From the oxygen microprofiles Dr. Lauridsen showed that the pre-retinal (PRV) oxygen level on the inside of the retina in the white-blooded Chaenocephalus aceratus icefish was high with a decreasing oxygen level towards the outer portion of the retina. This oxygen profile was inverted compared to the red-blooded Nototehnia coriiceps that had the highest oxygen content in the choroid rete mirabile (CRM) on the outside of the retina where oxygen is secreted from hemoglobin (Figure 2).
The white-blooded icefish has a high vascularization and increased blood supply on the inside of the retina compared to related red-blooded fish (confirmed with ultrasound). The results indicated that the oxygenation follows the high degree of vascularization in the icefish and that increased blood supply is a way of maintaining the oxygen supply in the retina of the icefish.
The study provides new insights about the vascularization and oxygen supply in the retina of icefish and hopefully these results can contribute to a better understanding of eye diseases like age related macular degeneration and diabetic retinopathy which are both characterized by an increased vascularization in the eye.