Use get(fig_no,'children') to identify all of the items on the fig, inlcuding the axes
Use get(axis_no,'children') to identify the various plots etc.,
Use get(plot_no) to get the full list of parameters of each plot, and for the actual plots, you should see a field called "YData", once you've ID'd each plot,
set(plot_no,'YData',1000*get(plot_no,'YData'))
