Role of Toxic Factors in Anaphylactic Shock of Rats. II.

On the Role of Histamine Release and Mast Cell Damage in Rat Anaphylaxis

“…Especially M o t a (13,14) has compiled considerable evidence that histamine might be im plicated in rats actively sensitized with horse scrum and HPV and based on the following: (1) A rise in plasma histamine concentra tion, (2) tissue mast cells are disrupted during anaphylaxis, (3) rats are partly protected against anaphylaxis by antihistamine or by pretreatment with the chemical histamine liberator, compound 48/80. Other workers, however, although establishing a rise in plasma histamine or other evidence of its release in rat anaphyl axis as well, reached the conclusion that histamine does not play an important role in producing the symptoms in the rat (4,5,6,23). These discrepancies may in part be due to difference in the mode of sensitization and the type of HPV used.…”

“…A series of investigations dealing with conditions for histamine release and for mast cell damage by antigen in the intact rat or isolated rat tissues or isolated rat mast cells have been presented (1,5,6,12,13,14,19,20,21,24). Comparison of results of these studies reveals considerable discrepancies.…”

“…However, the question of basic importance whether or not this process is of primary order, is not uniformely answered by different workers (3,4,5,6,13,16,22,23). Some have observed a close re lationship between the severity of shock symptoms and the amount of histamine released during rat anaphylaxis (13,14), others strong ly oppose such a view (4,5,6,23). Recently, we observed a striking difference in the behaviour of rat mast cells in the course of ana phylaxis in vivo and in vitro.…”

“…Since intravenous injection of the antigen into actively sensitized rats causes shock only during the first period of time, i. e. when 'mast cell sensitizing' antibody is detectable in the circulating blood, this could be taken to support the conception that mast cells and the agents contained in them might play an important role in rat anaphylaxis. In fact, a great number of studies have reached the conclusion that histamine is released and mast cells do become severely damaged in the course of active anaphylaxis in vivo in the rat (3,4,5,6,13,14). However, the question of basic importance whether or not this process is of primary order, is not uniformely answered by different workers (3,4,5,6,13,16,22,23).…”

“…In fact, a great number of studies have reached the conclusion that histamine is released and mast cells do become severely damaged in the course of active anaphylaxis in vivo in the rat (3,4,5,6,13,14). However, the question of basic importance whether or not this process is of primary order, is not uniformely answered by different workers (3,4,5,6,13,16,22,23). Some have observed a close re lationship between the severity of shock symptoms and the amount of histamine released during rat anaphylaxis (13,14), others strong ly oppose such a view (4,5,6,23).…”