title: Thermal Sensitivity and Dimethyl Sulfoxide (DMSO).
abstract: Dimethyl sulfoxide (DMSO) is commonly used as a solvent for hydrophobic substances, but the compound's innate bioactivity is an area of limited understanding. In this investigation we seek to determine the analgesic potential of DMSO. We addressed the issue by assessing the perception of thermal pain stimulus, using a 55 °C hotplate design, in conscious mice. The latency of withdrawal behaviors over a range of incremental accumulative intraperitoneal DMSO doses (0.5-15.5 g/kg) in the same mouse was taken as a measure of thermal endurance. The findings were that the latency, on average, amounted to 15-30 s and it differed inappreciably between the sequential DMSO conditions. Nor was it different from the pre-DMSO control conditions. Thus, DMSO did not influence the cutaneous thermal pain perception. The findings do not lend support to those literature reports that point to the plausible antinociceptive potential of DMSO as one of a plethora of its innate bioactivities. However, the findings concern the mouse's footpad nociceptors which have specific morphology and stimulus transduction pathways, which cannot exclude DMSO's antinociceptive influence on other types of pain or in other types of skin. Complex and as yet unresolved neural mechanisms of perception of cutaneous noxious heat stimulus should be further explored with alternative experimental designs.
authors.affiliation: Clinical Research Center, National Hospital Organization Murayama Medical Center, 2-37-1 Gakuen, Musashimurayama, 208-0011, Tokyo, Japan.|Fujita Memorial Nanakuri Institute, Fujita Health University, 423 Oodori-cho, Tsu, 514-1296, Mie, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Takeda
authors.affiliation: Clinical Research Center, National Hospital Organization Murayama Medical Center, 2-37-1 Gakuen, Musashimurayama, 208-0011, Tokyo, Japan. m_pokorski@hotmail.com.|Public Higher Medical Professional School in Opole, 68 Katowicka St, 45-060, Opole, Poland. m_pokorski@hotmail.com.
authors.forename: Mieczyslaw
authors.initials: M
authors.lastname: Pokorski
authors.affiliation: Clinical Research Center, National Hospital Organization Murayama Medical Center, 2-37-1 Gakuen, Musashimurayama, 208-0011, Tokyo, Japan.
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Okada
mesh_terms: D000818:Animals; D003451:Cryoprotective Agents / Q000494:pharmacology*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology*; D006358:Hot Temperature / Q000009:adverse effects*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010146:Pain / Q000188:drug therapy* / Q000209:etiology
chemical_list: D003451:Cryoprotective Agents; D004121:Dimethyl Sulfoxide
keywords: Analgesia; Dimethyl sulfoxide; Nociception; Noxious heat; Pain; Perception; Thermal stimulus