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Updated: Sep 28, 2026

Methodology for Biomimetic Chemical Neuromodulation of Rat Retinas with the Neurotransmitter Glutamate In Vitro
Published on: December 19, 2017
Adenosine A1 receptor agonist treatment up-regulates rat brain metabotropic glutamate receptors
J L Albasanz1, D León, M A Ruíz
1Area de Bioquímica, Departamento de Química Inorgánica, Orgánica y Bioquímica, Facultad de Ciencias Químicas, Centro Regional de Investigaciones Biomédicas, Universidad de Castilla-La Mancha, Avenida Camilo José Cela 10, 13071, Ciudad Real, Spain.
Abstract:
Chronic R-N(6)-phenylisopropiladenosine (R-PIA) subcutaneous injection for 6 days significantly increased total glutamate receptor number (180% of control) in rat brain synaptic plasma membranes (SPM), without affecting receptor affinity. A higher increase in metabotropic glutamate (mGlu) receptor number (258% of control) was also detected, indicating that mGlu is the main type of glutamate receptor affected by this treatment. On the other hand, the observed increase in basal and calcium- and Gpp(NH)p-stimulated phospholipase C (PLC) activity after treatment was associated with a significant increase in PLC beta(1) isoform, detected in SPM by immunoblotting assays. Moreover, an increase in PLC activity stimulation with trans-ACPD, in the absence and in the presence of Gpp(NH)p, was detected after R-PIA treatment. These results show that mGlu receptors and its effector system, PLC activity, are up-regulated by chronic exposure to an adenosine A(1) receptor agonist and suggest the existence of a cross-talk mechanism between both signal transduction pathways in rat brain.
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