A Role of Cyclic AMP in a Neurotrophic Process

TROPHIC effects of neurones can be defined as long-term interactions between nerve cells and the tissues they innervate, which initiate or control molecular modifications in the target cells¹. An example of trophic activity is the maintenance of the motor end plate of skeletal muscle by the nerve fibre. The motor nerve appears to exert a morphogenetic effect on its formation, because both the structural specializations and Cholinesterase activity of the end plate develop only in relation to the nerve fibre^2–5. Conversely, denervation is followed usually by degeneration of the junction and loss of end plate Cholinesterase activity^6–8.