Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The measurement of the density of the reaction product produced by the histochemical demonstration of cytochrome oxidase activity provides a method for the visual identification of physiologically active enteric neurons. The current study utilized the cytochrome oxidase technique in order to evaluate the metabolic history of neurons in different regions of the bowel and in chemically identified types of neuron. In addition, the effect of drugs or neurotoxins commonly used in the immunocytochemical identification of enteric neuronal phenotypes was also analyzed. Cytochrome oxidase activity was visualized with a blue-black reaction product resulting from the cobalt-intensified oxidation of 3,3'-diaminobenzidine. Peptides or 5-hydroxytryptamine (5-HT) were localized with biotinylated secondary antibodies and alkaline phosphatase-labeled avidin. Bound avidin or endogenous alkaline phosphatase was visualized with a red reaction product in the presence or absence, respectively, of levamisole. Use of measured without interference from a simultaneously demonstrated histo- or immunochemical marker. A multi-peptidergic class of cholinergic submucosal secretomotor neuron containing neuropeptide Y (NPY) and calcitonin gene related peptide (CGRP) immunoreactivities was found to be less metabolically active than the average of all submucosal neurons. In contrast, a non-cholinergic submucosal secretomotor neuron containing dynorphin (which is also known to contain vasoactive intestinal peptide) immunoreactivity was more metabolically active than submucosal neurons that do not contain this peptide. On average, submucosal neurons were more metabolically active than those of the myenteric plexus, and levels of metabolic activity in the myenteric plexus were found to be higher in the duodenum and the cecum than in the jejunum-ileum or colon. Myenteric neurons characterized by CGRP or NPY immunoreactivities or by endogenous alkaline phosphatase activity, were all less metabolically active than the average of all neurons in myenteric ganglia. Colchicine, which stimulates intestinal motility, was observed to increase cytochrome oxidase activity in enteric neurons, suggesting that an effect on the enteric nervous system contributes to its action on the bowel. The neurotoxins, 6-hydroxydopamine and 5,7-dihydroxytryptamine (5,7-DHT) were each found to stimulate neuronal metabolic activity. 5,7-DHT appeared to activate excitatory subtypes of 5-HT receptor since its effects were blocked or mimicked by compounds that act as antagonists or agonists, respectively, at these receptors.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Evaluation of the activity of chemically identified enteric neurons through the histochemical demonstration of cytochrome oxidase. 170 53

The dorsal resting hair of C3H mice at various ages was shaved, thus activating the hair into the anagen stage. New hair growth after shaving was not uniform in the various age groups. Furthermore, an increasing delay in hair regrowth was observed as the mice became older (20, 66, 188, and 312 days). In the biochemical analysis of hair regrowing and nongrowing skins after shaving, activities of ornithine decarboxylase, transglutaminase, and alkaline phosphatase had higher values in the extract of the hair regrowing area compared with that in the nongrowing area. In studying the effects of various physical and chemical treatments on hair growth after shaving, repeated shaving was in itself clearly shown to stimulate hair growth. Amongst all of the treatments that were applied, topical application of TPA was most able to accelerate hair regrowth, followed by UV irradiation and retinoic acid treatment. Suppression of hair regrowth was observed in PUVA, DHT, and estradiol; and complete inhibition was seen in the animals treated with betamethasone valerate. In biochemical studies, a relatively good correlation was observed between the rate of hair regrowth and skin ODC activities after treatment.
 ...
PMID:Regulation mechanisms of hair growth. 614 Jan 29

While androgens have important skeletal effects, the mechanism(s) of androgen action on bone remain unclear. Current osteoblast models to study androgen effects have several limitations, including the presence of heterogeneous cell populations. In this study, we examined the effects of androgens on the proliferation and differentiation of a novel human fetal osteoblastic cell line (hFOB/AR-6) that expresses a mature osteoblast phenotype and a physiological number (approximately 4,000/nucleus) of androgen receptors (AR). Treatment with 5alpha-dihydrotestosterone (5alpha-DHT) inhibited the proliferation of hFOB/AR-6 cells in a dose-dependent fashion, while it had no effect on the proliferation of hFOB cells, which express low levels of AR (<200/nucleus). In hFOB/AR-6 cells, co-treatment with the specific AR antagonist, hydroxyflutamide abolished 5alpha-DHT-induced growth inhibition. Steady-state levels of transforming growth factor-beta1 (TGF-beta1) and TGF-beta-induced early gene (TIEG) mRNA decreased after treatment of hFOB/AR-6 cells with 5alpha-DHT, suggesting a role for the TGF-beta1-TIEG pathway in mediating 5alpha-DHT-induced growth inhibition of hFOB/AR-6 cells. In support of this, co-treatment of hFOB/AR-6 cells with TGF-beta1 (40 pg/ml) reversed the 5alpha-DHT-induced growth inhibition, whereas TGF-beta1 alone at this dose had no effect on hFOB/AR-6 cell proliferation. Furthermore, treatment of hFOB/AR-6 cells with 5alpha-DHT and testosterone (10(-8) M) inhibited basal and 1,25-(OH)2D3-induced alkaline phosphatase (ALP) activity and type I collagen synthesis without affecting osteocalcin production. Thus, in this fetal osteoblast cell line expressing a physiological number of AR, androgens decrease proliferation and the expression of markers associated with osteoblast differentiation. These studies suggest that the potential anabolic effect of androgens on bone may not be mediated at the level of the mature osteoblast.
 ...
PMID:Effects of gonadal and adrenal androgens in a novel androgen-responsive human osteoblastic cell line. 973 58

We have previously demonstrated that mouse skeletal tissue, rat bone as well as rat or human derived bone cells in culture, show a sex-specific response to gonadal steroids in stimulation of the specific activity of the BB isozyme of creatine kinase (CK). This response could be modified by manipulation of the endocrine environment during early postnatal development. Moreover, pretreatment with vitamin D up-regulated the sex-specific responsiveness and sensitivity to gonadal steroids. In the present study we examine the differentiation pattern into osteoblast-like cells using dexamethasone (DEX) and 1,25 dihydroxy vitamin D3 (1,25D) and their effect on the acquisition of responsiveness to gonadal steroids by the differentiated cells. Cultured femoral bone marrow in the presence of DEX or 1,25D or both, were examined for their response to gonadal steroids by measuring the specific activities of alkaline phosphatase (AP) and CK BB. The constitutive level of CK in both male- and female-derived bone cells was decreased by DEX, by 1,25D or by both, whereas the constitutive level of AP was increased by DEX while decreased by 1,25D or by both. Following incubation of the bone marrow cultures with DEX, treatment with estradiol 17beta (E2, 30 nM, 24 h) stimulated CK activity in female derived bone cells, with no effect of treatment with dihydrotestosterone (DHT, 300 nM). In contrast, in male derived bone cells, DHT but not E2 increased CK activity. This sex-specific response was also achieved upon culturing with 1,25D and was significantly augmented by culturing with both. No response to gonadal steroids was seen with undifferentiated bone marrow cells. All cultures responded to IGF-I when cultured with or without DEX and/or 1,25D but with no augmentation by 1,25D. Gonadal steroids increased AP to a much lesser extent; but enzyme activity decreased in the presence of 1,25D. IGF-I stimulated AP slightly with no effect of 1,25D. These findings suggest that manipulation of the hormonal milieu in early stages of differentiation sequence of osteoblast-like cells, determines the subsequent selective responsiveness of the developing bone tissue to gonadal steroids.
 ...
PMID:Differentiation of cultured mice bone marrow into osteoblast-like cells results in acquisition of sex-specific responsiveness to gonadal steroids. 1550 84