Morphological Сharacterization of the Spinal Cord Regeneration in Adult Desert Killifish Aphaniops hormuzensis (Aphaniidae)

Morphological characterization of the lumbar spinal cord regeneration process was investigated in killifish A. hormuzensis, by using hematoxylin-eosin staining after spinal cord injury. An spinal cord injury was settled, and the injured tissue was sampled. Immediately after the spinal cord injury, the blood clot formation was detected at the injury epicenter and the ependymal layer, and at six hours post-injury (6 hpi), the inflammation and cavity formation occurred. The neural cell accumulation and beginning signs of the spinal cord regeneration were detected one-day post-injury (1 dpi) close to the ependymal layer and subependymal layer. In two 2 dpi, the tissue repair and regeneration progress were detected. The reformation of the ependymal canal happened at 3 dpi, followed by the completion of spinal cord regeneration at 5 dpi. The spinal cord regeneration potency in A. hormuzensis is relatively higher than in other traditional fish models. Studies on the regeneration of this interesting fish are new, therefore, further investigations are needed to explore additional information about various aspects of tissue regeneration. This study is important because killifishes have a short life span, show high environmental variation tolerance, and are easy to maintain and breed in laboratory conditions.