Focal deletion of the adenosine A1 receptor in adult mice using an adeno-associated viral vector.
Adenosine is a ubiquitous neuromodulator that increases sleep, inhibits seizures, and promotes neuroprotection. Many of these effects are mediated by A1 receptors, but A1 receptors are expressed in most brain regions, and distinguishing the precise site of action of adenosine is challenging. To test the role of adenosine in different hippocampal regions, we have used the Cre-loxP system and an adeno-associated viral (AAV) vector to focally delete endogenous adenosine A1 receptors in the hippocampus. Microinjection of an AAV vector containing the gene for Cre recombinase induced intense, focal, neuron-specific recombination in reporter mice. In a separate line of mice with loxP sites flanking the major coding exon for the adenosine A1 receptor, this AAV-Cre markedly reduced A1 receptor mRNA and focally abolished the postsynaptic response to adenosine without any change in basic electrophysiologic properties. Adenosine inhibits signaling between CA3 and CA1 neurons, but it is unclear from pharmacologic studies whether this response is caused by presynaptic or postsynaptic effects. Deletion of A1 receptors from CA3 neurons abolished this response to adenosine, but deletion of A1 receptors from CA1 neurons had no effect, demonstrating a presynaptic site of action. This transduction knock-out technique holds enormous potential for dissecting the functions of different CNS pathways.
Scammell
Thomas E
TE
Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA.
Arrigoni
Elda
E
Thompson
Margaret A
MA
Ronan
Patrick J
PJ
Saper
Clifford B
CB
Greene
Robert W
RW
D000241:Adenosine / Q000378:metabolism; D000818:Animals; D000229:Dependovirus / Q000235:genetics; D004594:Electrophysiology; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology; D017930:Genes, Reporter; D005822:Genetic Vectors / Q000008:administration & dosage; D049452:Green Fluorescent Proteins; D006624:Hippocampus / Q000378:metabolism*; D066298:In Vitro Techniques; D019426:Integrases; D008164:Luminescent Proteins / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008845:Microinjections; D009474:Neurons / Q000378:metabolism; D018408:Patch-Clamp Techniques; D018047:Receptors, Purinergic P1 / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D011995:Recombination, Genetic; D014764:Viral Proteins; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics
D008164:Luminescent Proteins; D018047:Receptors, Purinergic P1; D014764:Viral Proteins; D049452:Green Fluorescent Proteins; C045073:Cre recombinase; D019426:Integrases; D001616:beta-Galactosidase; D000241:Adenosine