Reduced cerebral blood flow but elevated cerebral glucose metabolic rate in erythropoietin overexpressing transgenic mice with excessive erythrocytosis

• Verfasst von: Frietsch, Thomas [VerfasserIn]
• Verfasst von: Maurer, Martin H. [VerfasserIn]
• Verfasst von: Vogel, Johannes [VerfasserIn]
• Verfasst von: Gassmann, Max [VerfasserIn]
• Verfasst von: Kuschinsky, Wolfgang [VerfasserIn]
• Verfasst von: Waschke, Klaus F. [VerfasserIn]
• Titel: Reduced cerebral blood flow but elevated cerebral glucose metabolic rate in erythropoietin overexpressing transgenic mice with excessive erythrocytosis
• Verf.angabe: Thomas Frietsch, Martin H Maurer, Johannes Vogel, Max Gassmann, Wolfgang Kuschinsky and Klaus F Waschke
• E-Jahr: 2007
• Jahr: [2007]
• Umfang: 8 S.
• Illustrationen: Diagramme
• Fussnoten: Gesehen am 30.04.2021
• Titel Quelle: Enthalten in: Journal of cerebral blood flow & metabolism
• Ort Quelle: Thousands Oaks, Calif. : Sage, 1981
• Jahr Quelle: 2007
• Band/Heft Quelle: 27(2007), 3, Seite 469-476
• ISSN Quelle: 1559-7016
• DOI: doi:10.1038/sj.jcbfm.9600360
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: autoradiography
• Sach-SW: blood viscosity
• Sach-SW: cerebral metabolism
• Sach-SW: hemodilution
• Sach-SW: oxygen delivery
• K10plus-PPN: 1756678774

Abstract

To examine the impact of excessive erythrocytosis on local cerebral blood flow (CBF) and cerebral glucose metabolic rate (CMRglc), we made use of our constitutively erythropoietin (Epo)-overexpressing transgenic mouse line (tg-6) that reach a mean hematocrit of 0.87. Compared with wild-type (wt) control siblings, CBF decreased by 44% in tg-6 mice, while upon hemodilution (tg-6-HD) to a physiologic hematocrit (e.g., 0.44) tg-6-HD mice returned the CBF to wt levels. Cerebral blood flow was determined in another transgenic mouse line that overexpresses human Epo in the brain only (tg-21): CBF increased by 17% compared with wt controls. However, oxygen delivery was similar in all four mouse groups tested (wt, tg-6, tg-6-HD and tg-21). Mean CMRglc was higher in tg-6 (+72%), tg-6-HD mice (+43%) and tg-21 (+22%) than in wt mice. Local CMRglc was higher in all 40 brain regions in tg-6 but only in 15 and 8 regions in tg-6-HD and tg-21 mice. These results show that prolonged increases in hematocrit did not alter cerebral oxygen delivery at a decreased CBF and increased CMRglc. Hemodilution suggests that high blood viscosity is a cause of the decrease in CBF and partly of the increase in CMRglc. Cerebral glucose metabolic rate may also be increased by a direct effect of Epo in the brain (tg-21 mice).