Original Paper

Exogenous Nitric Oxide Regulates the Degranulation of Human Basophils and Rat Peritoneal Mast Cells
Motoyasu Iikura, Toshiaki Takaishi, Koichi Hirai, Hirokazu Yamada, Mariko Iida, Takeshi Koshino, Yutaka Morita

Department of Medicine and Physical Therapy, Faculty of Medicine, University of Tokyo, Japan

Address of Corresponding Author

Int Arch Allergy Immunol 1998;115:129-136 (DOI: 10.1159/000023892)

  Key Words

• Basophils
• Histamine
• Mast cells
• N-Acetylcysteine
• Sodium nitroprusside

  Abstract

This study was designed to investigate whether anti-IgE-induced or ionophore A23187-induced histamine release from human basophils is regulated by exogenous nitric oxide (NO), and to assess some similarities between the effect of NO on basophils and that on rat peritoneal mast cells (RPMC). The NO donor, sodium nitroprusside (SNP), inhibited A23187-induced histamine release from crude human basophils and crude RPMC in a dose-dependent fashion. This downregulation was still observed when SNP was washed out just before the cell stimulation, indicating that the effect of SNP was irreversible. The downregulation disappeared in both purified cell populations after the removal of contaminating cells. However, when purified cells were preincubated with SNP in the presence of 5 mM N-acetylcysteine (NAC), increasing the bioavailability of NO, the downregulation was recovered. The presence of NAC significantly augmented the downregulation of SNP on A23187-induced histamine release from both crude cell populations. In contrast, SNP had no effect on anti-IgE-induced histamine release from either crude or purified basophil preparation in the absence of NAC, and SNP plus NAC inhibited anti-IgE-induced histamine release from both cell preparations. The same results were obtained with crude and purified RPMC preparations under the same conditions. These results show that SNP similarly downregulated exocytosis of basophils and RPMC, and acquired the potent effect in the presence of NAC, indicating that exogenous NO plays a part in the regulation of basophil and mast cell activation.

  Author Contacts

Correspondence to: Dr. Toshiaki Takaishi
Department of Medicine and Physical Therapy
Faculty of Medicine, University of Tokyo
7-3-1, Hongo, Bunkyo-ku, Tokyo 113 (Japan)
Fax +81 3 3815 5954

  Article Information

Received: Received: January 13, 1997
Accepted after revision: September 23, 1997
Number of Print Pages : 8
Number of Figures : 6, Number of Tables : 1, Number of References : 34