In vivo control of NMDA receptor transcript level in motoneurons by viral transduction of a short antisense gene

Glutamate receptors play critical roles in normal and pathological processe s. We developed an antisense gene delivery strategy to modulate the NMDA ty pe of glutamate receptor, Using transient transfection in vitro and viral m ediated gene transfer in vitro and in vivo, the effect of expression of an antisense gene fragment (60 bp) of the NR1 subunit was tested. Immunoblot a nalysis showed an antisense-concentration-dependent reduction in the NR1 su bunit upon transient co-transfection of a plasmid expressing a sense NR1 ge ne and a plasmid expressing the antisense fragment into COS-7 cells. After recombination into an adenoviral vector, this antisense fragment reduced th e amount of endogenous NR1 protein in PC12 cells. Finally, direct intrapare nchymal injection of the viral vector into rat spinal cord resulted in dimi nished NR1 in motor neurons. Our results demonstrate the efficacy of this a pproach, which combines antisense with viral gene delivery to control the e xpression of specific genes in vivo. This approach may also be useful in re ducing excitatory neurotransmission in vivo, with implications for the trea tment of spinal disorders such as amyotrophic lateral sclerosis or chronic pain. (C) 2001 Published by Elsevier Science B.V.