  The luminosities and velocity dispersions of the extinction-corrected Balmer
emission lines of giant HII regions in nearby galaxies exhibit a tight
correlation (~0.35 dex scatter). There are few constraints, however, on whether
giant HII regions at significant lookback times follow an L-sigma relation,
given the angular resolution and sensitivity required to study them
individually. We measure the luminosities and velocity dispersions of H-alpha
and H-beta emission from 11 HII regions in Sp1149, a spiral galaxy at redshift
z=1.49 multiply imaged by the MACS J1149 galaxy cluster. Sp1149 is also the
host galaxy of the first-known strongly lensed supernova with resolved images,
SN Refsdal. We employ archival Keck-I OSIRIS observations, and newly acquired
Keck-I MOSFIRE and Large Binocular Telescope LUCI long-slit spectra of Sp1149.
When we use the GLAFIC simply parameterized lens model, we find that the
H-alpha luminosities of the HII regions at z=1.49 are a factor of 6.4+2.9-2.0
brighter than predicted by the low-redshift L-sigma relation we measure from
Very Large Telescope MUSE spectroscopy. If the lens model is accurate, then the
HII regions in Sp1149 differ from their low-redshift counterparts. We identify
an HII region in Sp1149 that is dramatically brighter (by 2.03+-0.44 dex) than
our low-redshift L-sigma relation predicts given its low velocity dispersion.
Finally, the HII regions in Sp1149 are consistent, perhaps surprisingly, with
the z=0 star-forming locus on the Baldwin-Phillips-Terlevich diagram.
