Effect in neonatal thymectomy on experimental autoimmune thyroiditis in guinea pigs.

These studies examined the effect of neonatal thymectomy on the induction of experimental autoimmune thyroiditis (EAT) in the guinea pigs. Thymectomy was found to result in a consistent and profound inhibition of the development of lesions of EAT in both strain 2 and strain 13 guinea pigs. Thymectomized guinea pigs also had reduced antibody titers to guinea pig thyroglobulin (GPTG), while delayed hypersensitivity reactions to GPTG were less markedly affected by thymectomy. Thymectomized guinea pigs had significant functional peripheral T cells as evidenced by normal responses of lymph node cells to T cell mitogens. These results indicate that a T cell subpopulation which is sensitive to neonatal thymectomy is required for the development of EAT and antithyroglobulin antibody in the guinea pig.     

Suppression of experimental autoimmune thyroiditis in guinea pigs by pretreatment with thyroglobulin-coupled spleen cells

Pretreatment of Strain 2 and Strain 13 guinea pigs with guinea pig thyroglobulin (GPTG) coupled to syngeneic spleen cells (GPTG-SC) suppressed the development of experimental autoimmune thyroiditis (EAT) induced by immunization with GPTG in complete Freund's adjuvant (CFA). Antibody titers to GPTG were only minimally suppressed in GPTG-SC pretreated animals. GPTG-SC also suppressed the sensitization of periotneal exudate T lymphocytes which proliferate in vitro in the presence of GPTG.     

Lipids and caplain in guinea pig tissues in the process of development of experimental autoimmune encephalomyelitis

The character of some lipids level change--cholesterol and phospholipids--as basic lipid components of cell membranes in the guinea-pig brain and liver tissue, and in serum in conditions of development of experimental autoimmune encephalomyelitis (EAE) have been investigated on the 11th, 21st, 27th day after inoculation. It has been detected, that the level of the investigated lipids changes wavely and indifferent-direction in the brain tissue on the 21st day of EAE. Similar variability observed in the activity of proteolytic ferment calpain, which is authentically reduced in the brain tissue by the 11th hour and increases up to the test objective level in the subsequent periods of EAE development. In the liver the level of alpha-tocopherol is reduced, while the content of studied lipids does not change. The investigated parameters can be attributed to the factors, which play an essential role in structural stability of cell membranes and their variability in conditions of EAE development is related to the processes of nervous cells demyelinisation and, hence to occurrence of such pathology as multiple sclerosis in people.     

Hypothermia tolerance in guinea pigs with experimental myasthenia gravis

Hypothermia tolerance was studied in guinea pigs with experimental myasthenia gravis induced by immunization with homologous thymus extract and Freund's complete adjuvant. Untreated guinea pigs and guinea pigs immunized with liver extract and Freund's complete adjuvant served as controls. Thymus-immunized guinea pigs survived to a significantly lower temperature at asystole than did the liver-immunized controls. This finding is consistent with a slight diminution in temperature maintenance mechanisms in guinea pigs with experimental autoimmune thymitis. The observed increase in hypothermia tolerance may be due to impaired shivering as a consequence of the partial neuromuscular block demonstrable in the myasthenia gravislike state.