title: Cerebral microvascular effects of nimodipine in combination with soman.
abstract: Nimodipine, a calcium antagonist, has been shown to increase the detoxification of soman. In this study the cerebral microcirculatory effects of nimodipine and the acetylcholinesterase inhibitor soman was studied. Anaesthetised rats were administered nimodipine, 10 mg kg(-1) or vehicle intra-peritoneally, and 1h later exposed to 45 μg kg(-1) soman intravenously. The regional blood flows were measured using the microsphere method. Nimodipine and soman markedly increased the cerebral blood flow (CBF) and reduced the vascular resistance. Total CBF increased by 146% after nimodipine and by 105% after soman administration. Combined administration of nimodipine and soman caused additional but not fully additive effects on CBF and vascular resistance, indicating possible different mechanisms of the two agents. A part of the nimodipine induced increased detoxification after AChE-inhibition may be associated with this cerebral vasodilation.
authors.affiliation: Department of Pharmacology and Clinical Neuroscience, Division of Neurosurgery, Umeå University, S-90185 Umeå, Sweden. Lars-Owe.Koskinen@neuro.umu.se
authors.forename: Lars-Owe D
authors.initials: LO
authors.lastname: Koskinen
authors.forename: Magnus
authors.initials: M
authors.lastname: Runnerstam
authors.forename: Mona
authors.initials: M
authors.lastname: Koch
authors.forename: Britt M
authors.initials: BM
authors.lastname: Karlsson
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D002800:Cholinesterase Inhibitors / Q000633:toxicity*; D008297:Male; D008833:Microcirculation / Q000187:drug effects*; D009553:Nimodipine / Q000633:toxicity*; D051381:Rats; D012039:Regional Blood Flow / Q000187:drug effects; D012999:Soman / Q000633:toxicity*; D014655:Vascular Resistance / Q000187:drug effects; D014665:Vasodilator Agents / Q000633:toxicity*
chemical_list: D002800:Cholinesterase Inhibitors; D014665:Vasodilator Agents; D009553:Nimodipine; D012999:Soman; D000110:Acetylcholinesterase