  We investigate the effect of noisy channels in a classical information
transfer through a multipartite state which acts as a substrate for the
distributed quantum dense coding protocol between several senders and two
receivers. The situation is qualitatively different from the case with one or
more senders and a single receiver. We obtain an upper bound on the
multipartite capacity which is tightened in case of the covariant noisy
channel. We also establish a relation between the genuine multipartite
entanglement of the shared state and the capacity of distributed dense coding
using that state, both in the noiseless and the noisy scenarios. Specifically,
we find that in the case of multiple senders and two receivers, the
corresponding generalized Greenberger-Horne-Zeilinger states possess higher
dense coding capacities as compared to a significant fraction of pure states
having the same multipartite entanglement.
