Morphological changes in immune and endocrine organs of mice injected with a gonadotropin-releasing hormone analog

Chronic stress induces structural alterations in splenic lymphoid tissue that are associated with changes in corticosterone levels in wistar-kyoto rats

Major depressive disorder patients present chronic stress and decreased immunity. The Wistar-Kyoto rat (WKY) is a strain in which the hypothalamic-pituitary-adrenal axis is overactivated. To determine whether chronic stress induces changes in corticosterone levels and splenic lymphoid tissue, 9-week-old male rats were subject to restraint stress (3 h daily), chemical stress (hydrocortisone treatment, 50 mg/Kg weight), mixed stress (restraint plus hydrocortisone), or control treatment (without stress) for 1, 4, and 7 weeks. The serum corticosterone levels by RIA and spleens morphology were analyzed. Corticosterone levels as did the structure, size of the follicles and morphology of the parenchyma (increase in red pulp) in the spleen, varied depending on time and type of stressor. These changes indicate that chronic stress alters the immune response in the spleen in WKY rats by inducing morphological changes, explaining in part the impaired immunity that develops in organisms that are exposed to chronic stress.

The immune enhancement of sodium lauryl sulfoacetate in chickens

The purpose of this study is to investigate feasibility of sodium lauryl sulfoacetate (SLS) as an immunoadjuvant in chickens. After treating with 62.5, 125, 250, or 500 mug/mL SLS in vitro, lymphocyte proliferation assay of chicken peripheral blood mononuclear cells showed that the OD(570) values of all experimental groups, as well as Con A-stimulated group, were significantly higher than that of the untreated control group. After injection with 1.0, 2.0, or 4.0 mg/kg of SLS for 3 consecutive days, chickens were vaccinated with an attenuated vaccine against Newcastle disease virus (NDV), and the immunoadjuvant effects of SLS were evaluated on the basis of immune organ index, antibody response, and CD(4) (+)/CD(8) (+) T-cell ratio. The results confirmed that SLS could enhance NDV-specific antibody response and increase CD(4) (+)/CD(8) (+) T-cell ratio in vivo. Furthermore, SLS could improve NDV-specific antibody response in thiamphenicol-treated chickens. These data indicate that SLS not only can improve humoral immune response but also reverse the immunosuppressive effect of thiamphenicol in chickens.

Morphological changes in immune and endocrine organs of stressed mice after administration of a gonadotropin-releasing hormone analogue

Administration of Surfagon, a gonadotropin-releasing hormone analogue, in doses of 0.1 and 5.0 microg/kg before emotional nociceptive stress increased lymphocyte migration from the thymus, decreased the volume of lymphoid tissue in the spleen and thymus, reduced the width of the zona fasciculata and increased the width of the zona glomerulosa in the adrenal cortex of male CBA mice. These effects of the peptide persisted in castrated animals. Surfagon prevented stress-induced activation of the adrenal glands and accidental transformation of the thymus and spleen in castrated animals.