Liedtke CM, Cole T. Antisense oligodeoxynucleotide to PKC-delta blocks alpha 1-adrenergic activation of Na-K-2Cl cotransport.
THE AMERICAN JOURNAL OF PHYSIOLOGY 1997;
273:C1632-40. [PMID:
9374649 DOI:
10.1152/ajpcell.1997.273.5.c1632]
[Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A role for protein kinase C (PKC)-delta and -zeta isotypes in alpha 1-adrenergic regulation of human tracheal epithelial Na-K-2Cl cotransport was studied with the use of isotype-specific PKC inhibitors and antisense oligodeoxy-nucleotides to PKC-delta or -zeta mRNA. Rottlerin, a PKC-delta inhibitor, blocked 72% of basolateral-to-apical, bumetanide-sensitive 36Cl flux in nystatin-permeabilized cell monolayers stimulated with methoxamine, an alpha 1-adrenergic agonist, with a 50% inhibitory concentration of 2.3 microM. Methoxamine increased PKC activity in cytosol and a particulate fraction; the response was insensitive to PKC-alpha and -beta II isotype-specific inhibitors, but was blocked by general PKC inhibitors and rottlerin. Rottlerin also inhibited methoxamine-induced PKC activity in immune complexes of PKC-delta, but not PKC-zeta. At the subcellular level, methoxamine selectively elevated cytosolic PKC-delta activity and particulate PKC-zeta activity. Pretreatment of cell monolayers with antisense oligodeoxynucleotide to PKC-delta for 48 h reduced the amount of whole cell and cytosolic PKC-delta, diminished whole cell and cytosolic PKC-delta activity, and blocked methoxamine-stimulated Na-K-2Cl cotransport. Sense oligodeoxynucleotide to PKC-delta and antisense oligodeoxynucleotide to PKC-zeta did not alter methoxamine-induced cotransport activity. These results demonstrate the selective activation of Na-K-2Cl cotransport by cytosolic PKC-delta.
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