The Astronomical Observatories of Trieste and Padova are involved in the Grid.it project aiming at ’Enabling platforms for high-performance computational grids orientated to scalable virtual organizations’. In this framework we explore the use of grid technologies for developing astrophysical applications. The testbed for grid applications is the Italian INFN Production Grid for Scientific Applications based on the LCG-2 (LHC Computing Grid, Robertson 2001) distribution, which is the evolution of the software produced by the European DataGrid project. Within Grid.it, the OAPd group focused on the portability to the Grid of an existing system for the consultation of large astronomical catalogues, currently serving on the net the Second Guide Star Catalog (GSC-II) (Benfante et al. 2000), while the Astronomical Observatory of Trieste (OATs) is dealing with the similar problem of integrating in the Grid the archive of observational data from the Italian Galileo National Telescope (TNG) (Smareglia et al. 2003) and, as a further step, to provide processing for the data retrieved through gridenabled pipelines. Since in the grid infrastructure based on LCG an adequate model for DBMSes is not available, INFN and INAF institutes are collaborating to design and implement an architecture to integrate DBMSes in the existing