title: Alterations of voltage-dependent K(+) channels in the mesenteric artery during the early and chronic phases of diabetes.
abstract: This study investigated the alteration of voltage-dependent K(+) (Kv) channels in mesenteric arterial smooth muscle cells from control (Long-Evans Tokushima Otsuka [LETO]) and diabetic (Otsuka Long-Evans Tokushima Fatty [OLETF]) rats during the early and chronic phases of diabetes. We demonstrated alterations in the mesenteric Kv channels during the early and chronic phase of diabetes using the patch-clamp technique, the arterial tone measurement system, and RT-PCR in Long-Evans Tokushima (LETO; for control) and Otsuka Long-Evans Tokushima Fatty (OLETF; for diabetes) type 2 diabetic model rats. In the early phase of diabetes, the amplitude of mesenteric Kv currents induced by depolarizing pulses was greater in OLETF rats than in LETO rats. The contractile response of the mesenteric artery induced by the Kv inhibitor, 4-aminopyridine (4-AP), was also greater in OLETF rats. The expression of most Kv subtypes- including Kv1.1, Kv1.2, Kv1.4, Kv1.5, Kv1.6, Kv2.1, Kv3.2, Kv4.1, Kv4.3, Kv5.1, Kv6.2, Kv8.1, Kv9.3, and Kv10.1-were increased in mesenteric arterial smooth muscle from OLETF rats compared with LETO rats. However, in the chronic phase of diabetes, the Kv current amplitude did not differ between LETO and OLETF rats. In addition, the 4-AP-induced contractile response of the mesenteric artery and the expression of Kv subtypes did not differ between the two groups. The increased Kv current amplitude and Kv channel-related contractile response were attributable to the increase in Kv channel expression during the early phase of diabetes. The increased Kv current amplitude and Kv channel-related contractile response were reversed during the chronic phase of diabetes.
authors.affiliation: Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Da Hye
authors.initials: da H
authors.lastname: Hong
authors.affiliation: Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Hongliang
authors.initials: H
authors.lastname: Li
authors.affiliation: Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Hye Won
authors.initials: HW
authors.lastname: Kim
authors.affiliation: Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Han Sol
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Youn Kyoung
authors.initials: YK
authors.lastname: Son
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Se-Ran
authors.initials: SR
authors.lastname: Yang
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Kangwon National University School of Medicine, Chuncheon, South Korea.|Institute of Medical Sciences, Kangwon National University, Chuncheon, South Korea.
authors.forename: Jeong-Ran
authors.initials: JR
authors.lastname: Park
authors.affiliation: Department of Molecular and Cellular Biochemistry, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Kwon-Soo
authors.initials: KS
authors.lastname: Ha
authors.affiliation: Department of Medical Environmental Biology and Tropical Medicine, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Eun-Taek
authors.initials: ET
authors.lastname: Han
authors.affiliation: Department of Internal Medicine, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Seok-Ho
authors.initials: SH
authors.lastname: Hong
authors.affiliation: Department of Pulmonary, Critical Care and Sleep Medicine, University of Southern California, Keck School of Medicine, Los Angeles, CA, USA.
authors.forename: Amy L
authors.initials: AL
authors.lastname: Firth
authors.affiliation: Institute of Medical Sciences, Department of Obstetrics and Gynecology, Kangwon National University Hospital, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Sung Hun
authors.initials: SH
authors.lastname: Na
authors.affiliation: Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea.
authors.forename: Won Sun
authors.initials: WS
authors.lastname: Park
mesh_terms: D000208:Acute Disease; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002908:Chronic Disease; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000378:metabolism* / Q000503:physiopathology; D005786:Gene Expression Regulation / Q000187:drug effects; D008638:Mesenteric Arteries / Q000187:drug effects / Q000378:metabolism* / Q000503:physiopathology; D026902:Potassium Channel Blockers / Q000494:pharmacology; D024642:Potassium Channels, Voltage-Gated / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051381:Rats; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D001786:Blood Glucose; D026902:Potassium Channel Blockers; D024642:Potassium Channels, Voltage-Gated
keywords: LETO; OLETF; mesenteric artery; type 2 diabetes; voltage-dependent K+ channel