  We carried out $^{12}$CO(J = 1 -0) observations toward bar and arm regions of
strongly barred galaxies, NGC 1300 and NGC 5383, with the Nobeyama 45-m radio
telescope (beamsize of 1-2 kpc in the galaxies). The aim of the observations is
to qualitatively examine a new scenario for the suppression of star formation
in bars based on recent high-resolution numerical simulations: higher speed
collisions between molecular clouds in the bar region compared with the arm
region suppress the massive star formation. CO emissions were detected from all
the regions, indicating the presence of the molecular gases in the strong bars
without associating clear HII regions. In both galaxies, the velocity width of
the CO line profile tends to be larger in the bar region than in the arm
region, which is qualitatively consistent with the new scenario.
