| Abstract: | Abstract The hemocytes of the pericardial body of Ciona intestinalis were studied by electron microscopy. Our findings showed that stem cells, clear vesicular granulocytes, microgranulocytes, unilocular granulocytes and globular granulocytes are present at the periphery of the smaller-sized pericardial bodies. The stem cells are small round cells with a large nucleus, with or without nucleolus, and homogeneous cytoplasm containing numerous ribosomes. The clear vesicular granulocytes are characterized by an ameboid shape and cytoplasm containing several large electron-lucent vacuoles and small electron-dense granules. The microgranulocytes are variable in shape and contain numerous large electron-dense granules. The unilocular granulocytes show a single large vacuole with an electron-dense or electron-lucent content and a thin layer of peripheral cytoplasm that contains the flattened nucleus. The globular granulocytes are characterized by the presence of large vacuoles containing either fibrogranular material or electron-dense aggregates. |
