Changes in intracellular Ca2+ distribution of rat peritoneal mast cells before and after histamine release.
Rat peritoneal mast cells were stained with quin 2, a fluorescent Ca2+ chelator. By means of a fluorescence microscope and real time image processer, it was revealed that the fluorescence derived from the Ca-quin 2 complex was weak in the area occupied by the nucleus and distributed unevenly in the cytoplasm of the resting cells so as to encompass the individual granules. When compound 48/80 or substance P was added in a Ca-free medium, the fluorescence intensity of quin 2 increased markedly all over the cell, suggesting that a large amount of Ca2+ was released from intracellular Ca stores. The increase in the fluorescence intensity produced by compound 48/80 or substance P in a Ca-free medium was inhibited by pretreatment with certain drugs eliciting an increase of c-AMP levels, such as dibutyryl c-AMP and theophylline, or by some anti-allergic drugs providing a membrane stabilizing action.
D000634:Aminoquinolines; D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D000242:Cyclic AMP / Q000032:analysis; D006636:Histamine Release; D066298:In Vitro Techniques; D008297:Male; D008407:Mast Cells / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D051381:Rats; D011919:Rats, Inbred Strains; D013806:Theophylline / Q000494:pharmacology; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology
D000634:Aminoquinolines; D003189:p-Methoxy-N-methylphenethylamine; D003994:Bucladesine; D013806:Theophylline; D000242:Cyclic AMP; C035739:Quin2; D002118:Calcium