The ultrastructure of certain components of the corpora cardiaca in orthopteroid insects

摘要: Corpora cardiaca of freshly molted male Leucophaea maderae and Periplaneta americana, prepared in the standard manner for electron microscopy, are seen to possess numerous membrane-limited “sacs” granules. These “sacs”, reaching 5 μ width, appear be bulbous axon terminals brain neuro-secretory cells or processes intrinsic glandular cells. The often close juxtaposition with corpus cardiacum Closely packed granules within some these structures approach 150 mμ others 300 diameter. frequently have a limiting membrane. Although nuclei cell bodies been rather infrequently, micrographs included reveal that elements rough-surfaced endoplasmic reticulum, mitochondria and, occasionally, large, dense granule. Tissue sometimes separated by unlined, optically empty spaces, tracheoles, extensions connective tissue sheath, which penetrate between considerable depth.