{"id":{"repo_id":"uwo","oai_identifier":"oai:uwo.scholaris.ca:20.500.14721/20444"},"canonical_url":"https://search.dev.ndltd.org/etd/uwo/oai:uwo.scholaris.ca:20.500.14721/20444","repository":{"repo_id":"uwo","name":"Western University","base_url":"https://uwo.scholaris.ca/server/oai/request"},"display":{"title":"Extracellular Nucleotides Induce Transient Elevation of Cytosolic Calcium in Articular Chondrocytes","abstract":"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.","abstract_html":"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.","abstract_has_math":false,"creators":["Tesseyman, Mark A."],"institution":null,"degree_name":"M Cl D","degree_level":null,"degree_discipline":"Orthodontics","degree_department":null,"school":null,"contributors":[],"advisors":["Dixon, S. Jeffrey","Bernier, Suzanne M."],"committee_chairs":[],"committee_members":[],"year":2007,"date_issued":"2007-01-01","date_published":"2007-01-01","updated_at":"2026-07-27T21:55:59Z","subjects":["ADP","ATP","calcium","cartilage","chondrocytes","desensitization","G protein- coupled receptor","mechanotransduction","nucleotide","P2Y receptor","signaling","UDP","UTP"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/20.500.14721/20444","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Dixon, S. 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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."]},{"key":"dc:title","label":"Title","values":["Extracellular Nucleotides Induce Transient Elevation of Cytosolic Calcium in Articular Chondrocytes"]}]}],"canonical_facts":{"dc:contributor.advisor":["Dixon, S. Jeffrey","Bernier, Suzanne M."],"dc:creator":["Tesseyman, Mark A."],"dc:date.accessioned":["2025-06-25T19:24:06Z"],"dc:date.available":["2025-06-25T19:24:06Z"],"dc:date.issued":["2007-01-01"],"dc:description.abstract":["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."],"dc:identifier.uri":["https://hdl.handle.net/20.500.14721/20444"],"dc:subject":["ADP","ATP","calcium","cartilage","chondrocytes","desensitization","G protein- coupled receptor","mechanotransduction","nucleotide","P2Y receptor","signaling","UDP","UTP"],"dc:title":["Extracellular Nucleotides Induce Transient Elevation of Cytosolic Calcium in Articular Chondrocytes"],"dc:type":["thesis"],"thesis:degree_discipline":["Orthodontics"],"thesis:degree_name":["M Cl D"]},"updated_at":"2026-07-27T21:55:59Z"}