title: Changes in purinergic signalling in developing and ageing rat tail artery: importance for temperature control.
abstract: This study aimed to examine the expression and function of P2 receptors of the rat tail and mesenteric arteries during maturation and ageing (4, 6 and 12 weeks, 8 and 24 months). Functional studies and receptor expression by immunohistochemistry revealed a heterogeneous phenotype of P2 receptor subtypes depending on artery age. The purinergic component of nerve-mediated responses in the tail artery was greater in younger animals; similarly responses to ATP and alpha,beta-meATP and the expression of P2X1 receptors decreased with age. Contractile responses to 2-MeSADP decreased with age, and were absent at 8 and 24 months; P2Y1 receptor expression followed this pattern. UTP-induced contractions and P2Y2 receptor expression also decreased with age. The mesenteric artery contracted to UTP, responses at 4 and 6 weeks were larger than at other ages although P2Y2 receptor expression did not significantly differ with age. 2-MeSADP induced relaxation of the mesenteric artery, responses being greatest at 6 weeks and decreased thereafter, which was mimicked by the P2Y1 receptor immunostaining. We speculate that the dramatic changes in expression of P2 receptors in the rat tail artery, compared to the mesenteric artery, during development and ageing are related to the role of the tail artery in temperature regulation.
authors.affiliation: Autonomic Neuroscience Centre, Royal Free and University College Medical School, Rowland Hill Street, London NW3 2PF, UK.
authors.forename: Anna
authors.initials: A
authors.lastname: Wallace
authors.forename: Gillian E
authors.initials: GE
authors.lastname: Knight
authors.forename: Tim
authors.initials: T
authors.lastname: Cowen
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Burnstock
mesh_terms: D000244:Adenosine Diphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000375:Aging / Q000502:physiology*; D000818:Animals; D001158:Arteries / Q000254:growth & development / Q000294:innervation* / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D007150:Immunohistochemistry; D008297:Male; D008638:Mesenteric Arteries / Q000254:growth & development / Q000502:physiology; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000254:growth & development / Q000502:physiology; D009638:Norepinephrine / Q000494:pharmacology; D011224:Prazosin / Q000494:pharmacology; D058910:Purinergic P2 Receptor Agonists; D058919:Purinergic P2 Receptor Antagonists; D051381:Rats; D017207:Rats, Sprague-Dawley; D018048:Receptors, Purinergic P2 / Q000502:physiology*; D012039:Regional Blood Flow / Q000187:drug effects / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D013498:Suramin / Q000494:pharmacology; D013623:Tail / Q000098:blood supply / Q000294:innervation; D013873:Thionucleotides / Q000494:pharmacology; D014544:Uridine Triphosphate / Q000494:pharmacology
chemical_list: D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D058910:Purinergic P2 Receptor Agonists; D058919:Purinergic P2 Receptor Antagonists; D018048:Receptors, Purinergic P2; D013873:Thionucleotides; C002480:methylthio-ADP; D013498:Suramin; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D014544:Uridine Triphosphate; D009638:Norepinephrine; D011224:Prazosin