Extracellular Nucleotides Induce Transient Elevation of Cytosolic Calcium in Articular Chondrocytes

Mechanical stimulation provokes release of nucleotides that can regulate cell behavior by binding to P2Y receptors. Our objective was to test the effect of nucleotides on P2Y receptor activity in live articular chondrocytes by monitoring changes in the concentration of cytosolic free calcium. ATP and UTP induced large transient elevations of calcium in the majority of cells tested (71 of 83 cells and 82 of 147 cells, respectively). In contrast, UDP produced a modest increase of calcium in 21 of 92 cells. ATP, UTP and UDP demonstrated homologous desensitization. There was a significant reduction in response to UTP following pretreatment with ATP and vice versa. However, UDP pretreatment had little effect on the UTP response. In conclusion, at least two subtypes of functional P2Y receptors are present on articular chondrocytes. These P2Y receptors may contribute to the response of cartilage to mechanical stimuli, including those induced by functional orthopedic appliances.

Name thesis:degree_name

M Cl D

Discipline thesis:degree_discipline

Orthodontics

Year dc:date.issued

2007

Author dc:creator

• Tesseyman, Mark A.

Advisors dc:contributor.advisor

• Dixon, S. Jeffrey
• Bernier, Suzanne M.

• ADP
• ATP
• calcium
• cartilage
• chondrocytes
• desensitization
• G protein- coupled receptor
• mechanotransduction
• nucleotide
• P2Y receptor
• signaling
• UDP
• UTP

Handle dc:identifier.uri

https://hdl.handle.net/20.500.14721/20444

OAI identifier oai:identifier

oai:uwo.scholaris.ca:20.500.14721/20444