Intranuclear microtubules in lung mast cells of guinea pigs in anaphylactic shock.

Intranuclear microtubules were found in lung mast cells during anaphylactic shock following ovalbumin challenge of guinea pigs passively sensitized with homocytotropic antibodies. Simultaneously, such cells showed mitochondrial swelling with a clear matrix and partially disrupted cristae. Although a decreased number of mast cell granules generally accompanied these observations, the degree of degranulation and the morphologic appearance of the granules are less reliable criteria to indicate the immediate participation of a cell in the anaphylactic phenomenon. The cells that presented intranuclear microtubules were mainly found in the vicinity of the bronchiolar smooth muscle. The distribution of cations has been investigated in these tissues with a combined oxalate-pyroantimonate method. Whereas in controls the reaction product is located mainly in the nucleus and the mitochondria of mast cells, these sites become almost completely devoid of precipitate during the anaphylactic reaction. A hypothetical link between histamine release, intracellular distribution of cations, possibly calcium, and the appearance of intranuclear microtubules in mast cells is proposed.