Effects of acute hepatic ischemia on the electrophoretic patterns of the polypeptides and phosphopolypeptides of the microsomal membrane fraction of rat liver

1980 ◽  
Vol 58 (10) ◽  
pp. 1039-1050 ◽  
Author(s):  
Monique Behar-Bannelier ◽  
Les Pinteric ◽  
Robert K. Murray
Keyword(s):  
Rat Liver ◽  
Membrane Fraction ◽  
Sodium Dodecyl ◽  
Microsomal Membrane ◽  
Male Rats ◽  
Base Line ◽  
Hepatic Ischemia ◽  
Electrophoretic Patterns

The purpose of this study was to establish when alterations of the electrophoretic patterns of the polypeptides and phosphopolypeptides of the microsomal membrane fraction of the livers of rats become observable after initiation of acute hepatic ischemia. Ischemia was initiated by clamping the vascular supply to the left and median lobes of the livers of adult male rats. The animals were killed at various times thereafter (up to 6 h, and in certain instances, 24 h) and microsomal membrane fractions were prepared from each. The patterns of the polypeptides and phosphopolypeptides of these fractions were analysed by sodium dodecyl sulfate – polyacrylamide gel electrophoresis, using staining with Coomassie blue to analyse the polypeptides and radioautography to analyse 32P-labelled phosphopolypeptides. Alterations of the polypeptide pattern were apparent in the fractions from animals killed at 4 h and after; prior to this time point, subtle alterations, at most, could be distinguished. Effects of acute ischemia on the pattern of phosphopolypeptides of the microsomal membrane fraction were studied after phosphorylation in vivo (produced by intraperitoneal injection of [32P]phosphoric acid) and in vitro (using [γ-32P]ATP as phosphate donor). No marked changes in the phosphopolypeptide pattern produced by phosphorylation in vivo were observed until 6 h after clamping, by which time a diminution of the radioactivity in the majority of the phosphopolypeptides was evident. However, noteworthy alterations of the pattern of phosphopolypeptides produced by phosphorylation in vitro were observable in the membrane fractions from animals subjected to 2 h of ischemia. Overall the study provides a base line delineating the time sequence during which alterations of the electrophoretic patterns of the polypeptides and phosphopolypeptides of rat liver microsomal membranes become evident following the onset of acute hepatic ischemia and reveals that gross alterations of the polypeptide patterns of these membranes and of certain other subcellular fractions are not an early occurrence following this severe type of injury. The possible utility of the application of phosphorylation in vitro for detecting early alterations in membrane structure following cell injury is suggested.

scholarly journals Biogenesis of microsomal membrane glycoproteins in rat liver. II. Purification of soluble glycoproteins and their incorporation into microsomal membranes.

1975 ◽  
Vol 67 (3) ◽  
pp. 700-714 ◽  
Author(s):  
F Autuori ◽  
H Svensson ◽  
G Dallner
Keyword(s):  
Rat Liver ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Exchange Chromatography ◽  
Microsomal Membrane ◽  
Membrane Glycoproteins ◽  
In Vivo Labeling ◽  
Microsomal Membranes

Sialoproteins isolated from the soluble fraction of rat liver could be incorporated into microsomal membranes. This incorporation was dependent on protein concentration, time, and temperature. Sodium dodecyl sulfate gel electrophoresis of membrane proteins after in vitro incorporation showed four major sugar-containing peaks and was similar to that found after in vivo labeling. Most of the incorporated protein was tightly bound to the microsomal membrane. Gel filtration and ion-exchange chromatography revealed the presence of several cytosolic glycoproteins that could be incorporated into microsomes. During prolonged centrifugation in a KBr solution with a density of 1.21 a highly labeled ([3H]glucosamine) protein (mole wt approximately to 70,000) that was actively incorporated into microsomes could be recovered in the upper region of the tube. These results demonstrate that several cytoplasmic glycoproteins of rat liver are transferred into microsomal membranes and that one of these is a lipoprotein.

Effects of in vivo gonadal hormone environment on in vitro hGRF-40-stimulated GH release

1985 ◽  
Vol 249 (3) ◽  
pp. E276-E280 ◽  
Author(s):  
W. S. Evans ◽  
R. J. Krieg ◽  
E. R. Limber ◽  
D. L. Kaiser ◽  
M. O. Thorner
Keyword(s):  
Female Rats ◽  
Male Rats ◽  
Gonadal Hormone ◽  
Base Line ◽  
Pituitary Cells ◽  
Intact Male ◽  
Castrate Male ◽  
Basal Release

The effects of gender and the gonadal hormone environment on basal and stimulated growth hormone (GH) release by dispersed and continuously perifused rat anterior pituitary cells were examined. Cells from intact male and diestrus day 2 female rats and from castrate male rats either untreated or treated with testosterone (T) or 17 beta-estradiol (E2) were used. Basal GH release (ng/min per 10(7) cells; mean +/- SE) by cells from diestrus day 2 female rats was less than by cells from castrate rats treated with T (4.3 +/- 0.6 vs. 11.4 +/- 2.7, respectively; P less than 0.025). No other differences in basal release were detected. Concentration-response relationships were documented between human GH-releasing factor 40 (hGRF-40; 0.03-100 nM given as 2.5-min pulses every 27.5 min) and GH release. Mean (+/- SE) overall GH release (ng/min per 10(7) cells) above base line was greater by cells from intact male rats (496 +/- 92) than by cells from castrate (203 +/- 37.3; P less than 0.0001), castrate and T-treated (348 +/- 52.8; P = 0.008), or castrate and E2-treated (58.1 +/- 6.8; P less than 0.001) male rats or by diestrus day 2 rats (68.6 +/- 9.5; P = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Role of membrane-bound and free polyribosomes in the synthesis of cytochrome c in rat liver

1974 ◽  
Vol 140 (2) ◽  
pp. 157-167 ◽  
Author(s):  
Néstor F. González-Cadavid ◽  
Carmen Sáez De Córdova
Keyword(s):  
Endoplasmic Reticulum ◽  
Cytochrome C ◽  
Rat Liver ◽  
Cell Structure ◽  
Polyacrylamide Gel Electrophoresis ◽  
Mitochondrial Protein ◽  
Sodium Dodecyl ◽  
Membrane Bound

The functional distinction of membrane-bound and free polyribosomes for the synthesis of exportable and non-exportable proteins respectively is not so strict as was initially thought, and it was therefore decided to investigate their relative contribution to the elaboration of an internal protein integrated into a cell structure. Cytochrome c was chosen as an example of a soluble mitochondrial protein, and the incorporation of [14C]leucine and δ-amino[14C]laevulinate into the molecule was studied by using different ribosomal preparations from regenerating rat liver. A new procedure was devised for the purification of cytochrome c, based on ion-exchange chromatography combined with sodium dodecyl sulphate–polyacrylamide-gel electrophoresis. In spite of cytochrome c being a non-exportable protein, the membrane-bound polyribosomes were at least as active as the free ribosomes in the synthesis in vitro of the apoprotein and the haem moiety. The detergent-treated ribosomes could also effect the synthesis of cytochrome c, although at a lower rate. Since in liver more than two-thirds of the ribosomes are bound to the endoplasmic-reticulum membranes, it is considered that in vivo they are responsible for the synthesis of most of the cytochrome c content of the cell. This suggests that in secretory tissues the endoplasmic reticulum plays a predominant role in mitochondrial biogenesis, although free ribosomes may participate in the partial turnover of some parts of the organelle. The hypothesis on the functional specialization of the different kinds of ribosomes was therefore modified to account for their parallel intervention in the synthesis of proteins associated with membranous structures.

scholarly journals Metabolism and Tissue Distribution of Chelerythrine and Effects of Macleaya Cordata Extracts on Liver NAD(P)H Quinone Oxidoreductase

2021 ◽  
Vol 8 ◽  
Author(s):  
Chong-Yin Huang ◽  
Ya-Jun Huang ◽  
Zhuo-Yi Zhang ◽  
Yi-Song Liu ◽  
Zhao-Ying Liu
Keyword(s):  
Tissue Distribution ◽  
Rat Liver ◽  
Metabolic Pathway ◽  
Male Rats ◽  
Intragastric Administration ◽  
Main Metabolic Pathway ◽  
Macleaya Cordata ◽  
The Impact

Background:Macleaya cordata (Willd.) (Papaveraceae) is listed as a feed additive in animal production by the European Food Authority.Methods: The metabolites of chelerythrine in rats were measured in vitro and in vivo by rapid and accurate high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (HPLC/QqTOF-MS). The structures of CHE metabolites were elucidated by comparing their changes in accurate molecular masses and fragment ions with those of parent ion or metabolite. The metabolic enzymes that were involved in chelerythrine reduction were investigated using an inhibition method. The tissue distribution of chelerythrine and the effects on NQO1 following intragastric administration with M. cordata extracts in rats were examined.Results: A total of twelve metabolites of chelerythrine were characterized by this approach in rat liver S9 and in vivo. The reduction of the iminium bond of chelerythrine and subsequent O-demethylation was the main metabolic pathway of chelerythrine in rat liver S9 while the reduction of the iminium bond of chelerythrine was the main metabolic pathway of chelerythrine in rats in vivo. After the rats were given intragastric administration, the low concentration residues of sanguinarine and chelerythrine in different rat tissues were found at 48 h after the last dose, suggesting that both compounds could be widely distributed in tissues. The results also indicated that XO, NQO1, NQO2, and carbonyl reductase are involved in chelerythrine reduction. Macleaya cordata extracts treated female and male rats, respectively, showed different responses, inhibiting NQO1 activity in males, but inducing NQO1 activity in females. Chelerythrine had a weak impact on NQO1 activity, but sanguinarine inhibited NQO1 activityConclusion: Through studying the effects of cytosolic reductase inhibitors on chelerythrine reduction and the impact of chelerythrine and sanguinarine on the activity of NQO1 in vitro and in vivo, we clarified the potential drug interaction of Macleaya cordata extract in clinical application, so as to provide theoretical guidance for clinically safe medication. In addition, it provided a reference basis for the metabolic mechanism of chelerythrinein rats.

Glucocorticoid–dependent maintenance of CYP2C11–dependent oxidation in male rat liver in vivo

2000 ◽  
Vol 19 (2) ◽  
pp. 126-131 ◽  
Author(s):  
M Murray
Keyword(s):  
Rat Liver ◽  
Male Rats ◽  
Male Rat ◽  
Hormonal Factors ◽  
Adrenal Hormones ◽  
Male Specific ◽  
Physiological Correlate ◽  
Made In

1 Hormonal factors participate in the regulation of xenobiotic metabolising enzymes in liver. Hepatic xenobiotic oxidation capacity is decreased in adrena-lectomised rats, which directly implicates adrenal hormones in the control of cytochrome P450 (CYP) expression. In addition, recent studies in cultured hepatocytes have demonstrated that low concentra-tions of glucocorticoid upregulate the male-specific CYP2C11, which is a major enzyme that catalyses xenobiotic and steroid hydroxylations in rat liver. The present study evaluated whether glucocorticoid or mineralocorticoid may be the adrenal factor that contributes to the in vivo expression of CYP2C11 in liver. 2 Adrenalectomy of male rats selectively decreased CYP2C11-dependent 2a-/16a-hydroxylation of testos-terone and other steroid substrates to 60-70% of control, whereas activities mediated by other constitu-tive CYPs were unaffected. The decrease in CYP2C11 activity was due to impaired protein expression in liver after adrenalectomy. Administration of dexametha-sone (DEX; 0.2 mg/kg i.p. daily for 6 days) restored CYP2C11 activity and protein, whereas the mineralo-corticoid deoxycorticosterone (DOC) and adrenocorti-cotropic hormone (ACTH) were ineffective. 3 These findings establish that glucocorticoids have a partial role in the maintenance of CYP2C11 expression and associated microsomal oxidation in liver and provide a physiological correlate for similar observa-tions made in vitro in hepatocyte culture.

Effect of X-irradiation on gene expression of rat liver chemokines: in vivo and in vitro studies

2008 ◽  
Vol 46 (01) ◽  
Author(s):  
F Moriconi ◽  
H Christiansen ◽  
H Christiansen ◽  
N Sheikh ◽  
J Dudas ◽  
...  
Keyword(s):  
Gene Expression ◽  
Rat Liver ◽  
In Vitro Studies ◽  
X Irradiation

scholarly journals Effective decellularisation of human saphenous veins for biocompatible arterial tissue engineering applications: Bench optimisation and feasibility in vivo testing

2021 ◽  
Vol 12 ◽  
pp. 204173142098752
Author(s):  
Nadiah S Sulaiman ◽  
Andrew R Bond ◽  
Vito D Bruno ◽  
John Joseph ◽  
Jason L Johnson ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Mechanical Strength ◽  
Vascular Tissue ◽  
Sodium Dodecyl ◽  
Host Cells ◽  
Replacement Model ◽  
In Vivo Testing ◽  
Vascular Scaffolds

Human saphenous vein (hSV) and synthetic grafts are commonly used conduits in vascular grafting, despite high failure rates. Decellularising hSVs (D-hSVs) to produce vascular scaffolds might be an effective alternative. We assessed the effectiveness of a detergent-based method using 0% to 1% sodium dodecyl sulphate (SDS) to decellularise hSV. Decellularisation effectiveness was measured in vitro by nuclear counting, DNA content, residual cell viability, extracellular matrix integrity and mechanical strength. Cytotoxicity was assessed on human and porcine cells. The most effective SDS concentration was used to prepare D-hSV grafts that underwent preliminary in vivo testing using a porcine carotid artery replacement model. Effective decellularisation was achieved with 0.01% SDS, and D-hSVs were biocompatible after seeding. In vivo xeno-transplantation confirmed excellent mechanical strength and biocompatibility with recruitment of host cells without mechanical failure, and a 50% patency rate at 4-weeks. We have developed a simple biocompatible methodology to effectively decellularise hSVs. This could enhance vascular tissue engineering toward future clinical applications.

scholarly journals Stamina-Enhancing Effects of Human Adipose-Derived Stem Cells

2021 ◽  
Vol 30 ◽  
pp. 096368972110354
Author(s):  
Eun-Jung Yoon ◽  
Hye Rim Seong ◽  
Jangbeen Kyung ◽  
Dajeong Kim ◽  
Sangryong Park ◽  
...  
Keyword(s):  
Physical Activity ◽  
Stem Cells ◽  
Locomotor Activity ◽  
Tissue Injury ◽  
Male Rats ◽  
Adipose Derived Stem Cells ◽  
Sprague Dawley ◽  
Serum Triglycerides

Stamina-enhancing effects of human adipose derived stem cells (hADSCs) were investigated in young Sprague-Dawley rats. Ten-day-old male rats were transplanted intravenously (IV) or intracerebroventricularly (ICV) with hADSCs (1 × 106 cells/rat), and physical activity was measured by locomotor activity and rota-rod performance at post-natal day (PND) 14, 20, 30, and 40, as well as a forced swimming test at PND 41. hADSCs injection increased the moving time in locomotor activity, the latency in rota-rod performance, and the maximum swimming time. For the improvement of physical activity, ICV transplantation was superior to IV injection. In biochemical analyses, ICV transplantation of hADSCs markedly reduced serum creatine phosphokinase, lactate dehydrogenase, alanine transaminase, and muscular lipid peroxidation, the markers for muscular and hepatic injuries, despite the reduction in muscular glycogen and serum triglycerides as energy sources. Notably, hADSCs secreted brain-derived neurotrophic factor (BDNF) and nerve growth factor in vitro, and increased the level of BDNF in the brain and muscles in vivo. The results indicate that hADSCs enhance physical activity including stamina not only by attenuating tissue injury, but also by strengthening the muscles via production of BDNF.

Sign in / Sign up

Export Citation Format

Share Document