title: Monitoring dynamic alterations in calcium homeostasis by T1-mapping manganese-enhanced MRI (MEMRI) in the early stage of small intestinal ischemia-reperfusion injury.
abstract: Manganese-enhanced MRI studies have proven to be useful in monitoring physiological activities associated with calcium ions (Ca(2+)) due to the paramagnetic property of the manganese ion (Mn(2+)), which makes it an excellent probe of Ca(2+) . In this study, we developed a method in which a Mn(2+)-enhanced T1 -map MRI could enable the monitoring of Ca(2+) influx during the early stages of intestinal ischemia-reperfusion (I/R) injury. The Mn(2+) infusion protocol was optimized by obtaining dose-dependent and time-course wash-out curves using a Mn(2+)-enhanced T1-map MRI of rabbit abdomens following an intravenous infusion of 50 mmol/l MnCl2 (5-10 nmol/g body weight (BW)). In the rabbit model of intestinal I/R injury, T1 values were derived from the T1 maps in the intestinal wall region and revealed a relationship between the dose of the infused MnCl2 and the intestinal wall relaxation time. Significant Mn(2+) clearance was also observed over time in control animals after the infusion of Mn(2+) at a dose of 10 nmol/g BW. This technique was also shown to be sensitive enough to monitor variations in calcium ion homeostasis in vivo after small intestinal I/R injury. The T1 values of the intestinal I/R group were significantly lower (P < 0.05) than that of the control group at 5, 10, and 15 min after Mn(2+) infusion. Our data suggest that MnCl2 has the potential to be an MRI contrast agent that can be effectively used to monitor changes in intracellular Ca(2+) homeostasis during the early stages of intestinal I/R injury.
authors.affiliation: Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Da-wei
authors.initials: DW
authors.lastname: Zhao
authors.affiliation: Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Le-tian
authors.initials: LT
authors.lastname: Zhang
authors.affiliation: Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Hai-yun
authors.initials: HY
authors.lastname: Cheng
authors.affiliation: Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Yu-long
authors.initials: YL
authors.lastname: Zhang
authors.affiliation: Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Jia-yan
authors.initials: JY
authors.lastname: Min
authors.affiliation: Department of Pathology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Hua-liang
authors.initials: HL
authors.lastname: Xiao
authors.affiliation: Department of Radiology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D003287:Contrast Media / Q000493:pharmacokinetics; D006706:Homeostasis; D007089:Image Enhancement / Q000379:methods; D007410:Intestinal Diseases / Q000378:metabolism* / Q000473:pathology; D007421:Intestine, Small / Q000378:metabolism* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008345:Manganese / Q000493:pharmacokinetics*; D011817:Rabbits; D015427:Reperfusion Injury / Q000378:metabolism* / Q000473:pathology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014018:Tissue Distribution
chemical_list: D015415:Biomarkers; D003287:Contrast Media; D008345:Manganese; D002118:Calcium
keywords: MRI; T1 mapping; calcium channel; calcium homeostasis; ischemia-reperfusion injury; manganese chloride; manganese-enhanced MRI; small intestine