  Recent experiments have obtained the melting line of sodium up to pressures
of about 130 GPa, finding that the melting line from the {\em bcc} phase
reaches a maximum at a temperature of {\em c.a.} 1000 K and a pressure of 31
GPa, and at higher pressures the fusion temperature decreases continuously up
to 118 GPa. Here we report results of a study based on first principles
molecular dynamics, clarifying the nature of the maximum and subsequent
decreasing behavior found in the melting line of sodium.
