Brain tissue haemoglobin expression in saline-perfused vs non-perfused rodents

Marion Walser; Lars Karlsson; Reza Motalleb; Jörgen Isgaard; H Georg Kuhn; N David Åberg

doi:10.1016/j.heliyon.2023.e23343

Brain tissue haemoglobin expression in saline-perfused vs non-perfused rodents

Heliyon. 2023 Dec 7;10(1):e23343. doi: 10.1016/j.heliyon.2023.e23343. eCollection 2024 Jan 15.

Authors

Marion Walser^{1

2}, Lars Karlsson^{3

4}, Reza Motalleb³, Jörgen Isgaard^{1

5

6}, H Georg Kuhn^{3

7}, N David Åberg^{1

8}

Affiliations

¹ Department of Internal Medicine, Institute of Medicine, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
² Department of Clinical Chemistry, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg, Sweden.
³ Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Sweden.
⁴ The Queen Silvia Children's Hospital, Sahlgrenska University Hospital, Gothenburg, Sweden.
⁵ Department of Specialist Medicine, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg, Sweden.
⁶ Hunter Medical Research Institute, University of Newcastle, Newcastle, NSW, Australia.
⁷ Institute for Public Health, Charité - Universitätsmedizin Berlin, Germany.
⁸ Department of Acute Medicine and Geriatrics, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg, Sweden.

Abstract

Haemoglobin beta (Hbb) and delta-aminolevulinate synthase 2 (Alas2) messenger RNA (mRNA) is mainly found in immature red blood cells, reticulocytes, and not in mature erythrocytes. However, these are also expressed in other tissues such as brain cells, mostly neurons. Therefore, exact quantification of neural tissue homogenates may be confounded by remaining blood in the brain vasculature that may give falsely high values of Hbb/Alas2 expression. To investigate and compare the contribution of local Hbb/Alas2 expression, we investigated mRNA expression locally in the hippocampus and prefrontal cortex, in post-sacrifice saline-perfused and non-perfused mice and rats. Although there was a higher level of Hbb/Alas2 transcripts in the non-perfused animals, there was a significant mRNA expression in perfused brains that could at most partially be explained by remaining blood. Finally, we suggest that saline-perfusion should be recommended for quantification of brain Hbb/Alas2 transcripts in homogenates.

Keywords: 5′-aminolevulinate synthase 2; Brain; Haemoglobin beta; Non-perfused; Rodent; Saline-perfused.