Nitric oxide and cyclic GMP are involved in angiotensin II AT(2) receptor effects on neurite outgrowth in NG108-15 cells.
In their undifferentiated state, NG108-15 cells express only the angiotensin II (Ang II) type 2 receptor (AT(2)). We have previously shown that Ang II induced neurite outgrowth of NG108-15 cells, a process involving sustained activation of p42/p44(mapk) activity. We have also shown that Ang II stimulates nitric oxide (NO) production. The aim of the present study was to investigate the role of the NO/cyclic GMP (cGMP) cascade in the signal transduction of the AT(2) receptor-stimulated neurite outgrowth. Three-day treatment of cells with dbcGMP induced neurite outgrowth as did Ang II. Preincubation with an inhibitor of cGMP-dependent protein kinase, KT5823, resulted in the formation of short neurites, while in the presence of LY83583 or methylene blue, two inhibitors of guanylyl cyclase, cells resembled control cells with only one or two thin processes. Western blot analyses indicated that nNOS was present in NG108-15 cells. Immunoprecipitation with antiphosphotyrosine antibodies showed that Ang II induced NOS activity and increased cGMP production through a Gi-dependent pathway. However, neither L-NAME, KT5823, nor LY83583 affected the activation of p42/p44(mapk) induced by Ang II, indicating that the pathway NO/guanylyl cyclase/cGMP was not involved in Ang II-induced activation of MAPK. The present results suggest that the neurite outgrowth induced by Ang II results from at least parallel but complementary pathways, one involved in neurite elongation (through the cooperation of MAPK and PKG) and the other involved in sprouting (through cGMP).
Gendron
Louis
L
Service of Endocrinology, Faculty of Medicine, University of Sherbrooke, Quebec, Canada.
Côté
Frédéric
F
Payet
Marcel D
MD
Gallo-Payet
Nicole
N
D000470:Alkaloids / Q000494:pharmacology; D000634:Aminoquinolines / Q000494:pharmacology; D000818:Animals; D002227:Carbazoles; D002454:Cell Differentiation / Q000502:physiology; D006152:Cyclic GMP / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006162:Guanylate Cyclase; D007211:Indoles; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D016501:Neurites / Q000502:physiology*; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000378:metabolism; D052248:Nitric Oxide Synthase Type I; D010766:Phosphorylation; D044139:Receptor, Angiotensin, Type 2; D011945:Receptors, Angiotensin / Q000378:metabolism*; D018160:Receptors, Cytoplasmic and Nuclear / Q000037:antagonists & inhibitors / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D000071756:Soluble Guanylyl Cyclase; D014407:Tumor Cells, Cultured
D000470:Alkaloids; D000634:Aminoquinolines; D002227:Carbazoles; D004791:Enzyme Inhibitors; D007211:Indoles; D020030:Nitric Oxide Donors; D044139:Receptor, Angiotensin, Type 2; D011945:Receptors, Angiotensin; D018160:Receptors, Cytoplasmic and Nuclear; C073601:KT 5823; D009569:Nitric Oxide; C041715:6-anilino-5,8-quinolinedione; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D006162:Guanylate Cyclase; D000071756:Soluble Guanylyl Cyclase; D006152:Cyclic GMP; D019331:NG-Nitroarginine Methyl Ester