Relative Weight Of Lymphoid Organs Research Articles

Self-stimulation behavior: Consequences upon immunity?

A variety of behaviorial and emotional factors can affect the immune response by changing the brain immunoregulatory mechanisms, resulting in immunosuppression or immunopotentiation. This experiment deals with the effect of chronic self-stimulation behavior on the immune response and lymphoid tissue. Male rats were stereotaxically implanted with bipolar electrodes into the lateral hypothalamus and 7 days after surgery were screened for self-stimulation behavior. Lateral hypothalamus self-stimulating rats (LH-SS) were allowed to self-stimulate for 60 min/day for a period of 9 consecutive days: 5 days before and 4 days after immunization with 5 × 10 9 sheep red blood cells (SRBC). The animals were sacrificed and plaque-forming cell assay (PFC), microhaemmagglutination reaction with SRBC, and differential blood leucocyte counts were performed. The thymus, spleen, and inguinal lymph nodes were weighed and processed for histological examination. In the LH-SS group, an enhanced PFC response and increased anti-SRBC antibody titer were observed when compared to controls. The thymus and spleen of LH-SS rats were smaller in size in comparison with controls, but only with moderate changes in splenic cellular make-up. The relative number of lymphocytes was increased in peripheral blood of LH-SS rats when compared to intact animals. The results obtained suggest that chronic self-stimulation behavior can modulate some parameters of humoral immune response and affect the relative weight of lymphoid organs in the rat.

Electro-acupuncture modifies humoral immune response in the rat.

The immunomodulating properties of "Shangqiu" (LP-5), "Ququan" (H-8), and "Rangu" (R-2) points were studied in several experiments performed on male Wister rats treated bilaterally by acupuncture (A) or electro-acupuncture (EA). On the stimulation day 3, the sheep-red-blood cells (SRBC) antigen was injected intraperitoneally and four days later, the immunological tests (plaque forming cells-PFC, direct microhemagglutination) were performed. Also, the relative weights of lymphoid organs (spleen and thymus) and adrenal gland were derived after sacrifice. The results obtained suggest pronounced immunomodulating properties of 200 Hz cathodal current stimulation at H-8 point. The immunosuppression observed reflected in a decreased number of PFC and reduced relative weights of adrenal gland revealed in all A- or EA-treated groups.

Indications of Immunodepression in Chickens Infected with Various Strains of Marek's Disease Virus

The effect of infection by various strains of Marek's disease virus (MDV) on the immune function of 3-week-old chickens was examined. MDV strains of low (CU-2, RB-7) and high (RB-3, MD-5, and MD-11) pathogenicity were compared with prototype JM-10 strain of moderate pathogenicity. Mortality, whole body weight, relative weights of lymphoid organs, histopathology, humoral antibody responses to thymus-dependent and -independent antigens, and in vitro lymphocyte responses to mitogen stimulation were investigated at 1, 2, and 3 weeks postinfection. MDV strains of high pathogenicity significantly depressed responses at 3 weeks postinfection, seeming to indicate the ability of these viruses to induce severe immunodepression. However, the fact that the moderately pathogenic and even some of the low-pathogenicity strains induced immunodepression suggests that other viral mechanisms are also important in its determination.

Effect of 2,5-hexanediol on immunocompetence of mice

A preliminary study on immunotoxicologic evaluation of 2,5-hexanediol (one of the principal metabolites of n-hexane), involving multiple immunological parameters, was carried out in mice. Mice were exposed to 2,5-hexanediol at a 1 5 LD 50 dose level for 7 days. Pathotoxicological changes such as marked reduction in absolute and relative lymphoid organ weights, histological abnormalities in thymus, spleen, and adrenal, and reduction in cellularity of lymphoid organs were found. Immune function tests such as delayed hypersensitivity reactions, plaque-forming cell assays, serum antibody titer against SRBC, and resistance to endotoxin shock were also markedly impaired. Results obtained in this study showed that 2,5-hexanediol causes impairment to immunocompetence in mice.