Expression of Protein Kinase C Isotypes in the Albino Guniea Pig Cochlea / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Protein kinase plays an important role in transmembrane signalling, which is modulated by cellular transduction by second messengers such as inositol-1, 4, 5-triphosphate (IP3), Diacylglycerol (DG), cAMP, to express biological activity by stimulation of hormones, neurotransmitters, antigens, growth factors. Protein kinase Cs participate in signal transduction of cell, secretion of neurotransmitter, regulation of ion conduction, exocytosis, gene expression and cellular proliferation. Also, it raises slow motility by Na+-H+ exchange (NHE) and Ca2+ channel in the outer hair cells. It may also be involved in mechanical transduction, cellular proliferation and reproduction in supporting cells, and in producing endolymphs using the KCNE1 and Na+/K+-ATPase in the lateral wall of cochlea. MATERIALS AND METHOD: We investigated the immunoreactivities of the PKC (alpha, beta, gamma, delta) via paraffin section and surface preparation of the cochlea of albino guinea pigs. RESULTS: PKC alpha immunoreactivities were shown in the outer and inner hair cell cytoplasm and delta was revealed in the type II fibrocytes and suprastrial cells in the basal turn of the spiral ligament. But beta, gamma were not shown. CONCLUSION: We suggest that PKC alpha may induce the slow motility and depolarization to mediate the ion conductance in the hair cells. Also, PKC delta may participate in the production of endolymph. We thus conclude that PKC alpha and delta play an important role in the cochlear signal transduction.