Decrease in peritoneal mast cell count in rats with adjuvant arthritis. I. Time course and interstrain difference

Abstract

Adjuvant was injected into the left hind paw of Sprague-Dawley (SD) and Wistar rats. In SD rats a marked decrease in the mast-cell count and histamine content of the peritoneal fluid and a significant increase in the histamine content as well as the mast-cell count in the mesentery appeared between 1 and 2 weeks after adjuvant injection. This period approximately coincided with that of the development of secondary inflammatory lesions such as polyarthritis. The adjuvant-induced changes in the peritoneal fluid were more marked in SD than in Wistar rats, corresponding to more intense adjuvant arthritis in the SD strain. In Wistar rats a tendency towards an increase in the histamine content of the mesentery was observed from 2 weeks after adjuvant injection. Adjuvant injection did not have any significant effect on the histamine content of the caecum or the skin of either strain. These results show that adjuvant causes a redistribution of mast cells between the peritoneal fluid and the tissues surrounding the peritoneal cavity probably as a result of delayed hypersensitivity.

Decrease in peritoneal mast cell count in rats with adjuvant arthritis. II. inhibition by anti-inflammatory and immunosuppressive drugs

“…According to the procedures described in the previous paper [1], an adjuvant mixture was prepared and 0.05 ml of the mixture was injected intradermally under the volar surface of the left hind paw of rats. The paw volume was measured with a mercury plethysmograph coupled to a pressure transducer as described previously [12].…”

“…The paw volume was measured with a mercury plethysmograph coupled to a pressure transducer as described previously [12]. The experimental procedures for peritoneal mast cells were the same as described in the previous report [1]. The experimental procedures for peritoneal mast cells were the same as described in the previous report [1].…”

“…In the previous report [1], it was shown that the decrease in the mast-cell count in the peritoneal fluid of adjuvant-induced arthritic rats is probably due to the redistribution of these cells between the peritoneal cavity and the tissues surrounding it. This phenomenon appears roughly coincident with the development of secondary inflammatory lesions such as polyarthritis.…”