In the Bf group, the specific activity of aminopeptidase N was reduced in the duodenum mucosa and the colon chyme compared to the control group. We concluded that indigenous bifidobacteria can protect the microbiota and intestinal digestive enzymes in the intestine from disorders caused by dysbiosis; however, there may be impaired motor function of the colon.

scholarly journals THE Ah PHENOTYPE. SURVEY OF FORTY-EIGHT RAT STRAINS AND TWENTY INBRED MOUSE STRAINS

Genetics ◽  
1982 ◽  
Vol 100 (1) ◽  
pp. 79-87
Author(s):  
Daniel W Nebert ◽  
Nancy M Jensen ◽  
Hisashi Shinozuka ◽  
Heinz W Kunz ◽  
Thomas J Gill
Keyword(s):  
Specific Activity ◽  
Inbred Mouse ◽  
Inbred Mouse Strain ◽  
Mouse Strains ◽  
Ah Receptor ◽  
Inbred Mouse Strains ◽  
Sprague Dawley ◽  
Rat Strains ◽  
Specific Activities ◽  
Inbred Rat

ABSTRACT Forty-four inbred and four randombred rat strains and 20 inbred mouse strains were examined for their Ah phenotype by determining the induction of liver microsomal aryl hydrocarbon (benzo[a]pyrene) hydroxylase activity (EC 1.14.14.1) by intraperitoneal treatment with either β-naphthoflavone or 3-methylcholanthrene. All 48 rat strains were found to be Ah-responsive. The maximally induced hydroxylase specific activities of the ALB/Pit, MNR/Pit, MR/Pit, SHR/Pit, and Sprague-Dawley strains were of the same order of magnitude as the basal hydroxylase specific activities of the ACI/Pit, F344/Pit, OKA/Pit, and MNR/N strains. Six of the 20 mouse strains were Ah-nonresponsive (i.e. lacking the normal induction response and presumably lacking detectable amounts of the Ah receptor). The basal hydroxylase specific activities of the BDL/N, NFS/N, STAR/N, and ST/JN mouse strains were more than twice as high as the maximally induced hydroxylase specific activity of the CBA/HT strain.——To date, 24 Ah-nonresponsive mouse strains have been identified, out of a total of 68 known to have been characterized. The reasons for not finding a single Ah-nonresponsive inbred rat strain—as compared with about one Ah-nonresponsive inbred mouse strain found for every three examined—remain unknown.

Carbohydrase activity in the pancreatic tissue and small intestine mucosa of sheep fed dried-grass or ground maize-based diets

1985 ◽  
Vol 104 (2) ◽  
pp. 435-443 ◽  
Author(s):  
A. N. Janes ◽  
T. E. C. Weekes ◽  
D. G. Armstrong
Keyword(s):  
Small Intestine ◽  
Amylase Activity ◽  
Total Activity ◽  
Pancreatic Tissue ◽  
Proximal Region ◽  
Small Intestinal Mucosa ◽  
Intestine Mucosa ◽  
Ruminant Animals ◽  
Specific Activities ◽  
Small Intestinal

SummaryTwo groups of six sheep were fed either dried-grass or ground maize-based diets for at least 4 weeks before slaughter. Samples of the small intestinal mucosa and spancreatic tissue were assayed for a-amylase, glucoamylase, maltase and oligo-l,6-glucosidase.The pancreatic tissue contained high activities of α-amylase and much lower activities of glucoamylase, maltase and oligo-1,6-glucosidase. There was no effect of diet on the specific activities of any of these enzymes in the pancreatic tissue.The activity of α-amylase adsorbed on to the mucosa of the small intestine was greatest in the proximal region of the small intestine, the activity generally declining with increasing distance away from the pylorus. There was no diet effect on the absorbed α-amylase activity.Similar patterns of distribution along the small intestine were observed for maltase, glucoamylase and oligo-1,6-glucosidase with the highest activities in t he jejunum. There was no overall effect of diet on glucoamylase or maltase specific activities and glucoamylase total activity, although the total activities of maltase and oligo-1,6-glucosidase were significantly greater for the sheep fed the ground maize-based diet (P < 0·05).It is suggested that ruminant animals may be capable of digesting large amounts of starch in the small intestine through an adaptation in the activity of the host carbohydrases.

The identification of acetyl-l-carnitylcholine in rat brain extracts and the comparison of its cholinomimetic properties with acetylcholine

1970 ◽  
Vol 48 (10) ◽  
pp. 709-722 ◽  
Author(s):  
E. A. Hosein ◽  
A. Kato ◽  
E. Vine ◽  
A. M. Hill
Keyword(s):  
Guinea Pig ◽  
Rat Brain ◽  
Total Activity ◽  
Guinea Pig Ileum ◽  
Molar Basis ◽  
Choline Esters ◽  
Brain Extracts

Acetyl-l-carnitylcholine (l-ACCh) was identified in rat brain extracts on paper chromatograms developed in butanol–water for 138 h. l-ACCh was also identified in brain extracts fractionated on t.l.c. plates and on Sephadex G-10 columns. In every instance l-ACCh was separated from the acetylcholine (ACh) present and the ACh-like activity of l-ACCh was about 20% of the total activity in the extract. Both l-ACCh and ACh were found to be inseparable in a variety of chromatographic systems including electrophoresis. Treatment of these choline esters with cholinesterases showed that while true acetylcholinesterase hydrolyzed both l-ACCh and ACh, pseudocholinesterase destroyed only ACh. On a molar basis, the ACh-like activity of ACCh is one-half that of ACh on both the guinea pig ileum and frog rectus preparations. Like ACh, the ratio of the nicotinic to muscarinic potency of l-ACCh is unity. Mixtures of l-ACCh and ACh show summation of ACh-like activity on both the guinea pig ileum and frog rectus preparations.

scholarly journals Regulation of lipogenic capacity in lactating rats

1982 ◽  
Vol 208 (3) ◽  
pp. 611-618 ◽  
Author(s):  
M R Grigor ◽  
A Geursen ◽  
M J Sneyd ◽  
S M Warren
Keyword(s):  
Mammary Gland ◽  
Fatty Acid ◽  
Malic Enzyme ◽  
Fatty Acid Synthase ◽  
Specific Activity ◽  
Mammary Glands ◽  
Lipogenic Enzymes ◽  
Pregnancy And Lactation ◽  
Specific Activities

1. The rate of mammary-gland lipogenesis measured in vivo from 3H2O was suppressed after decreasing the milk demand by decreasing the number of pups from ten to two or three, as well as by giving diets containing lipid [Grigor & Warren (1980) Biochem. J. 188, 61-65]. 2. The specific activities of the lipogenic enzymes fatty acid synthase, glucose 6-phosphate dehydrogenase and ‘malic’ enzyme increased between 6- and 10-fold in the mammary gland and between 2- and 3-fold in the livers during the first 10 days of lactation. The increases in specific activity coupled with the doubling of liver mass which occurred during pregnancy and lactation resulted in considerable differences in total liver activities when compared with virgin animals. 3. Although consumption of a diet containing 20% peanut oil suppressed the activities of the three lipogenic enzymes in the livers, only the ‘malic’ enzyme was affected in the mammary glands. 4. In contrast, decreased milk demand did not affect the specific activities of any of the liver enzymes, whereas it resulted in suppression of all three lipogenic enzymes of the mammary glands. There was no effect on either the cytoplasmic malate dehydrogenase or the lactate dehydrogenase of the mammary gland. 5. In all the experiments performed, the activity of the fatty acid synthase correlated with the amount of material precipitated by the rabbit antibody raised against rat fatty acid synthase.

5α-Reductase activity in stroma and epithelium of rat prostate and epididymis. A contribution to elucidation of the mechanism for development of hyperplastic growth of prostatic tissue

1983 ◽  
Vol 103 (2) ◽  
pp. 273-281 ◽  
Author(s):  
Ole Djøseland ◽  
Nicholas Bruchovsky ◽  
Paul S. Rennie ◽  
Navdeep Otal ◽  
Sian Høglo
Keyword(s):  
Enzyme Activity ◽  
Specific Activity ◽  
Reductase Activity ◽  
Major Change ◽  
Growth Stimulation ◽  
Total Activity ◽  
Prostatic Tissue ◽  
Ventral Prostate ◽  
Total Enzyme Activity ◽  
Abnormal Growth

Abstract. The 5α-reductase activity was assayed in homogenates of stroma and epithelium in the rat ventral prostate and epididymis. Samples consisting of 0.3 mg/ml tissue protein in TES buffer, pH 7.0 were incubated at 37°C for 30 min in the presence of 50 nm [1,2-3H]testosterone and a NADPH-generating system started with 5 × 10−4 m NADP. The yield of 5α-reduced metabolites, as established by using thin-layer chromatography, gave an estimate of enzyme activity. Whereas the specific activity of 5α-reductase was highest in prostatic stroma and epididymal epithelium, most of the total enzyme activity was associated with the epithelium in both the prostate and epididymis. The effect of dihydrotestosterone on specific activity of 5α-reductase was studied by administering the hormone to 7-day castrated rats. In prostate, the specific activity of both stromal and epithelium forms of the enzyme reached a maximum after 4 days of treatment. In epididymis only the epithelial form of 5α-reductase underwent a major change in specific activity, the latter peaking after 8–12 days of treatment. Furthermore, while the total activity of 5α-reductase in the prostatic tissue fractions could be induced by as much as 4-fold the normal control values, the epididymal enzyme could not be induced above the normal level either in the stroma or the epithelium. This may explain the relative resistance of epididymis to abnormal growth stimulation under the influence of hormones.

Estrogen sulfotransferase activity in guinea pig uterus and chorion

1983 ◽  
Vol 18 (1) ◽  
pp. 23-27 ◽  
Author(s):  
D.J. Freeman ◽  
F. Saidi ◽  
R. Hobkirk
Keyword(s):  
Guinea Pig ◽  
Estrogen Sulfotransferase

scholarly journals Partial purification of presynaptic plasma membrane by immunoadsorption.

1982 ◽  
Vol 94 (1) ◽  
pp. 88-96 ◽  
Author(s):  
G P Miljanich ◽  
A R Brasier ◽  
R B Kelly
Keyword(s):  
Plasma Membrane ◽  
Synaptic Vesicle ◽  
Nerve Terminal ◽  
Specific Activity ◽  
Electric Organ ◽  
Partial Purification ◽  
Vesicle Membrane ◽  
Specific Activities ◽  
Active Zones ◽  
Presynaptic Plasma Membrane

During transmitter release, synaptic vesicle membrane is specifically inserted into the nerve terminal plasma membrane only at specialized sites or "active zones." In an attempt to obtain a membrane fraction enriched in active zones, we have utilized the electric organ of the marine ray. From this organ, a fraction enriched in nerve terminals (synaptosomes) was prepared by conventional means. These synaptosomes were bound to microscopic beads by an antiserum to purified electric organ synaptic vesicles (anti-SV). The success of this immunoadsorption procedure was demonstrated by increased specific activities of bead-bound nerve terminal cytoplasmic markers and decreased specific activities of markers for contaminating membranes. To obtain a presynaptic plasma membrane (PSPM) fraction, we lysed the bead-bound synaptosomes by hypoosmotic shock and sonication, resulting in complete release of cytoplasmic markers. When the synaptosomal fraction was surface-labeled with iodine before immunoadsorption, 10% of this label remained bead-bound after lysis, compared with 2% of the total protein, indicating an approximately fivefold enrichment of bead-bound plasma membrane. Concomitantly, the specific activity of bead-bound anti-SV increased approximately 30-fold, indicating an enrichment of plasma membrane which contained inserted synaptic vesicle components. This PSPM preparation is not simply synaptic vesicle membrane since two-dimensional electrophoresis revealed that the polypeptides of the surface-iodinated PSPM preparation include both vesicle and numerous nonvesicle components. Secondly, antiserum to the PSPM fraction is markedly different from anti-SV and binds to external, nonvesicle, nerve terminal components.

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