glycogen and Eye-Injuries

This study assesses the impact of various forms of injury on matrix degrading enzymes in nutritionally compromised rat corneas. In vitamin A-deficient (nutritionally compromised) and normal control corneas, in vivo or ex vivo mild mechanical abrasion did not appreciably alter the activity of either the 65-kDa or the 92-kDa gelatinases. In contrast, after thermal injury, while no appreciable change was detected in activity associated with the 65-kDa gelatinase in either vitamin A-deficient or normal control corneas, 92-kDa gelatinolytic activity was consistently higher in corneas from both groups, although activity associated with nutritionally compromised corneas was much higher. In these corneas, thermal injury also induced the expression of two high molecular weight (approximately 130-kDa and 225-kDa) gelatinases and a 27-kDa caseinase. While gelatinases were totally inactivated by inhibitors of metalloproteinases such as 1,10-phenanthroline and Galardin MPI, the 27-kDa caseinase showed considerable susceptibility to a mixture of serine protease inhibitors (aprotinin, dichloro-isocoumarin and pA-PMSF [(4-amidino-phenyl)-methane-sulphonyl fluoride]. Furthermore, unactivated-lymphoreticular cells from either nutritionally compromised or normal control animals contained a 24- and 27-kDa caseinase, however most of the activity was due to the 24-kDa caseinase. In contrast, glycogen-activated lymphoreticular cells contained a preponderance of the 27-kDa caseinase. Activated-lymphoreticular cells also expressed 92-kDa, 130-kDa and 225-kDa gelatinases. The presence of low molecular weight caseinases in lymphoreticular cells implicates them as the source of these enzymes.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Cornea; Corneal Injuries; Corneal Ulcer; Eye Injuries; Gelatinases; Glycogen; Male; Metalloendopeptidases; Peptide Hydrolases; Rats; Rats, Sprague-Dawley; Reticulocytes; Vitamin A Deficiency

The corneal epithelial cell has a unique sliding capability. The epithelial cell spreads and migrates in an amebic fashion without mitotic activity when the continuity of the epithelium is broken. This movement is demonstrated both in vivo and in vitro. Prompt sliding for sealing the wound defect is apparently the first step of the wound healing of the superficial cornea. Cut edges of collagen fibers show no sign of activity towards healing the wound. The energy source of the sliding is provided mainly from stored glycogen in the epithelial cells. Sliding is inhibited by removal of glycogen from the cell or by adding glycolytic enzyme inhibitors.

Topics: Animals; Cell Membrane; Cell Movement; Cornea; Corneal Injuries; Desmosomes; Endoplasmic Reticulum; Epithelial Cells; Epithelium; Eye Injuries; Glycogen; Golgi Apparatus; Intercellular Junctions; Iodobenzoates; L-Lactate Dehydrogenase; Mercuribenzoates; Mitosis; Rabbits; Ribosomes; Wound Healing

Glycogen, adenosine triphosphate, and hydration were measured in rabbit corneal epithelium to determine whether the corneal epithelium glycogen decrease, increase in epithelial hydration, and decrease in epithelial adenosine triphosphate stores, seen as a result of contact lens wear, were secondary only to anoxia or may also have resulted from mild trauma, with no interference to oxygenation. Conventional contact lens wear, trauma, and oxygen-permeable contact lens wear caused metabolic changes, showing trauma as well as anoxia may play an important role in the corneal epithelial response to contact lens wear.

Topics: Adenosine Diphosphate; Adenosine Triphosphate; Animals; Contact Lenses; Contact Lenses, Hydrophilic; Cornea; Epithelium; Eye Injuries; Glucosephosphate Dehydrogenase; Glycogen; Hexokinase; Hypoxia; L-Lactate Dehydrogenase; Methylmethacrylates; Permeability; Pyruvate Kinase; Rabbits; Silicones; Water-Electrolyte Balance

Topics: Animals; Cattle; Cornea; Corneal Injuries; Eye Burns; Eye Diseases; Eye Injuries; Glycogen; Graft vs Host Reaction; Histocytochemistry; Inflammation; Microscopy, Electron; Neutrophils; Phagocytosis; Rabbits; Rats

Topics: Asthma; Cell Nucleus; Colitis, Ulcerative; Eosinophils; Eye Injuries; Glycogen; Hepatitis; Humans; Leukemia; Leukocytes; Lung Diseases; Schistosomiasis; Skin Window Technique

Topics: Animals; Cornea; Cortisone; Eye Injuries; Glycogen; Glycosaminoglycans; Guinea Pigs; Haplorhini; Leukocytes; Pharmacology; Polysaccharides; Rabbits; Research; Wound Healing; Wounds, Penetrating