Brownian motion and Bessel process

Question

Can you help me with the following: Prove that a geometric Brownian motion can be represented as a time-changed Bessel process $$ \exp(B_t+vt)=R_{A_t} $$ where $A_t= \int_{0}^t \exp(2(B_s+vs)) ds$ and $(R_t)$ is a Bessel process of parameter $2v+1$.