scholarly journals Immunological studies on the rat peripheral-type benzodiazepine acceptor

1991 ◽  
Vol 275 (2) ◽  
pp. 419-425 ◽  
Author(s):  
P N Moynagh ◽  
C J Bailey ◽  
S J Boyce ◽  
D C Williams

Photoaffinity labelling of rat adrenal mitochondrial preparations with [3H]PK 14105 resulted in a single 3H-labelled band on SDS/PAGE gels with an apparent-molecular-mass peak of 18 kDa. This represents a polypeptide associated with the peripheral-type benzodiazepine-binding site. Solubilization of photoaffinity-labelled membranes with 6 M-guanidine hydrochloride, followed by gel filtration and reversed-phase h.p.l.c. of the solubilized material, resulted in the purification to homogeneity of the [3H]PK 14105-labelled polypeptide. This purified polypeptide was used to raise a rabbit polyclonal antiserum which recognized the immunogen in pure form and exclusively recognized it in a crude preparation of rat adrenal mitochondria as judged by immunoblotting. By the same analysis the antiserum identified the corresponding polypeptide from rat kidney and salivary gland, demonstrating its cross-reactivity. Subsequent immunocytochemical studies localized the polypeptide to the cortex of the adrenal gland, the distal tubules of kidney, the interstitial cells of testis, the biliary epithelium of liver and the choroid plexus and ependyma cells within the brain. This selective localization within organs may provide an insight into the physiological role of the peripheral-type benzodiazepine acceptor.

1989 ◽  
Vol 256 (3) ◽  
pp. G517-G523 ◽  
Author(s):  
R. M. Batt ◽  
N. U. Horadagoda ◽  
L. McLean ◽  
D. B. Morton ◽  
K. W. Simpson

An intrinsic factor has been identified in the canine pancreas, and output and properties of this protein have been compared with those of gastric intrinsic factor in the dog. Mean concentrations of intrinsic factor and peak outputs per minute were approximately 5- to 10-fold higher in pure pancreatic juice after stimulation with secretin and cholecystokinin, respectively, than in pentagastrin-stimulated gastric juice. Purified gastric and pancreatic intrinsic factors had an identical molecular mass of 65 kDa, estimated by gel filtration on Sephacryl S-200, while sodium dodecyl sulfate-polyacrylamide gel electrophoresis demonstrated single bands corresponding to 53 kDa. Immunoblots showed that rabbit polyclonal antiserum to canine gastric intrinsic factor cross-reacted with canine pancreatic intrinsic factor. Gastric and pancreatic intrinsic factor-cyano[57Co]cobalamin complexes exhibited comparable association constants for ileal receptors in canine brush-border vesicles, while there was minimal binding to jejunal vesicles. These findings demonstrate that the canine pancreas is an important source of an intrinsic factor that closely resembles gastric intrinsic factor in the dog.


1991 ◽  
Vol 54 (2) ◽  
pp. 105-108 ◽  
Author(s):  
GWEN REYNOLDS ◽  
JAMES J. PESTKA

An immunochemical approach is described for the detection of versicolorin (VA) and other aflatoxin precursors in Aspergillus parasiticus cultures. VA was purified from A. parasiticus ATCC 36537 cultures by semipreparative high performance liquid chromatography and confirmed by mass spectrometry and ultraviolet (UV) absorption. To be rendered immunogenic, VA was converted to a hemiacetal and conjugated to bovine serum albumin (BSA) by reductive alkylation. Rabbit polyclonal antiserum prepared against the VA hemiacetal-BSA conjugate was employed in a competitive ELISA using VA hemiacetal-horseradish peroxidase conjugate as the marker ligand. Based on the amount of VA analogue required to inhibit binding by 50% in competitive ELISA, cross-reactivity relative to VA for VA hemiacetal, averufanin, averantin, norsolorinic acid, averufin, sterigmatocystin, and aflatoxin B1 were 106, 85, 7, 6, 2, <1, and <1%, respectively. The ELISA was used to monitor enhanced production of VA equivalents by A. parasiticus ATCC 36537 in a modified culture procedure. The VA antibody should be extremely useful in the biochemical and genetic investigation of aflatoxin biosynthesis.


1997 ◽  
Vol 9 (3) ◽  
pp. 237-243 ◽  
Author(s):  
Joaquim Segalés ◽  
Mariano Domingo ◽  
Gloria I. Solano ◽  
Carlos Pijoan

An avidin-biotin complex immunohistochemistry technique was developed to detect Haemophilus parasuis serovar 5 in experimentally infected 18-21-day-old conventional pigs, using a rabbit polyclonal antiserum. Seven of 10 intratracheally inoculated animals developed a low to medium degree of fibrinous polyserositis; meninges and pleura were the most severely affected areas. Haemophilus parasuis was recovered from 9 of 10 pigs; in 2 of them H. parasuis was isolated from tracheal swabs only. Positive immunohistochemistry results, mainly observed as free bacteria or bacteria within inflammatory cell cytoplasm in the fibrinopurulent exudate, were observed in 8 of 10 animals. Cross-reactivity with Actinobacillus pleuropneumoniae was detected but not with other gram-positive and gram-negative bacteria tested. This immunohistochemistry technique seemed to be at least as sensitive as microbiologic cultures and could be useful in studies of pathogenesis and retrospective diagnosis. However, cross-reactivity with A. pleuropneumoniae means that positive immunohistochemistry results in lung tissue from field cases would be dubious.


1999 ◽  
Vol 277 (2) ◽  
pp. G487-G494 ◽  
Author(s):  
Christopher R. Marino ◽  
Virginia Jeanes ◽  
Walter F. Boron ◽  
Bernhard M. Schmitt

The cellular mechanisms of [Formula: see text] secretion in the human pancreas are unclear. Expression of a Na+-[Formula: see text]cotransporter (NBC) mRNA has been observed recently, but the distribution and physiological role of the NBC protein are not known. Here we examined the expression and localization of NBC in human pancreas by Northern blot, immunoblot, and immunofluorescence microscopy. Rat kidney NBC probes detected a single 9.5-kb band by Northern blot. On immunoblots, two polyclonal antisera directed against different epitopes of rat kidney NBC identified a single ∼130-kDa protein. In cryosections of normal human pancreas, both antisera labeled basolateral membranes of large, morphologically identifiable ducts and produced a distinct labeling pattern in the remainder of the parenchyma. In double-labeling experiments, NBC immunoreactivity in the parenchyma colocalized with the Na+-K+pump, a basolateral marker. In contrast, NBC and cystic fibrosis transmembrane conductance regulator, an apical membrane marker, were detected within the same histological structures but at different subcellular localizations. The NBC antisera did not label acinar or islet cells. Our observations suggest that secretion of[Formula: see text] by human pancreatic duct cells involves the basolateral uptake of Na+and[Formula: see text] via NBC, an electrogenic Na+-[Formula: see text]cotransporter.


1991 ◽  
Vol 11 (11) ◽  
pp. 5389-5397 ◽  
Author(s):  
P Yaciuk ◽  
E Moran

Binding of a 300-kDa host cell protein (p300) is tightly correlated with the ability of the adenovirus E1A products to induce quiescent baby rat kidney cells to proliferate. We have generated rabbit polyclonal antibodies against p300 to characterize this protein further. We have found p300 to be a nuclear phosphoprotein that is actively synthesized in both quiescent and proliferating baby rat kidney cells. In partially purified mitotic cell populations, we observe a form of p300 with decreased electrophoretic mobility in sodium dodecyl sulfate-polyacrylamide gels that shares a nearly identical partial proteolytic digest pattern with p300. The slower-migrating form of p300 is greatly reduced by treating immune complexes with potato acid phosphatase. The relative stability and presence of p300 even in resting cells suggests that p300 has a basal cell function, but the appearance of differentially modified forms during the cell cycle suggests the possibility that p300 function is modulated specifically in growing cells.


1980 ◽  
Vol 58 (5) ◽  
pp. 385-391 ◽  
Author(s):  
F. Louis ◽  
H. Favre

1. The effect of the sodium content of the diet on the natriuretic activity of an extract from the kidneys was studied in non-expanded and volume-expanded rats. 2. The kidney tissue was homogenized and the supernatant fractionated by gel filtration on Sephadex G-25. A single low-molecular-weight fraction eluted after the salt possessed the natriuretic activity and was tested on a rat bioassay. 3. The natriuretic activity of the fraction obtained from the kidneys of non-expanded rats was related to the sodium intake. 4. After an acute extracellular volume expansion, the natriuretic activity obtained from the fraction extracted from the kidneys was much greater than before expansion and was related to the dietary intake of sodium.


2018 ◽  
Vol 101 (5) ◽  
pp. 1661-1663 ◽  
Author(s):  
Haisheng Zhang ◽  
Jing Xue ◽  
Huanxia Zhao ◽  
Xinshuai Zhao ◽  
Huanhuan Xue ◽  
...  

Abstract Background: The composition and sequence of amino acids have a prominent influence on the antioxidant activities of peptides. Objective: A series of isolation and purification experiments was conducted to explore the amino acid sequence of antioxidant peptides, which led to its antioxidation causes. Methods: The degreased apricot seed kernels were hydrolyzed by compound proteases of alkaline protease and flavor protease (3:2, u/u) to prepare apricot seed kernel hydrolysates (ASKH). ASKH were separated into ASKH-A and ASKH-B by dialysis bag. ASKH-B (MW < 3.5 kDa) was further separated into fractions by Sephadex G-25 and G-15 gel-filtration chromatography. Reversed-phase HPLC (RP-HPLC) was performed to separate fraction B4b into two antioxidant peptides (peptide B4b-4 and B4b-6). Results: The amino acid sequences were Val-Leu-Tyr-Ile-Trp and Ser-Val-Pro-Tyr-Glu, respectively. Conclusions: The results suggested that ASKH antioxidant peptides may have potential utility as healthy ingredients and as food preservatives due to their antioxidant activity. Highlights: Materials with regional characteristics were selected to explore, and hydrolysates were identified by RP-HPLC and matrix-assisted laser desorption ionization-time-of-flight-MS to obtain amino acid sequences.


2002 ◽  
Vol 283 (5) ◽  
pp. F912-F922 ◽  
Author(s):  
M.-M. Trinh-Trang-Tan ◽  
F. Lasbennes ◽  
P . Gane ◽  
N. Roudier ◽  
P. Ripoche ◽  
...  

UT-B1 is the facilitated urea transporter of red blood cells (RBCs) and endothelial cells of descending vasa recta in the kidney. Immunoblotting with a polyclonal antibody against the C-ter sequence of rat UT-B1 revealed UT-B1 as both nonglycosylated (29 kDa) and N-glycosylated (47.5 and 33 kDa) proteins in RBC membranes, kidney medulla, brain, and bladder in rat. In testis, UT-B1 was expressed only as a nonglycosylated protein of 47.5 kDa. Immunocytochemistry confirmed that the location of UT-B1 is restricted to descending vasa recta. In brain, UT-B1 protein was found in astrocytes and ependymal cells. Cell bodies and perivascular end feet of astrocytes were labeled in brain cortex, whereas astrocyte cell processes were labeled in corpus callosum. Flow cytometry analysis of RBCs revealed a good cross-reactivity of the antibody with mouse and human UT-B1. UT-B1 protein expression in rat kidney medulla was downregulated greatly by long-term [deamino-Cys1,d-Arg8]vasopressin infusion and moderately by furosemide treatment. This study discloses an uneven distribution of UT-B1 protein within astrocytes and the regulation of renal UT-B1 protein by antidiuretic hormone.


1976 ◽  
Vol 54 (8) ◽  
pp. 699-703 ◽  
Author(s):  
Peter H. Yu ◽  
Maria R. Kula ◽  
Hsin Tsai

Four natural protease inhibitors have been partially purified by heat treatment, ion-exchange chromatography and gel filtration from Neurospora crassa. The inhibitory activity has been estimated by measuring the inhibition of proteolysis of casein as well as by the protection of Neurospora tryptophan synthase from proteolytic inactivation. The inhibitors are all oligopeptides and possess molecular weights in the range 5000 – 24 000 and appear to be very specific to Neurospora proteases. They may be classified into two types. The first are specific to Neurospora alkaline protease and the second to acidic protease. None of them exhibited any effect on other proteases including trypsin, chymotrypsin, papain, pepsin, thermolysin, subtilisin and proteinase K. The possible physiological role of these inhibitors is discussed.


1993 ◽  
Vol 139 (1) ◽  
pp. 97-105
Author(s):  
P. R. Conliffe ◽  
H. P. J. Bennett ◽  
S. Mulay

ABSTRACT It was observed in the course of other studies that rat fetal lung extracts inhibited proliferation of fetal lung cells in culture. The purpose of the present study was to isolate and characterize this cytostatic factor. It was found that fetal lungs contained a 16 kDa cytostatic factor and its concentration was twofold greater in fetal lungs of diabetic rats compared with control rats. This fetal lung cytostatic protein (FLCP) was purified by reversed-phase, heparin-affinity and gel filtration high-performance liquid chromatography and SDS-PAGE. The purified protein was electroblotted onto polyvinylidene difluoride membrane and subjected to sequence analysis. The amino-terminal sequence of this fetal lung cytostatic protein was PEPAKSAPAPXKGIGKQXXKAX XKA... and showed significant homology with histone H2B; however, the amino acid composition of FLCP suggested that it may be structurally distinct from histone H2B. Ion-spray mass spectrometry suggested that FLCP was made up of at least two species of the protein with molecular weights of 13 776·1 and 14 007·3 and was different from the molecular weight of rat histone H2B predicted by its cDNA sequence. The concentration of FLCP, based on amino acid compositions, was 0·32 nmol/g and 0·83 nmol/g wet fetal lung from non-diabetic and diabetic rats respectively. These findings suggest that the fetal rat lung produces a regulatory factor bearing considerable homology with but possibly different from histone H2B and that fetal lung immaturity during diabetic pregnancy might be contributed to by an increase in this factor. Journal of Endocrinology (1993) 139, 97–105


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