| Project/Area Number |
11671440
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Orthopaedic surgery
|
|---|
| Research Institution | Ehime University |
|---|
Principal Investigator |
KAWATANI Yoshiyuki (2000) Ehime University School od Medicine Assistant Professor, 医学部, 講師 (60274320)
奥村 秀雄 (1999) 愛媛大学, 医学部, 助教授 (60115813)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OGATA Tadanori Ehime University School od Medicine Instructor, 医学部, 助手 (30291503)
|
|---|
| Project Period (FY) |
1999 – 2000
|
| Project Status |
Completed (Fiscal Year 2000)
|
| Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 2000: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 1999: ¥900,000 (Direct Cost: ¥900,000)
|
|---|
| Keywords | joint cartilage / adenosine / apoptosis / cell death |
|---|
| Research Abstract |
Adenosine receptor agonists were tested for cell proliferation and cell viability in cultivated chondrocytes from rabbit joint cartilage. The addition of Cl-adenosine, an unselective adenosine receptor agonist, remarkably inhibited chondrocyte proliferation detected by [3H]-thymidine uptake test. The IC50 value of Cl-adenosine was about 5 μM.Proliferation of cultured chondrocytes were also inhibited by the addition of adenosine which was further enhanced by the inhibition of adenosine deaminase with EHNA.The exposure to Cl-adenosine induced cell death measured by MTT assay in a dose-dependent manner. The EC50 value of Cl-adenosine was about 30 μM.Exposure to 100 μM Cl-adenosine for 12 hours killed most of the chondrocytes cultured from rabbit joint cartilage. To elucidate which receptor subtype was responsible for both the Cl-adenosine-induced cell death and the inhibition of cell proliferation, we tested several selective adenosine receptor agonists for both MTT assay and [3H]-Thymidine uptake test. The compounds we used were R-PIA (A1 ; 200 nM), CGS-21680 (A2a ; 200 nM), NECA (A2b ; 200 nM), APNEA (A3 ; 200 nM) and CV-1808 (A4 ; 2 μM). All the conventional selective adenosine receptor agonists showed no significant effect on both proliferation and viability in cultured chondrocytes. We also tested the adenosine receptor antagonists such as DPCPX (A1 ; 100 nM), DMPX (A2 ; 10 μM) and sulphophenyl-theophilline (A1/A2 ; 10 μM) on the effect of Cl-adenosine. These antagonists did not show any inhibitory action on the effect of 30 μM Cl-adenosine in both [3H]- Thymidine uptake test and MTT assay. These results suggest that the effect of adenosine on cultured chondrocytes may involve the mediation via atypical adenosine receptor.
|
