犬の皮膚ならびに関節嚢のHistamine含量と肥満細胞のSinomenineによる変化とその回復

Abstract

After intravenous injection of 3 mg/kg sinomenine into the dog, the reduction in the histamine contents in the skin (ear margin, perivulvar region, lip and back skin) and in joint capsules (shoulder, hip and knee joints) as well as the manner of its recovery later on were studied. In parallel with this study their morphological changes were observed by counting the number of mast cells in the skin (lip and back skin) and in joint capsules (shoulder and hip joints).For the duration of the period between five hours and five days after the sinomenine injection the contents of the skin histamine in the ear margin and back were reduced to about 40 per cent of the normal values while that in the lip and perivulvar regions down to about 20 per cent. The histamine contents in the joint capsules five hours afterwards down to about 10 per cent the normal level. The recovery of histamine contents in the skin thereafter was extremely slow, returning to 90 per cent of the normal level in the back skin and only 50-60 per cent in the skin of ear margin, genital area and lip 40 days after the injection. However, the recovery of the histamine values in joint capsules was much more rapid than that in the skin, returning to 80 per cent the normal already 10 days afterwards.The mast cell counts both in the skin and joint capsules reached the minimum during the period between five hours and five days after the injection: in the back skin it was about 40 per cent the normal; in the lip skin about 20 per cent; and in the capsules of shoulder and hip joints down to 20 per cent, and thereafter the recovery in the skin was slower than that in joint capsules.The proportion of disrupted mast cells was greatest in the specimen prepared five hours after the injection, and in the skin and joint capsules about 90 per cent of the total was disrupted; but by the fifth day almost no disrupted cells could be observed. As for the morphology of the disruption, the swelling, degranulation, the extrusion or scattering of granules outside the cell could be observed, and these granules show metachromasia as their characteristic. In joint capsules, especially near the surface of the synovial membrane, a marked change could be recognized.Cells appearing at an early stage of recovery were generally smaller than normal ones, and had comparatively narrow cytoplasma as compared with the large nucleus, filled with metachromatic granules; and they appeared near small vessels in loose connective tissues. Besides these, the shrinking of degranulated cells and the picture what might be thought to be granules refilling such cells could be observable. In joint capsules a new formation of mast cells was marked in deeper connective tissues, and these cells appeared earlier than in the case of the skin.That the way how the reduction of histamine contents by histamine releasers occurs and the way how its recovery takes place in the skin and joint capsules show numerically a parallel relationship with the degree of changes of tissue mast cells and their repair indicates that mast cells are the main storage of hisfamine in these tissues.