Effect of iontophoretical application of NK1 receptor antagonists on pulpal blood flow in cats.
The influence of NK1 receptor antagonists applied iontophoretically on pulpal blood flow (PBF) was investigated. Along with substance P (SP, 0.8 approximately 20.0 ng/kg) administration to the canine pulp through the catheterized lingual artery, two NK1 receptor antagonists, [D-Pro2,D-Trp7,9]-SP and [D-Pro2,D-Phe7,D-Trp9]-SP (0.2 approximately 3.4 mM) were applied iontophoretically (cathodal current, 0.02 approximately 0.1 mA, 1 min) to the prepared class V dentinal cavity of ipsilateral teeth in 11 generally anesthetized cats. A paired t-test showed that SP administration caused significant increases of PBF (p < 0.05) without changing systemic blood pressure, and that SP and SP antagonist administration caused significantly less increase of PBF than in control of SP and 0.9% saline administration (p < 0.05). These data provide evidence that the iontophoretic application of NK1 receptor antagonists effectively attenuates SP-induced vasodilatation and show the possibility of their use in the control of neurogenic inflammation in the dental pulp.
Kim
Young-Kyung
YK
Department of Conservative Dentistry, School of Dentistry, Kyungpook National University, Daegu, Republic of Korea.
Chu
Wan-sik
WS
Lee
Ho-Jeong
HJ
Ahn
Dong-Kuk
DK
Kim
Sung Kyo
SK
D000818:Animals; D002415:Cats; D003782:Dental Pulp / Q000098:blood supply*; D007478:Iontophoresis; D064729:Neurokinin-1 Receptor Antagonists; D012039:Regional Blood Flow / Q000187:drug effects; D013373:Substance P / Q000008:administration & dosage* / Q000037:antagonists & inhibitors; D014662:Vasoconstrictor Agents / Q000008:administration & dosage*; D014664:Vasodilation / Q000187:drug effects*
D064729:Neurokinin-1 Receptor Antagonists; D014662:Vasoconstrictor Agents; D013373:Substance P