Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The same isoenzyme of nonspecific alkaline phosphatase (APase), assayed with p-nitrophenylphosphate (p-NPP), was shown be present in different calcifying tissues, bone, calcifying cartilage, odontoblasts and enamel organ. Indications were also found that the enzymatic degradation of inorganic pyrophosphate (PPi) in calcifying tissues is mediated by APase. By using specific APase inhibitors, it was shown that two enzymes capable of degrading ATP exist. These were characterized in dentinogenically active odontoblasts, and it was concluded that one is the classical APase, the other is a Ca2+ and Mg2+ activated ATPase, named Ca2+-ATPase. The two phosphatases were solubilized from odontoblasts and separated. The localization of APase and Ca2+-ATPase in odontoblasts was investigated by subcellular fractionation and EM histochemistry. Routine methods for fixation were found to almost completely inactivate the enzymes. By using a mild fixation technique that preserved 80% of the enzyme activity, the main localization for both APase and Ca2+-ATPase was found to be in the membranes of intercellular vesicles located in the cell body and odontoblasts process. No activity was found in the cell membranes. It is concluded that there are at least two enzymes able to degrade phosphate compounds at alkaline pH in hard tissue forming cells. One is the nonspecific alkaline phosphatase (APase; EC 3. 1. 3. 1), which is active against p-NPP, PPi, glycerophosphates and ATP among other substrates. The other is a more specific Ca2+-ATPase (EC 3. 6. 1. 3). There seems to be an intimate relation between these two enzymes in the tissue. The function of APase in biological calcification is still obscure. In contrast, the finding of an ATP dependent, intravesicularly directed, transmembranous Ca2+-transport in vesicles derived from the microsomal fraction of odontoblasts may explain the role of Ca2+-ATPase.
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PMID:Odontoblast alkaline phosphatases and Ca2+ transport. 15 9

Corticotropin releasing factor (CRF) infused bilaterally into the lateral ventricles of awake, chronically cannulated, male Sprague-Dawley rats produced a dose-dependent increase in the in vitro activity of cortical and midbrain tryptophan hydroxylase after 60 min. The maximal increase in enzyme activity of 60% over that of vehicle-treated controls was reached 45 min after an infusion of 3 micrograms CRF. The increase in enzyme activity after a single dose of CRF resembled that seen after exposure of rats to an acute sound stress: it was reversed by preincubation of the enzyme preparation with alkaline phosphatase and was nonadditive with the increase in activity obtained in the presence of phosphorylating conditions. The response to intracerebroventricularly administered CRF was abolished by bilateral adrenalectomy, but restored by repeated daily systemic administration of the synthetic glucocorticoid, dexamethasone (500 micrograms/day, i.p. for 3 days), to the adrenalectomized rats. Intracerebroventricular administration of the glucocorticoid antagonist, RU 38486 (200 micrograms/day for 4 days), also blocked the acute increase in tryptophan hydroxylase activity in response to CRF. Finally, bilateral lesions to the central nucleus of the amygdala, a region involved in mediating behavioral, endocrine and autonomic responses to stressful stimuli, abolished the increase in enzyme activity in response to intraventricular CRF. The glucocorticoid sensitivity of the response to CRF, as well as the involvement of the central nucleus of the amygdala support the view that CRF may have a role in mediating the enhancement of tryptophan hydroxylase activity by acute sound stress.
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PMID:Increase in cortical and midbrain tryptophan hydroxylase activity by intracerebroventricular administration of corticotropin releasing factor: block by adrenalectomy, by RU 38486 and by bilateral lesions to the central nucleus of the amygdala. 130 22

From preclimacteric women (n = 10, 45-50 years of age) with gross cystic breast disease, levels of beta-endorphin, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, thyroid-stimulating hormone, cortisol and prolactin were assayed radiochemically in the breast cyst fluid and in plasma. The beta-endorphin concentration (fmol/ml) was increased more than fourfold in the breast cyst fluid (17.6 +/- 4.6 SEM) than in plasma (4.2 +/- 0.5 SEM). In the breast cyst fluid, estradiol was increased 41-fold (1738.2 +/- 350.5 SEM pg/ml), and progesterone 47-fold (65.47 +/- 8.25 SEM ng/ml) more than in plasma. The significantly increased values of beta-endorphin, estradiol and progesterone in the breast cyst fluid and the identification of beta-endorphin in cyst-lining epithelia demonstrate the local synthesis. Growth factor-like properties of beta-endorphin and estradiol are accountable for the propagation of cystic changes. The autonomic formation and function of beta-endorphin, estradiol and progesterone in cyst compartments can not be related with the levels of luteinizing hormone, follicle-stimulating hormone, thyroid-stimulating hormone and cortisol, which were significantly higher in plasma than in the breast cyst fluid. In the breast cyst fluid, prolactin could not detected to be significantly higher than in plasma. In addition the plasma-concentration of testosterone, androstenedione, thyroxin, triiodothyronine, thyroid-binding globulin, sexual-hormone-binding-globulin could be detected within the normal range. In this study we could demonstrate the synergism of beta-endorphin, steroid hormones and peptide hormones which advance the growth of gross cystic disease of preclimacteric women. Beta-endorphin was also examined by immunocytochemical assays (fluorescence, alkaline phosphatase and horseradish peroxidase method), in 11 women with pure fibrocystic disease, in 7 women with fibrocystic disease combined with a carcinoma in situ and in 15 women with fibrocystic disease combined with invasive carcinoma of the breast. Sections of frozen and paraffin embedded tissue of the same patient were reacted with anti-beta-endorphin antiserum. The immunoreactivity of beta-endorphin was intense in normal, proliferative altered and cyst-lining epithelia of fibrocystic disease and decreased in atypical epithelia and carcinoma cells of the breast. The degree of beta-endorphin staining is related to the degree of cell differentiation. In addition, nuclear receptors for estrogen and progesterone were assayed by peroxidase antiperoxidase technique.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[Interaction between beta-endorphin, steroids and peptide hormones in fibrocystic lesions of the female breast]. 164 46

In mineralizing dental tissues the non-specific alkaline phosphatase, using paranitrophenylphosphate (p-NPP) as substrate, is also capable of splitting inorganic pyrophosphate (PPi). In contrast to the p-NPP-ase part of the enzyme, the PPi-ase part requires Zn2+ as a cofactor for its hydrolytic activity. The PPi-ase activity of the enzyme can be inhibited by cadmium ions (Cd2+), perhaps by replacing Zn2+ from the active site of the enzyme molecule. In addition to splitting PPi, the PPi-ase part of the enzyme may also be involved in the phosphorylation process of yet undetermined organic macromolecules. Cd2+ inhibits this phosphorylation process. Inhibition of the PPi-ase activity can also be accomplished by ascorbic acid known for its capacity to complex bivalent cations. Ascorbic acid may accordingly also remove Zn2+ from the active site of the PPi-ase. It is suggested that in developing dental tissues alkaline phosphatase is not only associated with the transport of phosphate ions towards the mineralization front, but is also involved in the phosphorylation of organic macromolecules, a process activated the PPi-ase part of the enzyme.
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PMID:Possible functions of alkaline phosphatase in dental mineralization: cadmium effects. 165 1

Plasma adrenocorticotropin (ACTH) levels increase after acute cold exposure. The purpose of this study was to determine if there were parallel changes in pituitary proopiomelanocortin (POMC) mRNA. Male rats were exposed to cold (3-5 degrees C) or a novel environment for 15 or 30 min. Others were unstressed. POMC mRNAs in frozen sections or dissociated cells were hybridized with a photobiotinylated oligonucleotide probe which was detected in situ by streptavidin-alkaline phosphatase. The percentage of area labeled for POMC mRNA was quantified by the Cue-3 color image analysis system. In frozen sections, 24-fold increases in the percentage of area labeled for POMC mRNA were evident in intermediate lobes (IL) 30 min after stress. No change was seen in anterior lobes (AL). If the ALs were dissociated, a 66-99% increase in percentage of labeled cells was detected 2-3 hr after the cold exposure. Fifteen min of cold stress (CS) also caused a 117% increase in the area of label for POMC mRNA per corticotrope. No change was seen after 30 min. Exposure to a novel environment caused a 73% increase in the percentage of area labeled for POMC mRNA per AL corticotrope and an 11-fold increase in the IL. These results indicate that both AL corticotropes and IL melanotropes are stimulated by acute exposure to cold and novel environments.
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PMID:Changes in rat pituitary POMC mRNA after exposure to cold or a novel environment, detected by in situ hybridization. 185 78

A synthetic oligodeoxynucleotide sequence complementary to the mRNA for the adrenocorticotrophin (ACTH) precursor pro-opiomelanocortin (POMC) was end labelled using digoxigenin. The probe was used to detect POMC mRNA both on nitrocellulose filters and by non-isotopic in situ hybridisation (NISH) in tissue sections. Digoxigenin was identified using anti-digoxigenin alkaline phosphatase. The model system examined was the rat pituitary gland. Removal of both adrenal glands and dexamethasone administration were used to change the concentrations of POMC mRNA in the rat anterior lobe. The labelled probe reacted with a single band of appropriate molecular weight in Northern blot analysis. The distribution of signal in tissue sections and the changes induced by experimental manipulation were as predicted. The results indicate that this method of NISH will prove useful in the detection of specific messenger RNAs in tissue sections of buffered, formalin fixed, paraffin wax embedded material.
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PMID:Detection of messenger RNA using a digoxigenin end labelled oligodeoxynucleotide probe. 237 Mar 11

We studied the testis of Wistar rats weighing 280-300 gms. following the administration of a single, acute intracardiac dose of methionine-enkephalin (100 microliters of 50% met-enkephalin solution), or a chronic intramuscular dose (50 microliters of 40% met-enkephalin solution). Rats were sacrificed at 15, 30 and 60 minutes following acute injection. Those on chronic treatment were injected once daily for 10 or 20 days. For the study, we utilized 105 male Wistar rats; 30 comprised the control group, and 75 comprised the study group. The following staining methods were used: 1) succinate dehydrogenase, 2) lactate dehydrogenase, 3) ATPase, 4) acid phosphatase, 5) alkaline phosphatase. We observed marked histoenzymological changes in the rat testis. Particularly noteworthy was a marked change in the energy pathways consisting of a decreased activity of aerobic pathways (decreased SDH activity), increased anaerobic activity (increased LDH activity), and consequently, decreased cellular energy stores (decreased ATPase activity). Similarly, changes were observed in other nonspecific enzymes that led to a fall in acid phosphatase activity and a rise in alkaline phosphatase activity.
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PMID:[Effects of met-enkephalin on the testis. III. Histoenzymatic study]. 253 59

p-Nitrophenyl phosphatase (p-NPP-ase) and inorganic pyrophosphatase (PPi-ase) activities originate from the same alkaline phosphatase enzyme. Only the PPi-ase site has zinc (Zn2+) as a cofactor. Cadmium (Cd2+) in concentrations from 10(-5) mol/l upwards inhibited the PPi-ase activity, but did not inhibit the p-NPP-ase activity at all. In mineralizing tooth germs Cd2+ may replace Zn2+, thereby changing the specific stereoconfiguration in the active centre needed for PPi-ase activity, but not that for p-NPP-ase activity.
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PMID:The effects of cadmium on the p-nitrophenyl phosphatase and inorganic pyrophosphatase activities of alkaline phosphatase in developing hamster tooth germs. 255 86

Recombinant plasmids coding for fusion proteins which consist of human adrenocorticotropin joined to N-terminal sequences of Escherichia coli alkaline phosphatase via collagenase-sensitive linkers were constructed and used for the production of these proteins by transformed E. coli cells. It was shown that repetitive linkers of the form -Gly-(Pro-Xaa-Gly)n-Pro- with n greater than or equal to 2 were cleaved by clostridiopeptidase A (Clostridium histolyticum) by orders of magnitude faster than corresponding nonrepetitive sequences (n = 1). The C-terminal cleavage product was Gly-Pro-adrenocorticotropin which could be converted to the authentic hormone by dipeptidyl peptidase IV. On the basis of these enzymatic reactions a procedure for the preparation of pure adrenocorticotropin was developed. Derivatives of alkaline phosphatase containing similar repetitive linker sequences were cleaved by clostridiopeptidase A as efficiently as the adrenocorticotropin fusion proteins.
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PMID:Production of human adrenocorticotropin by cleavage of alkaline-phosphatase-derived fusion proteins containing repetitive recognition sequences for collagenases. 257 29

An immunoblotting method to detect low-molecular-weight peptides with monoclonal antibodies that normally fail to demonstrate immunoreactivity using conventional blotting techniques is described. Detection of neurophysin, insulin, calcitonin, vasopressin, and beta-endorphin electroblotted on nitrocellulose membranes was optimized after introducing four modifications into the conventional procedure. These include renaturing the gels after sodium dodecyl sulfate electrophoresis, electroblotting the renatured gels in basic transfer buffer, fixing and/or heating the blots, and using avidin/alkaline phosphatase conjugates for antigen/antibody detection. This technique likely enables the denatured peptides to regain their native conformation and, therefore, restores antigenicity and recognition by highly structural specific monoclonal antibodies. Although the most dramatic improvement with this technique is with monoclonal antibodies, a modest improvement in sensitivity can be obtained when immunoblots are probed with polyclonal antibodies. The high resolution of this system will be useful in probing blots of partial proteolytic digests of proteins with both monoclonal and polyclonal antibodies.
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PMID:Detection of low-molecular-weight polypeptides on nitrocellulose with monoclonal antibodies. 269 85


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