A Study of Mast Cells in Autoimmune Nzb/W F₁ Mice: Possible Relationship Between Mast Cells and Increased Vascular Permeability in the Thymus of Nzb/W F₁ MICE

Abstract

We examined the possible relationship between thymic mast cells and increased vascular permeability in the thymus of autoimmune NZBW F₁ mice. Light-microscopic observation of tissue sections showed that non-autoimmune BDF₁ mast cells increased with age. In contrast, autoimmune NZBW F₁ mast cells did not increase in the thymic parenchyma at the age of 9 weeks. However, NZBW F₁ mast cells resumed the age-associated increase from the age of 12 weeks and exceeded the number of BDF₁ mast cells at the age of 30 weeks. Blood histamine levels of 9-week-old NZBW F₁ mice were higher than those of BDF, mice of comparable age. Furthermore, peritoneal mast cells of NZB/W F₁ mice were more sensitive to compound 48/80 than those of BDF₁ mice. Increased blood histamine levels of NZBN F₁ mice seem to be due to the enhanced histamine release from mast cells. These results suggest a possible correlation between the high histamine levels by degranulation of mast cells and increased vascular permeability in the thymus of NZB/W F₁ mice.

Key Words:

• Autoimmune NZBM F
• thymus
• vascular permeability
• mast cells
• histamine