Histological study of the circulatory system of Sulawesi Medaka fish (Oryzias celebensis) for animal model research

Abstract

Sulawesi medaka fish (Oryzias celebensis) is one part of medaka fish that are endemic in the region of South Sulawesi, Indonesia. This study aims to observe histological structure of the circulatory system of Sulawesi medaka fish. Morphological study showed that the heart is located in the anterior region of the Sulawesi medaka fish body. Histological study of the circulatory of Sulawesi medaka fish showed that the atrium has thin walls whereas the ventricles have thick walls. The contractions of the ventricle have high pressure and then the blood will be pumped through a bulbus arteriosus that is shaped like an onion. Bulbus arteriosus consists of fibroelastic tissue and some smooth muscles. Bulbus arteriosus, is a unique structure and is to dampen the pressure pulse that generated by the ventricle. According to the circulatory system of zebrafish showed that there were similarity between Sulawesi medaka fish and Zebrafish. In general the structure of the circulatory system specially heart and bulbus anteriosus in Sulawesi medaka fish has similarity with Zebrafish as well as other Teleostei fish. This results suggested that Sulawesi medaka fish can be used as model animals especially in the use of fish as animal models in research of cardiovascular disease.