Purpose. Creatine kinase (CK) is an important enzyme in intracellular energy supply, with different isoforms exhibiting tissue- and organelle-specific localization We studied the presence and distribution of 3 different CK isoforms in the human retina and RPE. Methods. Eight eyes enucleated for various disease processes (age range 2 to 86 years) were investigated by immunohistochemistry. Formalin-fixed paraffin sections were stained using isoform-specific CK antibodies: CK-M (muscle type, monoclonal), CK-B (brain type, polyclonal), and sMt-CK (mitochondria! type, polyclonal). Immunoreactivity (IR) was tested using the ABC method, and results were visualized with AEC. Results. In all specimens, IR was detected in retina and RPE with the 3 different antibodies used. Anti-CK-B reacted most intensely while staining with anti-CK-M was very weak. The staining pattern among the different isoforms appeared similar but varied depending on the age and the disease process of the tissue examined. In general, labeling was most consistent in the RPE, the outer plexiform layer (where it was most prominent at the area of the synaptic terminals) and to a lesser degree in the inner retina. Photoreceptors (mostly inner segments) and nerve fibers were immunoreactive in "healthy" retina while only little IR was observed in glaucomatous retina. With anti-sMt-CK, a distinct, punctate or linear staining pattern was observed at the basal aspect of RPE, most likely corresponding to basally localized mitochondria. Conclusions CK is present in human retina and RPE, the most prominent isoform being CK-B. The pattern of immunoreactivity appears to reflect disease processes, indicating that CK plays an important role in the energy dynamics of ocular tissues.
|Original language||English (US)|
|Journal||Investigative Ophthalmology and Visual Science|
|State||Published - Dec 1 1997|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience