Insulin and phorbol ester stimulate conductive Na/sup +/ transport through a common pathway

Journal Article · Mon Feb 01 04:00:00 EST 1988 · Proc. Natl. Acad. Sci. U.S.A.; (United States)

DOI:https://doi.org/10.1073/pnas.85.3.963· OSTI ID:6879639

Civan, M M; Peterson-Yantorno, K; O'Brien, T G

Insulin stimulates Na/sup +/ transport across frog skin, toad urinary bladder, and the distal renal nephron. This stimulation reflects an increase in apical membrane Na/sup +/ permeability and a stimulation of the basolateral membrane Na,K-exchange pump. Considerable indirect evidence has suggested that the apical natriferic effect of insulin is mediated by activation of protein kinase C. However, no direct information has been available documenting that insulin and protein kinase C indeed share a common pathway in stimulating Na/sup +/ transport across frog skin. In the present work, the authors have studied the interaction of insulin and phorbol 12-myristate 13-acetate (PMA), a documented activator of protein kinase C. Preincubation of skins with 1,2-dioctanoylglycerol, another activator of protein kinase C, increases baseline Na/sup +/ transport and reduces the subsequent natriferic response to PMA. Preincubation with PMA markedly reduces the subsequent natriferic action of insulin. This effect does not appear to primarily reflect PMA-induced internalization of insulin receptors. The insulin receptors are localized on the basolateral surface of frog skin, but the application of PMA to this surface is much less effective than mucosal treatment in reducing the response to insulin. The current results provide documentation that insulin and protein kinase C share a common pathway in stimulating Na/sup +/ transport across frog skin. The data are consistent with the concept that the natriferic effect of insulin on frog skin is, at least in part, mediated by activation of protein kinase C.

• Research Organization: Univ. of Pennsylvania School of Medicine, Philadelphia (USA)
• OSTI ID: 6879639
• Journal Information: Proc. Natl. Acad. Sci. U.S.A.; (United States), Journal Name: Proc. Natl. Acad. Sci. U.S.A.; (United States) Vol. 85:3; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALI METAL COMPOUNDS
AMPHIBIANS
ANIMALS
AQUATIC ORGANISMS
BIOLOGICAL EFFECTS
BIOLOGICAL PATHWAYS
BODY
CARCINOGENS
CATIONS
CHARGED PARTICLES
ENZYME INDUCTION
ENZYMES
ESTERS
FROGS
GENE REGULATION
HORMONES
INSULIN
IONS
MEMBRANE TRANSPORT
ORGANIC COMPOUNDS
ORGANS
PEPTIDE HORMONES
PERMEABILITY
PHORBOL ESTERS
PHOSPHORUS-GROUP TRANSFERASES
PHOSPHOTRANSFERASES
SKIN
SODIUM COMPOUNDS
TRANSFERASES
VERTEBRATES