GABA receptor plasticity in lymphocytes

DIONISIO L,; ARIAS, V; DE ROSA MJ; BOUZAT C; ESANDI MDEL C

Huerta Grande, Córdoba

Congreso; II Reunión Conjunta de Neurociencias; 2010

Sociedad Argentina de Investigación en Neurociencias y Taller Argentino de Neurociencias

GABA receptor plasticity in lymphocytes Dionisio L., Arias V, De Rosa MJ, Bouzat C and Esandi MC Laboratorio de Neurofisiología y Farmacología Molecular – INIBIBB – Bahía Blanca ldionisio@criba.edu.ar   The plasticity of GABA receptors has been studied in the nervous system. Neurons can modify the number and composition of their receptors in response to different stimuli, such as exposure to GABA and nicotine. We have reported that human lymphocytes express a functional neuronal-like GABAergic system which inhibits lymphocyte proliferation. In this work we aimed to determine if this non-neuronal system also shows plasticity. To this end, we studied changes in the expression level of subunits of ionotropic GABA receptors from Jurkat cells, a human T-leukemic cell line. By RT-PCR, we determined that these cells express α1, β3, δ, γ2 and ρ2 subunits. To study plasticity, we incubated the cells with 100 µM GABA or 10 µM nicotine for different time periods. While the expression level of α1 subunit increases after 15 hs, it decreases after 40 hs of incubation with these drugs. The high level of expression at 15 h-incubation is also evidenced by the detection of GABA-elicited currents in 35% of the tested cells. In contrast, currents cannot be detected from cells incubated during 40 hs with GABA. We conclude that lymphocyte GABA receptors show plasticity as neuronal receptors; and this plasticity may play a role in the modulation of immune response.