Biomaterial Database

Re-epithelialization of the rabbit cornea is regulated by opioid growth factor. 1998

I S Zagon, and J W Sassani, and P J McLaughlin

Department of Neuroscience and Anatomy, The Pennsylvania State University, College of Medicine, 500 University Drive, Hershey, PA 17033, USA. iszl@psu.edu

An endogenous opioid peptide, [Met5]-enkephalin, termed opioid growth factor (OGF) is a tonically active, autocrine-produced inhibitory molecule related to developing, neoplastic, renewing and healing tissues. The present investigation was designed to examine the role of OGF on corneal epithelial wound closure in the rabbit under in vitro and in vivo conditions. A 10-mm diameter epithelial defect was made in the center of the rabbit cornea, and the size of the defect, number of specimens with complete re-epithelialization, and rate of wound closure were evaluated using topical fluorescein and morphometric analysis. In organ culture, the influence of a complete opioid receptor blockade by naltrexone (NTX) showed an acceleration in re-epithelialization compared to controls. The action of excessive agonist (OGF) application revealed that exposure of wounded epithelium to OGF delayed wound closure under in vitro conditions, and did so in a receptor-mediated fashion. The modulatory capability of opioids on wound healing in vivo was explored by examining the effects of opioid peptide-receptor disruption using topical application of NTX, and enhanced healing of the abraded rabbit cornea was noted. The presence and location of OGF and the zeta (zeta) receptor in the normal and injured rabbit corneal epithelium were ascertained by immunocytochemistry, and both OGF and the zeta receptor were detected in basal and suprabasal epithelial cells. These results show that an opioid peptide, OGF, plays a direct role in the repair of injury to the corneal epithelium in the rabbit and acts as a receptor-mediated and constitutively expressed inhibitory molecule.

UI	MeSH Term	Description	Entries
D007150	Immunohistochemistry	Histochemical localization of immunoreactive substances using labeled antibodies as reagents.	Immunocytochemistry,Immunogold Techniques,Immunogold-Silver Techniques,Immunohistocytochemistry,Immunolabeling Techniques,Immunogold Technics,Immunogold-Silver Technics,Immunolabeling Technics,Immunogold Silver Technics,Immunogold Silver Techniques,Immunogold Technic,Immunogold Technique,Immunogold-Silver Technic,Immunogold-Silver Technique,Immunolabeling Technic,Immunolabeling Technique,Technic, Immunogold,Technic, Immunogold-Silver,Technic, Immunolabeling,Technics, Immunogold,Technics, Immunogold-Silver,Technics, Immunolabeling,Technique, Immunogold,Technique, Immunogold-Silver,Technique, Immunolabeling,Techniques, Immunogold,Techniques, Immunogold-Silver,Techniques, Immunolabeling
D009271	Naltrexone	Derivative of noroxymorphone that is the N-cyclopropylmethyl congener of NALOXONE. It is a narcotic antagonist that is effective orally, longer lasting and more potent than naloxone, and has been proposed for the treatment of heroin addiction. The FDA has approved naltrexone for the treatment of alcohol dependence.	Antaxone,Celupan,EN-1639A,Nalorex,Naltrexone Hydrochloride,Nemexin,ReVia,Trexan,EN 1639A,EN1639A
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D011957	Receptors, Opioid	Cell membrane proteins that bind opioids and trigger intracellular changes which influence the behavior of cells. The endogenous ligands for opioid receptors in mammals include three families of peptides, the enkephalins, endorphins, and dynorphins. The receptor classes include mu, delta, and kappa receptors. Sigma receptors bind several psychoactive substances, including certain opioids, but their endogenous ligands are not known.	Endorphin Receptors,Enkephalin Receptors,Narcotic Receptors,Opioid Receptors,Receptors, Endorphin,Receptors, Enkephalin,Receptors, Narcotic,Receptors, Opiate,Endorphin Receptor,Enkephalin Receptor,Normorphine Receptors,Opiate Receptor,Opiate Receptors,Opioid Receptor,Receptors, Normorphine,Receptors, beta-Endorphin,beta-Endorphin Receptor,Receptor, Endorphin,Receptor, Enkephalin,Receptor, Opiate,Receptor, Opioid,Receptor, beta-Endorphin,Receptors, beta Endorphin,beta Endorphin Receptor,beta-Endorphin Receptors
D004744	Enkephalin, Methionine	One of the endogenous pentapeptides with morphine-like activity. It differs from LEU-ENKEPHALIN by the amino acid METHIONINE in position 5. Its first four amino acid sequence is identical to the tetrapeptide sequence at the N-terminal of BETA-ENDORPHIN.	Methionine Enkephalin,5-Methionine Enkephalin,Met(5)-Enkephalin,Met-Enkephalin,5 Methionine Enkephalin,Enkephalin, 5-Methionine,Met Enkephalin
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D014945	Wound Healing	Restoration of integrity to traumatized tissue.	Healing, Wound,Healings, Wound,Wound Healings
D019573	Epithelium, Corneal	Stratified squamous epithelium that covers the outer surface of the CORNEA. It is smooth and contains many free nerve endings.	Anterior Corneal Epithelium,Corneal Epithelium,Corneal Epithelium, Anterior,Epithelium, Anterior Corneal
D019793	Fluorescein	A phthalic indicator dye that appears yellow-green in normal tear film and bright green in a more alkaline medium such as the aqueous humor.	Fluorescein Sodium,Sodium Fluorescein,C.I. 45350,Colircusi Fluoresceina,D & C Yellow No. 7,D & C Yellow No. 8,D and C Yellow No. 7,D and C Yellow No. 8,D&C Yellow No. 7,D&C Yellow No. 8,Diofluor,Disodium Fluorescein,Fluor-I-Strip A.T.,Fluorescein Dipotassium Salt,Fluorescein Disodium Salt,Fluorescein Monosodium Salt,Fluorescite,Fluorescéine sodique Faure,Fluorets,Ful-Glo,Funduscein,Minims Fluorescein Sodium,Minims Fluoresceine,Minims Stains,Optifluor Diba,Uranine,Dipotassium Salt, Fluorescein,Disodium Salt, Fluorescein,Fluor I Strip A.T.,Fluorescein Sodium, Minims,Fluorescein, Disodium,Fluorescein, Sodium,Fluoresceina, Colircusi,Fluoresceine, Minims,Ful Glo,Monosodium Salt, Fluorescein,Sodium, Fluorescein