RESUMO
The sizes of lymphocyte populations in lymphoid organs of nicotinic acetylcholine receptor knockout and chimera (knockout/wild-type) mice were studied by flow cytometry. The absence of beta2 subunit decreased, while nicotine treatment increased B lymphocyte numbers in the bone marrow. In chimera mice, either beta2 or alpha7 subunits influenced lymphocyte populations in primary lymphoid organs, while in the spleen, only alpha7 receptors were critical. More annexin V-positive B cells were found in the bone marrow of knockout than wild-type animals. We conclude that nicotinic receptors are involved in regulating lymphocyte development and control the B lymphocyte survival.
Assuntos
Processos de Crescimento Celular/fisiologia , Linfócitos/fisiologia , Receptores Nicotínicos/fisiologia , Animais , Antígenos CD/metabolismo , Comportamento Animal , Transplante de Medula Óssea/métodos , Contagem de Células/métodos , Citometria de Fluxo/métodos , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Linfócitos/classificação , Masculino , Camundongos , Camundongos Knockout , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Quimera por Radiação/fisiologia , Receptores Nicotínicos/deficiência , Baço/metabolismo , Baço/efeitos da radiação , Fator Tímico Circulante/metabolismo , Fator Tímico Circulante/efeitos da radiação , Receptor Nicotínico de Acetilcolina alfa7RESUMO
Irradiation of the epithelial cells from human thymus (cell line HTSC) by arsenid-gallium laser (0.89 nm, 1500 Hz) induces an enhancement of thymic hormone production. The concentration of alpha-1-thymosin was substantially increased on the days 1 and 5 in culture after irradiation. The increase of thymulin level in cultural supernatants was less pronounced and displayed after irradiation during 3-4 minutes. Local laser irradiation of thymus region of rats (5 minutes, 10 times) induce the increase of serum concentration of alpha-1-thymosin and the decrease of serum level of thymulin 2 days after irradiation.
Assuntos
Lasers , Hormônios do Timo/efeitos da radiação , Animais , Linhagem Celular , Células Cultivadas , Epitélio/metabolismo , Epitélio/efeitos da radiação , Raios gama , Humanos , Ratos , Timalfasina , Fator Tímico Circulante/análise , Fator Tímico Circulante/efeitos da radiação , Timosina/análogos & derivados , Timosina/sangue , Timosina/efeitos da radiação , Hormônios do Timo/biossíntese , Fatores de TempoRESUMO
Whole-body exposure of rats to X-rays (4, 6 and 8 Gy) and neutron radiation (1, 1.5 and 2 Gy) causes a dose-dependent inhibition of endocrine function of thymus and death of its lymphoid cells. Shielding of thymus somewhat reduces the degree and duration of inhibition of thymus hormone secretion.