Adenosine enhances nerve growth factor (NGF)-induced neurite outgrowth in PC12 cells. We found that adenosine increases NGF-induced phosphorylation of extracellular signal-regulated kinase (ERK), but decreases the duration of phosphorylation of p38 mitogen-activated protein (MAP) kinase. Therefore, we further examined the involvement of protein phosphatase in these effects of adenosine. FK506, ...

The involvement of the adhesion molecules L1, N-CAM, and J1 in adhesion and neurite outgrowth in the peripheral nervous system was investigated. We prepared Schwann cells and fibroblasts (from sciatic nerves) and neurons (from dorsal root ganglia) from 1-d mice. These cells were allowed to interact with each other in a short-term adhesion assay. We also measured outgrowth of dorsal root ganglio...

A number of the benzodiazepines (BZDs) inhibit nerve growth factor (NGF)-induced neurite outgrowth in a dose-dependent manner in PC12 cell cultures. The rank order of potency of a series of BZDs for inhibition of neurite outgrowth does not correlate with the order of their affinity constants for the so-called peripheral BZD sites present on PC12 cells. Whereas the inhibition of neurite extensio...

The Deleted in Colorectal Cancer (DCC) gene is a candidate tumor suppressor gene that is predicted to encode a transmembrane polypeptide with strong similarity to the neural cell adhesion molecule (N-CAM) family. Previous studies have suggested that several different N-CAMs, when expressed in non-neuronal cell types can stimulate neurite outgrowth from PC12 rat pheochromocytoma cells. Based on ...

Although recovery following a stroke is limited, undamaged neurons under the right conditions can establish new connections and take on-board lost functions. Sonic hedgehog (Shh) signaling is integral for developmental axon growth, but its role after injury has not been fully examined. To investigate the effects of Shh on neuronal sprouting after injury, we used an in vitro model of glial scar,...

Our work centers on understanding how the extracellular matrix molecule tenascin-C regulates neuronal growth. We have found that the region of tenascin-C containing only alternately spliced fibronectin type-III repeat D, called fnD, when used by itself, dramatically increases neurite outgrowth in culture. We used overlapping synthetic peptides to localize the neurite outgrowth-promoting site wi...

Neurons, with their long axons and elaborate dendritic arbour, establish the complex circuitry that is essential for the proper functioning of the nervous system. Whereas a catalogue of structural, molecular, and functional differences between axons and dendrites is accumulating, the mechanisms involved in early events of neuronal differentiation, such as neurite initiation and elongation, are ...

Previous studies have demonstrated that the divalent cation manganese (Mn) causes PC12 cells to form neurites in the absence of NGF. Since divalent cations modulate the binding affinity and specificity of integrins, and integrin function affects neurite outgrowth, we tested the hypothesis that Mn induces neurite outgrowth through an integrin-dependent signaling pathway. Our studies support this...

Previous studies have shown that neuroblastoma cells and several types of primary neuronal cells in culture rapidly extend neurites when switched from serum-containing to serum-free medium. The present studies on cloned neuroblastoma cells show that thrombin blocked this spontaneous differentiation at 2 nM with a half-maximal potency of 50 pM. This required the catalytic activity of thrombin an...

A method for clamping cytosolic free Ca 2+ ([Ca2+]~) in cultures of rat sympathetic neurons at or below resting levels for several days was devised to determine whether Ca 2+ signals are required for neurite outgrowth from neurons that depend on Nerve Growth Factor (NGF) for their growth and survival. To control [Ca2+]i, normal Ca 2+ influx was eliminated by titration of extracellular Ca 2+ wit...