title: Propranolol elicits cutaneous analgesia against skin nociceptive stimuli in rats.
abstract: The purpose of this study was to investigate the cutaneous analgesic effect of propranolol and compare with a local anesthetic lidocaine. The potencies and equipotent doses were determined for infiltrative cutaneous analgesia on the rat back by determination of dose-response curves for propranolol and lidocaine. Propranolol as well as lidocaine elicited dose-dependent cutaneous analgesia. On a 50% effective dose (ED(50)) basis, the relative potency was propranolol (10.3 [8.9-11.9]μmolkg(-1))>lidocaine (25.8 [24.3-27.8]μmolkg(-1)) (P<0.01). On equianalgesic doses (ED(25), ED(50), ED(75)), propranolol produced longer action of infiltrative cutaneous analgesia than lidocaine (P<0.01). Coadministration of lidocaine (25.8μmolkg(-1)) and propranolol (1.7μmolkg(-1)) exhibited greater blockade and duration than lidocaine (25.8μmolkg(-1)) or propranolol (1.7μmolkg(-1)) alone. Propranolol displayed more potent and longer duration of action than lidocaine at producing cutaneous analgesia. Furthermore, propranolol may prove useful as an adjuvant for lidocaine in producing cutaneous analgesia.
authors: Department of Physical Therapy, China Medical University, Taichung, Taiwan; Department of Medical Research, Chi-Mei Medical Center, Tainan, Taiwan.
authors: Yu-Wen
authors: YW
authors: Chen
authors: Chin-Chen
authors: CC
authors: Chu
authors: Yu-Chung
authors: YC
authors: Chen
authors: Ching-Hsia
authors: CH
authors: Hung
authors: Jhi-Joung
authors: JJ
authors: Wang
mesh_terms: D000700:Analgesics / Q000494:pharmacology* / Q000627:therapeutic use; D000779:Anesthetics, Local / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D007279:Injections, Subcutaneous; D008012:Lidocaine / Q000494:pharmacology / Q000627:therapeutic use; D008297:Male; D059226:Nociceptive Pain / Q000188:drug therapy / Q000503:physiopathology*; D010147:Pain Measurement; D011433:Propranolol / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000187:drug effects* / Q000503:physiopathology
chemical_list: D000700:Analgesics; D000779:Anesthetics, Local; D008012:Lidocaine; D011433:Propranolol