Using grand-canonical quantum Monte-Carlo (QMC) simulations combined w
ith maximum entropy (MaxEnt) analytic continuation, as well as analyti
cal methods, we examine the one- and two-particle dynamical properties
of the Hubbard model on two coupled chains at small doping. For large
values of the interchain coupling t(perpendicular to) greater than or
similar to 2t the local rung approximation (LRA) developed for the ha
lf-filled case describes the high-energy features of the system. In ad
dition, in the bonding charge channel a pronounced gapless mode is obs
erved, which indicates the insulator-metal transition. The main featur
es of the quasi-particle dispersion are found unchanged (''rigid-band
like'') when going to smaller (isotropic) couplings and intermediate d
opings.