NOS-II is involved in early differentiation of murine cortical, retinal and ES cell-derived neurons-an immunocytochemical and functional approach.
Nitric oxide (NO), a cell-derived highly diffusible and unstable gas is regarded to be involved in inter- and intracellular communication in the nervous system. Based on findings about the expression of the inducible NO synthase (NOS) isoform during development of early mouse olfactory as well as vestibulocochlear receptor neurons, we intended to prove a general role of this isoform for neuronal differentiation. Using immunohistochemical techniques, an exclusive expression of the inducible NOS-II isoform in early post-mitotic neurons of the developing mouse cortex and retina can be detected. In a pharmacological approach using cultures of the mouse cortex as well as embryonic stem cell-derived neural precursor cells, we investigated the functional role of NO on initial neuronal differentiation. Effects of NOS inhibitors and NO donors on the morphological differentiation were correlated with developmentally regulated calcium current densities, focusing on the effects of the specific NOS-II inhibitor GW 274150. Furthermore, involvement of the soluble guanylate cyclase (sGC)/cGMP signaling cascade was pharmacologically investigated. Our data indicate that while a specific block of NOS-II provokes a clear inhibition of neurite outgrowth formation as well as a decrease of calcium current densities, the inverse is true for exogenous NO donation. In line with lacking immunoreactivity for the sGC and cGMP there are only minor effects of compounds manipulating the sGC/cGMP pathway, suggesting the downstream sGC/cGMP pathway not to be essential in these early differentiation steps.
Arnhold
S
S
Department of Anatomy I, University of Cologne, Joseph-Stelzmann Strasse 9, 50931 Köln, Germany. stefan.arnhold@uni-koeln.de
Fassbender
A
A
Klinz
F-J
FJ
Kruttwig
K
K
Löhnig
B
B
Andressen
C
C
Addicks
K
K
D000818:Animals; D002118:Calcium / Q000378:metabolism; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000187:drug effects; D002540:Cerebral Cortex / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development*; D006152:Cyclic GMP / Q000378:metabolism; D004594:Electrophysiology; D004622:Embryo, Mammalian; D007150:Immunohistochemistry; D051379:Mice; D009474:Neurons / Q000201:enzymology*; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D012160:Retina / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development*; D015398:Signal Transduction / Q000187:drug effects; D013440:Sulfides / Q000494:pharmacology
D020030:Nitric Oxide Donors; D013440:Sulfides; C409004:GW 274150; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D006152:Cyclic GMP; D002118:Calcium