Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A microcellular dispersion procedure for the rat neurohypophysis was developed, comprising tissue softening and dissociation using a special sieving sytringe. In preparatory studies the influence of mesh width, and treatment with trypsin, pronase or collagenase-hyaluronidase was investigated using light and electron microscopy, as well as with microchemistry by means of protein and lactate dehydrogenase activity determinations. Trypsinization gave the best results. In the final adopted procedure, 3 incubated neurohypophyses were sequentially sieved through a 200- and a 50-mum mesh. The resulting 50-mul dispersion was found to contain numerous ultrastructurally well-preserved pinched-off axonal endings (neurosecretosomes), and pituicytes often revealing processes. On the basis of DNA and oxytocin assays 11% of the pituicytes and 28% of the axonal cytoplasm were recovered. Oxytocin immunofluorescence microscopy showed hormone within the neurosecretosomes, but often also in the cytoplasm of pituicytes. Microdensity gradient centrifugation was performed on neurohypophyseal disperions, in order to obtain fractions enriched for neurosecretosomes and pituicytes. Fractions were characterized by means of phase contrast, oxytocin immunofluorescence and electron microscopy, as well as by oxytocin and DNA assays as respective markers. With a 10:14:22% (w/v) Ficoll gradient, fractions were obtained for which the relative purification was by a factor of 4 on the basis of DNA/oxytocin ratios.
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PMID:Enzymic preparation of neurosecretosome- and pituicyte-enriched fractions from the rat neurohypophysis. 18 63

The innervation of the salivary gland of the cockroach Nauphoeta cinerea (Olivier) has been investigated with the use of light and scanning electron microscopy. Light microscopy of methylene blue stained glands reveals the presence of a dual innervation arising from the ventral nerve cord and the stomodeal nervous system; the principal innervation is that from the ventral nerve cord which passes to the gland via the reservoir ducts. Branches of these nerves form a plexus on the acinar surface, the axons of which exhibit swelling at irregular intervals. The presence of this surface plexus and the axonal swellings was confirmed by scanning electron microscopy both in normal glands and in those in which the basal lamina had been removed by means of an HCl-collagenase digestion method. No acinar plexus was seen to be formed by branches of the stomatogastric nerve that were associated with the gland. However, other branches of this nerve were clearly connected with a complex network of multipolar neurones on the surfaces of the anterior regions of both salivary reservoirs.
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PMID:The salivary glands of the cockroach Nauphoeta cinerea (Olivier). A study of its innervation by light and scanning electron microscopy. 63 91

The aim of this study was to describe the normal distribution of calcitonin gene-related peptide (CGRP) and substance P (SP) containing fibres in the knee joint of the mouse and to obtain insight into the changes in innervation associated with degenerative processes in the joint. Arthrosis was induced by a single subpatellar intra-articular injection of bacterial collagenase. After decalcification in EDTA solutions, the CGRP and SP fibres were visualized by peroxidase-antiperoxidase pre-embedding immunocytochemistry for light microscopy. Control experiments on the mouse brain as a reference for the effect of EDTA on the immunostaining showed that the decalcification procedure with EDTA had not impaired the immunostaining. A rich innervation of thin varicose CGRP and SP immunoreactive fibres was found in most peri- and intra-articular tissue components. The periosteum, synovial tissues, the joint capsule and the intra-articular fat tissues were richly innervated. Less intense innervations were also found in the subchondral bone plates of the tibio-femoral joint and of the patella. Fibres were also found in the soft tissues between the patellar tendon and the femoral groove. No differences could be found between the location of CGRP and SP fibres with respect to the localization in the joint, but generally more CGRP fibres were found. The collagenase-induced osteoarthrosis was characterized by sclerosis of the subchondral bone, patellar dislocation, osteophyte formation, synovial proliferation and by severe cartilage abrasion, particularly on the medial side of the femoro-tibial joint. The overall distribution of CGRP and SP fibres was the same as in the control joints. However, major differences were found in all studied joints at specific locations around the cruciate ligaments, in the synovium around the patella, in the soft tissues lateral of the patella and in plica tissue between the patella and femoral groove. The CGRP and SP innervation was no longer detectable by immunolabelling with the antibodies. With a polyclonal antibody to the growth associated protein GAP-43/B-50, signs of degenerated axonal profiles were observed in these locations. At other peripheral locations, such as the muscles, the GAP-43/B-50 distribution was normal. In conclusion, the present study provides detailed information on the localization of CGRP and SP fibres, which may be involved in pain perception. Knowledge of the changes that occur during arthrosis may give more insight into the clinical symptoms.
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PMID:Calcitonin gene-related peptide, substance P and GAP-43/B-50 immunoreactivity in the normal and arthrotic knee joint of the mouse. 128 63

Methods for the study of axons involve whole nerve preparations, teased preparations of axons that are excised from their proximal and distal connections, and tissue culture models. As a complement to these, it would be advantageous to study separated, isolated axons in vivo, still in continuity with the end organ distally and the spinal cord central nervous system neuron proximally. This would allow the study of axon function, normal or pathological, in a close relationship to its biological environment. To achieve this, we have passed the surgically isolated sciatic nerve of a rat through a chamber specially designed for enzymatic dissociation. This was based on principles derived from a prior in vitro method for dissociating nerve into axons. The chamber has controlled temperature and flow and is on an inverted microscope stage, allowing observation of the process. We perfused the chamber with a calcium-free solution followed by a series of enzymes: collagenase, trypsin, and hyaluronidase. This dissociates that part of the extracellular matrix external to the Schwann cells, leaving free, myelinated axons with their Schwann cells. In this acute preparation, the axons continue to conduct action potentials for at least 8 hours. Furthermore, an in vitro study of the axon after the in vivo dissociation demonstrated that axonal transport was maintained in over 90% of the axons, directly visualized on an AVEC-DIC type of microscope system. Properties of axonal transport or active spike propagation can thus be studied individually in an in vivo axon preparation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Model for the study of individual mammalian axons in vivo, with anatomical continuity and function maintained. 241 87

Certain parts of the peripheral nervous system were observed by a modification of the KOH-collagenase method by Miller et al. (1982). The sciatic nerve of the mouse, and dorsal root ganglion, lingual muscle and jejunum of the rat were fixed over one day at room temperature in a fixative containing paraformaldehyde and glutaraldehyde. After fixation, specimens were treated with 5N KOH solution for 5-10 min at 60 degrees C, immersed in a collagenase solution for 3-5 h at 37 degrees C and processed for scanning electron microscopy (SEM). In adequately treated specimens, connective tissue matrices and basal laminae were completely removed without causing any severe tissue damage. The three-dimensional visualization of cellular elements of peripheral nerves was enabled with the following results: 1) Individual nerve fibers of the sciatic nerve were clearly exposed. Myelinated fibers were non-branching cords with local annular constrictions at the node of Ranvier, while unmyelinated ones branched and anastomosed with one another to form loose networks. The sites of accumulation of the Schwann cell cytoplasm swelled on the surface of the myelinated fibers. Mesaxons were visualized as longitudinal furrows. 2) Ganglion cells covered by satellite cells were observed in the dorsal root ganglion. The ganglion cells were covered by their own convoluted dendro-axonal processes, thus forming the initial glomeruli of Cajal. Satellite cells at the glomeruli extended many finger-like projections surrounding the dendro-axonal processes. 3) Motor endplates were observed in lingual muscles. Terminal Schwann cells (teloglia) at the endplate were clearly visualized: the round perikaryon extended cytoplasmic processes along the axonal branches within the endplate. The processes issued fine finger-like projections from their margins. 4) Vascular autonomic plexuses were clearly demonstrated in lingual muscles. Unmyelinated nerves branched and anastomosed to form elaborate nerve networks around the vessels. Neuronal processes and associated Schwann cells were identifiable at high magnification. 5) Submucous nerve plexuses in the jejunum consisted of numbers of ganglia and interconnecting strands of fibers which formed very complicated networks. These observations indicate that this modified KOH-digestion method is useful for the SEM study of the three-dimensional cellular organization of nervous elements in various tissues.
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PMID:A modified KOH-collagenase method applied to scanning electron microscopic observations of peripheral nerves. 284 21

Chromaffin cells from the monkey adrenal medulla were maintained in vitro in the presence of nerve growth factor (NGF) and the neuronal properties of these cells were assessed. Single-cell preparations were obtained by collagenase-trypsin treatment of the minced adrenal medulla tissue. Cells assumed a glandular to epithelioid morphology after twenty-four hours of culture. Twelve percent of these cells were shown to extend neurites spontaneously after five days. NGF-stimulated neuritic outgrowth from most cells after five days of culture and these neurites remained for at least three weeks. Cells exhibited intense histofluorescence for catecholamines even after three weeks in vitro in the presence of NGF and positive staining for tyrosine hydroxylase and dopamine beta hydroxylase could be detected by immunocytochemistry. Moreover, the chromaffin cells were shown to bind tetanus toxin, which is a specific marker for neurons. Tetanus toxin labelling was not dependent upon the presence of neurites on these cells. Transmission electron microscopy indicated that cultured cells contained numerous dense-core vesicles similar to non-cultured medulla cells. Many of the neurites possessed the morphological features of axons; long varicose processes resembling noradrenergic fibers were identified by catecholamine histofluorescence and tyrosine hydroxylase immunocytochemistry. Microtubular arrays, in an axonal-like organization pattern, were seen ultrastructurally along with the presence of many dense-core vesicles. These data support the potential of adult primate chromaffin cells as a source of sympathetic neuronal tissue for neural transplantation.
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PMID:Neuronal properties of monkey adrenal medulla in vitro. 287 Aug 11

This investigation was undertaken to clarify the three dimensional ultrastructure of the subependymal layer in relation with the ependymal cell layer in rat brain using the scanning electron microscope (SEM). The subependymal layer existing below the ependyma of the third ventricle in the brain of mature albino rats was examined with S E M. The hypothalamus freshly excised after median sagittal section was treated by collagenase with or without trypsin for a short while to remove the ependymal cells at the ventricular wall. After the enzymatic pretreatment of the specimen, many ependymal cells were removed and the subependymal layer was partially exposed. Most of the ciliated ependymal cells remaining at the ventricular wall extended long, single basal processes which then penetrated into the subependymal layer. The subependymal layer was composed of a delicate framework of thin processes of glial cells, ependymal cells and, in addition nerve cells. Scattered among the neuropil just beneath the ependymal cell layer, there were relatively small, globular subependymal cells. Occasionally, there were large bundles of unmyelinated nerve fibres in the subependymal layer. The individual nerve fibres distinctly showed many axonal varicosities within the fibres. Intermingled with the nerve fibres, glial processes of various forms were present. The structure of the ependymal cells and the subependymal layer was compared with the findings already reported in the studies using light and transmission electron microscope.
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PMID:Scanning electron microscopic observations of the ependymal cell and the subependymal layer of the third brain ventricle in the rat. 297 95

The ninth and tenth abdominal sympathetic ganglia of bullfrogs were studied by light microscopy and transmission and scanning electron microscopy after the removal of the connective tissue elements overlying the neurons. Digestion of tissues with trypsin and subsequent acid hydrolysis exposed the unipolar neurons, which remained covered by their satellite cells. The preganglionic innervation was visible on the proximal segment and axon hillock region of the postganglionic neurite. Clusters of small cells seen at the periphery of ganglia probably corresponded to groups of cells with abundant catecholamine-containing granules (SIF cells). Digestion with collagenase and protease removed some or all of the satellite cells in addition to the connective tissue. The true neuronal surfaces had short finger-like processes, whereas the external surfaces of satellite cells were smooth. Preganglionic nerve varicosities were clearly visible on the proximal segment of the postganglionic neurite, on the axon hillock and on the cell body of neurons. A few axonal varicosities were fractured to reveal the synaptic vesicles within. The possible effects of the distribution and glial ensheathment of nerve varicosities on their function are discussed.
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PMID:Scanning electron microscopic studies of bullfrog sympathetic neurons exposed by enzymatic removal of connective tissue elements and satellite cells. 301 3

1. A study has been made of the ionic currents in voltage-clamped single rabbit nodes of Ranvier at 22-26 degrees C both under normal conditions, and after the nerve fibres had been acutely demyelinated by a variety of treatments designed to lossen the myelin from the axonal membrane. 2. The myelin-loosening treatments included application of various combinations of: lysolecithin (to dissolve the myelin); collagenase (to loosen the connective tissue in the nodal region); high-potassium Locke solution, hypertonic and hypotonic solutions (to induce axonal volume changes). 3. At a critical stage in such treatment (usually after 15-45 min) a large outward current suddenly appeared. 4. There was no substantial change in the size of the measured inward sodium current when measured at this critical stage. 5. The outward current was blocked by internal TEA and caesium ions, had a reversal potential that became more positive when the external potassium concentration was increased, was kinetically similar to the known potassium current in frog fibres, and was therefore assumed to be a potassium current. 6. The phase of large outward current, whenever it appeared, was always accompanied by the appearance of a slow transient capacitative component in the leakage current, which indicated a marked increase in the effective nodal capacity (of 10- to 60-fold). We suggest that the slow transient capacity current reflected charging of newly exposed axonal membrane, probably in the paranodal region, which was uncovered by the various acute demyelination treatments. This internodal membrane seems to contain mostly potassium channels and few, if any, sodium channels. 7. Newly dissected fibres occasionally showed large potassium currents before treatment, particularly if they were deliberately stretched during dissection; a marked slow capacity transient current was consistently present in these fibres. 8. The effects of acute paranodal demyelination on the sodium and potassium currents, and on the transient capacity currents, can be simulated by a model in which the node is coupled to a cable-like paranode which contains Hodgkin--Huxley type potassium channels and which has a much higher leakage resistance. 9. The functional significance of the presence of potassium channels in rhe internodal region (at least in the paranode) of mammalian fibres is discussed.
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PMID:Evidence for the presence of potassium channels in the paranodal region of acutely demyelinated mammalian single nerve fibres. 626 73

In the mouse, arthritis was induced by a single sub-patellar intraarticular injection of bacterial collagenase. This procedure induces also patellar malalignment. A rich innervation of thin varicose calcitonin gene-related peptide (CGRP) and substance P (SP) immunoreactive fibers was found in the joint capsule, in the periosteum of the patella, in the synovial tissues at the lateral border of the patella, in the femoral groove, and in the subchondral bone of the patella and femur. Moreover, fibers were found in plica tissues between the quadriceps and patellar tendon, and the femoral groove. After the collagenase treatment, the general innervation pattern was comparable to that of the controls, but CGRP and SP innervation was no longer detectable with the antibodies in the plica tissues, and was to a lesser extent detectable in the fat pad of the patella, in the lateral borders of the patella and in the proliferated synovial tissues. Signs of degenerated axonal profiles were observed in these locations with a polyclonal antibody to the growth-associated protein GAP-43/B-50. At all the other peripheral locations, such as the muscles, the GAP-43/B-50 distribution was normal.
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PMID:Innervation of the patella. An immunohistochemical study in mice. 751 3


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