Developmental changes of the glycolytic enzymes in the human fetal heart.

The ontogeny of hexokinase, phosphofructokinase, phosphoglucoisornerase, aldolase, pyruvate kinase and lactate dehydrogenase activities which are associated with glycolysis, an important energy yielding process, has been studied in human fetal heart for periods ranging from 13 weeks to above 33 weeks of gestation. Hexokinase, phosphoglucoisomerase and pyruvate kinase activities show similar developmental profiles exhibiting maximum activity at 25-28 weeks ofgestation. Phosphofructokinase activity, on the other hand, shows a minimum at this period and exhibits a peak value at early stages (13-16 weeks of gestation). Though considerable activity for aldolase is observed at an early period, it declines thereafter, but again increases in the later period. The probable role and correlations of these glycolytic enzymes with energy demand and general functional development in human fetal heart in ontogeny are evaluated.

THE PRIMARY MYOCARDIAL TISSUE CULTURE OF HUMAN FETUS: SCANNING ELECTRON MICROSCOPIC OBSERVATIONS ON DEVELOPMENT AND FORMATION OF INTERCALATED DISC IN CARDIAC MUSCLE CELLS / 解剖学报

Morphological features of the developing human fetal cardiac muscle cells in culture was observed with scanning electron microscope. Myocardial tissue masses were isolated from three human fetus of 10, 13 and 16 week's gestation. They were cultured in vitro. New cardiac muscle cells grew and detached from the tissue masses. In the early stage (about one week) the cardiac muscle cells which detached from the tissue masses and grew on the glass slide were spherical or short spindle in shape. There were various processes on the surface of the cells. In the middle stage (about two to four weeks) the cells became irregular in shape. The processes extended from the surface of the cells and formed the intercellular connection. In the later stage (more than one month) part of the cells in culture developed and appeared rod shape. The intercellular connection was composed of the intercalated disc-like structure, the rod-shaped cells joined together and formed branched structures. In the development of human fetus in culture a continuous process of the formation of the intercalated disc-like structure was observed. It was found that the developed cells were gradually arranged in bundles running parallel to their long axis. This kind of structure looked like normal mature morphological feature of cardiac muscle cells. It is therefore considered that the cardiac muscle cells in culture may have possibility to differentiate into mature cardiac muscle.