The effect of cAMP signaling on the longitudinal extension of spinal sensory neurons in the chicken embryo.
Developing sensory axons grow into the spinal cord in a three-step process: the axons extend toward and into the cord, then branch rostrally and caudally to establish a longitudinal pathway, and finally grow into the grey matter. This study investigated regulation by cAMP of the longitudinal extension of this pathway within the spinal cord. The cAMP pathway was pharmacologically altered in chicken embryos to determine its effects on the establishment of the longitudinal extension of the dorsal funiculus. A forskolin-induced increase in cAMP in ovo inhibited longitudinal growth by sensory afferents. Furthermore, blocking cAMP activation of protein kinase A (PKA) in ovo with H-89 substantially increased longitudinal extension. These results demonstrate a specific role for the cAMP/PKA pathway in the initial longitudinal spinal afferent growth in the chicken embryo.
Coutinho-Budd
Jaeda C
JC
Department of Anatomy and Neurobiology, University of Vermont College of Medicine, Burlington, Vermont, USA.
Ezerman
Elizabeth B
EB
Forehand
Cynthia J
CJ
D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D001369:Axons / Q000502:physiology; D002642:Chick Embryo; D000242:Cyclic AMP / Q000037:antagonists & inhibitors / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D007546:Isoquinolines / Q000494:pharmacology; D009475:Neurons, Afferent / Q000502:physiology*; D011984:Sensory Receptor Cells / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D013116:Spinal Cord / Q000196:embryology*; D013449:Sulfonamides / Q000494:pharmacology
D007546:Isoquinolines; D013449:Sulfonamides; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide