PMID- 8698394
OWN - NLM
STAT- MEDLINE
DCOM- 19960905
LR  - 20190512
IS  - 0019-2805 (Print)
IS  - 1365-2567 (Electronic)
IS  - 0019-2805 (Linking)
VI  - 87
IP  - 2
DP  - 1996 Feb
TI  - Role of intracellular calcium as a priming signal for the induction of nitric 
      oxide synthesis in murine peritoneal macrophages.
PG  - 296-302
AB  - Because the role of intracellular Ca2+ in the two-signal process for the 
      induction of nitric oxide (NO) synthesis is controversial, this study was 
      undertaken to examine the role of Ca2+ in the transcriptional regulation of 
      inducible NO synthase (iNOS) in murine peritoneal macrophages. Treatment of the 
      cells with thapsigargin (TG) or 2,5-di-(t-butyl)-1,4-benzodihydroquinone 
      (tBuBHQ), which are the specific and potent Ca(2+)-ATPase inhibitors of 
      endoplasmic reticulum (ER), showed modest effects on tumoricidal function, 
      whereas TG or tBuBHQ in combination with interferon-gamma (IFN-gamma) or 
      lipopolysaccharide (LPS) showed marked effects on tumoricidal function of the 
      cells. The tumoricidal effects of the activated macrophages were correlated with 
      the amount of NO synthesis, and totally abrogated by the use of NOS inhibitor, 
      NG-monomethyl-L-arginine (NGMMA). The increases in NO synthesis was reflected as 
      increased amounts of iNOS mRNA by Northern blotting. To confirm that iNOS 
      induction was due to the changes in the intracellular Ca2+ level, the 
      acetoxymethyl ester of 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid 
      (BAPTA-AM), an intracellular Ca2+ chelator, was used. Blocking the increase of 
      cytosolic free Ca2+ significantly decreased the induction of NO synthesis. To 
      demonstrate that intracellular Ca2+ acts as a 'priming' signal rather than a 
      'triggering' signal on the induction of NO synthesis by murine peritoneal 
      macrophages, we designed several experiments. When the cells were treated with TG 
      6 hr after the treatment with IFN-gamma, there was no increase in NO synthesis. 
      In addition, when the cells were treated with TG or LPS 6 hr after treatment with 
      tBuBHQ, a synergistic increase on NO synthesis was shown only in the case of LPS. 
      When phorbol 12-myristate 13-acetate (PMA), a protein kinase C (PKC) activator, 
      was added to the cells 6 hr after the treatment with TG, there was a marked 
      co-operative induction of NO synthesis, even though PMA alone has no effect. 
      Based on the results obtained in this study, we suggest that cytosolic Ca2+ might 
      be enough for the expression of iNOS gene as a priming signal and PKC might be 
      involved in the induction of NO synthesis as a triggering signal by 
      post-transcriptional modification of iNOS mRNA or iNOS itself in the activated 
      murine peritoneal macrophages.
FAU - Park, Y C
AU  - Park YC
AD  - Department of Molecular Biology, Medical Resources Research Centre of Wonkwang 
      University, Iksan, Chonbuk, Korea.
FAU - Jun, C D
AU  - Jun CD
FAU - Kang, H S
AU  - Kang HS
FAU - Kim, H D
AU  - Kim HD
FAU - Kim, H M
AU  - Kim HM
FAU - Chung, H T
AU  - Chung HT
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Immunology
JT  - Immunology
JID - 0374672
RN  - 0 (Hydroquinones)
RN  - 0 (Terpenes)
RN  - 139890-68-9 (1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid 
      acetoxymethyl ester)
RN  - 26XK13B61B (2,5-di-tert-butylhydroquinone)
RN  - 31C4KY9ESH (Nitric Oxide)
RN  - 526U7A2651 (Egtazic Acid)
RN  - 67526-95-8 (Thapsigargin)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Animals
MH  - Blotting, Northern
MH  - Calcium/*physiology
MH  - Cell Culture Techniques
MH  - Egtazic Acid/analogs & derivatives/pharmacology
MH  - Female
MH  - Hydroquinones/pharmacology
MH  - Leukemia, Experimental/immunology
MH  - Macrophage Activation/drug effects/*physiology
MH  - Macrophages, Peritoneal/drug effects/*metabolism
MH  - Mice
MH  - Mice, Inbred C57BL
MH  - Nitric Oxide/*biosynthesis
MH  - Terpenes/pharmacology
MH  - Thapsigargin
PMC - PMC1384288
EDAT- 1996/02/01 00:00
MHDA- 1996/02/01 00:01
PMCR- 1997/02/01
CRDT- 1996/02/01 00:00
PHST- 1996/02/01 00:00 [pubmed]
PHST- 1996/02/01 00:01 [medline]
PHST- 1996/02/01 00:00 [entrez]
PHST- 1997/02/01 00:00 [pmc-release]
AID - 10.1046/j.1365-2567.1996.456544.x [doi]
PST - ppublish
SO  - Immunology. 1996 Feb;87(2):296-302. doi: 10.1046/j.1365-2567.1996.456544.x.