title: IV and IP administration of rhodamine in visualization of WBC-BBB interactions in cerebral vessels.
abstract: Epi-illuminescence intravital fluorescence microscopy has been employed to study leukocyte-endothelial interactions in a number of brain pathologies. Historically, dyes such as Rhodamine 6G have been injected intravenously. However, intravenous injections can predispose experimental animals to a multitude of complications and requires a high degree of technical skill. Here, we study the efficacy of injecting Rhodamine 6G into the peritoneum (IP) for the purpose of analyzing leukocyte-endothelial interactions through a cranial window during real time intravital microscopy. After examining the number of rolling and adherent leukocytes through a cranial window, we found no advantage to the intravenous injection (IV). Additionally, we tested blood from both routes of injection by flow cytometry to gain a very precise picture of the two methods. The two routes of administration failed to show any difference in the ability to detect cells. The study supports the notion that IP Rhodamine 6G works as efficaciously as IV and should be considered a viable alternative in experimental design for investigations employing intravital microscopy. Facilitated intravital studies will allow for more exploration into cerebral pathologies and allow for more rapid translation from the laboratory to the patient with less chance of experimental error from failed IV access.
authors.affiliation: Temple University School of Medicine, Center for Sustance Abuse Research, Philadelphia, Pennsylvania, 19140.|Department of Cellular and Molecular Physiology, Temple University School of Medicine, Philadelphia, Pennsylvania, 19140.
authors.forename: Zachary Wilmer
authors.initials: ZW
authors.lastname: Reichenbach
authors.affiliation: Temple University School of Medicine, Center for Sustance Abuse Research, Philadelphia, Pennsylvania, 19140.|Department of Cellular and Molecular Physiology, Temple University School of Medicine, Philadelphia, Pennsylvania, 19140.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Li
authors.affiliation: Temple University School of Medicine, Biostatistics Consulting Center, Philadelphia, Pennsylvania, 19140.
authors.forename: John P
authors.initials: JP
authors.lastname: Gaughan
authors.affiliation: Department Neurosurgery, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, 19107.
authors.forename: Melanie
authors.initials: M
authors.lastname: Elliott
authors.affiliation: Temple University School of Medicine, Center for Sustance Abuse Research, Philadelphia, Pennsylvania, 19140.|Department of Cellular and Molecular Physiology, Temple University School of Medicine, Philadelphia, Pennsylvania, 19140.
authors.forename: Ronald
authors.initials: R
authors.lastname: Tuma
mesh_terms: D061605:Administration, Intravenous; D000818:Animals; D001808:Blood Vessels / Q000473:pathology*; D001921:Brain / Q000473:pathology*; D042783:Endothelial Cells / Q000166:cytology* / Q000502:physiology; D007274:Injections, Intraperitoneal; D007962:Leukocytes / Q000166:cytology* / Q000502:physiology; D008810:Mice, Inbred C57BL; D008853:Microscopy / Q000379:methods*; D061848:Optical Imaging / Q000379:methods; D012235:Rhodamines / Q000008:administration & dosage*; D013194:Staining and Labeling / Q000379:methods*
chemical_list: D012235:Rhodamines
keywords: cranial window; epi-illuminescence intravital fluorescence microscopy; intraperitoneal injection; leukocyte adhesion; leukocyte rolling; rhodamine 6G