RESUMO
By means of local microapplication of GABA, picrotoxin and CGP 52432, different roles of GABAA and GABAB receptors in the geneses of primary and secondary components of evoked potentials in the somatosensory barrel cortex of rats were shown. The authors conclude that the aftereffect rhythmical components of the evoked potentials are caused by the local pacemaker mechanisms based on endogene properties of barrel neurons.
Assuntos
Potenciais Evocados/fisiologia , Neurônios/fisiologia , Receptores de GABA-A/fisiologia , Receptores de GABA-B/fisiologia , Córtex Somatossensorial/fisiologia , Animais , Benzilaminas/administração & dosagem , Potenciais Evocados/efeitos dos fármacos , Feminino , Antagonistas de Receptores de GABA-A/administração & dosagem , Antagonistas de Receptores de GABA-B/administração & dosagem , Masculino , Neurônios/efeitos dos fármacos , Ácidos Fosfínicos/administração & dosagem , Picrotoxina/administração & dosagem , Ratos , Córtex Somatossensorial/efeitos dos fármacos , Vibrissas/inervação , Vibrissas/fisiologia , Ácido gama-Aminobutírico/administração & dosagemRESUMO
AIM: To analyze the efficiency of transplantation of the bone marrow from a HLA-compatible unrelated donor and continued immunosuppressive therapy (IST) in children with aplastic anemia (AA) unresponsive to 2 courses of IST. SUBJECTS AND METHODS: The study enrolled 14 children aged 2-16 years (median 9 years). A control group comprised 26 patients in whom IST was continued. The median interval between the diagnosis of AA and transplantation was 26 months (9-156 months). The conditioning regimen consisted of thoracoabdominal irradiation in a dose of 2 Gy, fludarabin (Flu) 100-150 mg/m2, cyclophosphamide (Cy) 100-200 mg/kg, antithymocyte globulin (ATG) in 11 patients and Flu, Cy, and ATG in 3. A graft-versus-host reaction was prevented with mycophenolate mefetil in all the patients, tacrolimus in 11, and cyclosporin A in 3. Donors were compatible for high-resolution typing of 10/10 and 9/10 alleles in 8 and 6 patients, respectively; the source of a transplant was bone marrow in 13 patients and granulocyte colony-stimulating factor-mobilized peripheral blood precursors in one case. RESULTS: Thirteen patients achieved primary engraftment after single transplantation; one patient did after repeat transplantation. Grades I to II graft-versus-host reaction (GVHR) developed in 9 patients; postengraftment life-threatening infections in 3, extensive chronic GVHR in 2, circumscribed GVHR in 7. All fourteen hemopoietic cell transplant recipients followed for a median 17.5 months (range 1-71 months) were survivors. CONCLUSION: The likelihood of good survival after unrelated transplantations in AA is much higher than that after continued IST: 100% versus 15 +/- 11%.
