RESUMO
The role of AMPA and NMDA receptors in the shell of the nucleus accumbens in turning behaviour of rats was investigated. Unilateral injection of the AMPA receptor agonist, AMPA (0.25, 0.4, 0.5 and 1 microg), into the shell of the nucleus accumbens dose-dependently produced contraversive pivoting, namely tight head-to-tail turning marked by abnormal hindlimb backward stepping, while injection of AMPA (0.5 microg) into the core produced only a marginal effect. This shell-specific AMPA effect was dose-dependently inhibited by the AMPA receptor antagonist, NBQX (1 and 10 ng), which alone did not produce turning behaviour. The AMPA-induced pivoting was also dose-dependently inhibited by the non-competitive NMDA receptor antagonist, MK-801 (0.1 and 0.5 microg). Neither MK-801 (0.1, 0.5 and 5 microg) nor the NMDA receptor agonist, NMDA (0.5 and 1 microg), injected unilaterally into the shell, produced turning behaviour. Unilateral injection of a mixture of dopamine D(1) (SKF 38393, 5 microg) and D(2) (quinpirole, 10 microg) receptor agonists into the shell has been found to elicit contraversive pivoting. The dopamine D(1)/D(2) receptor antagonist, cis-(Z)-flupentixol (1 and 10 microg), injected into the shell, in doses known to block dopamine D(1)/D(2) receptor-mediated pivoting, also significantly inhibited AMPA (0.5 microg)-induced pivoting. Moreover, both NBQX (1 and 10 ng) and MK-801 (0.1 and 0.5 microg), injected into the shell, significantly inhibited dopamine D(1)/D(2) receptor-mediated pivoting. It is therefore concluded that unilateral stimulation of AMPA receptors in the shell of the nucleus accumbens can elicit contraversive pivoting, and that both AMPA and dopamine D(1)/D(2) receptors play a critical role in shell-specific pivoting in contrast to NMDA receptors that at best play only a modulatory role.
Assuntos
Flupentixol/análogos & derivados , Movimento/fisiologia , Núcleo Accumbens/fisiologia , Receptores de AMPA/fisiologia , Receptores Dopaminérgicos/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Animais , Maleato de Dizocilpina/farmacologia , Agonistas de Dopamina/farmacologia , Antagonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Antagonistas de Aminoácidos Excitatórios/farmacologia , Flupentixol/farmacologia , Injeções Intraventriculares , Masculino , Movimento/efeitos dos fármacos , Núcleo Accumbens/efeitos dos fármacos , Quinoxalinas/farmacologia , Quimpirol/farmacologia , Ratos , Ratos Wistar , Receptores de AMPA/efeitos dos fármacos , Receptores Dopaminérgicos/efeitos dos fármacos , Receptores de Dopamina D1/efeitos dos fármacos , Receptores de Dopamina D1/fisiologia , Receptores de Dopamina D2/efeitos dos fármacos , Receptores de Dopamina D2/fisiologia , Receptores de N-Metil-D-Aspartato/efeitos dos fármacosRESUMO
We describe a female patient with primary Sjögren's syndrome who subsequently developed chronic myelogenous leukemia. The patient received a bone marrow transplant (BMT) from a genotypically HLA-identical brother after pre-transplant preparation with busulfan and cyclophosphamide. Eighteen weeks later, cutaneous and mucosal chronic graft-versus-host disease developed, followed by death 11 months after transplantation. Anti-Ro/SS-A antibodies disappeared within 6 months post-BMT, but antinuclear antibodies remained positive through the post-transplant course.