Novel sites of expression of functional angiotensin II receptors in the late gestation fetus   总被引：11，自引：0，他引：11  

M A Millan  P Carvallo  S Izumi  S Zemel  K J Catt  G Aguilera 《Science (New York, N.Y.)》1989,244(4910):1340-1342

In the adult, the peptide hormone angiotensin II (AII) is primarily known as a regulator of circulatory homeostasis, but recent evidence also suggests a role in cell growth. This study of AII in late gestation rat fetuses revealed the unexpected presence of receptors in skeletal muscle and connective tissue, in addition to those in recognized adult target tissues. The AII receptors in this novel location decreased by 80 percent 1 day after birth and were almost undetectable in the adult. Studies in fetal skin fibroblasts showed that the receptors were coupled to phospholipid breakdown, with concomitant increases in inositol phosphate and cytosolic calcium. The abundance, timing of expression, and unique localization of functional AII receptors in the fetus suggest a role for AII in fetal development.  相似文献   

Changes in the morphology and functions of vacuoles during the death of ray parenchyma cells in <Emphasis Type="Italic">Cryptomeria japonica</Emphasis>     

Izumi Arakawa  Ryo Funada  Satoshi Nakaba 《Journal of Wood Science》2018,64(3):177-185

Changes in the morphology and functions of vacuoles provide useful information about the mechanism of cell death. In the present study, we monitored the morphology and contents of vacuoles during the death of ray parenchyma cells in the conifer Cryptomeria japonica. In differentiating xylem, ray parenchyma cells had large central vacuoles. In sapwood, vacuoles in ray parenchyma cells contained proteins, an indication that one of the main functions of these vacuoles might be protein storage. A dramatic decrease in the protein content of some vacuoles was detected in the intermediate wood before the initiation of vacuole rupture. Although vacuole rupture was detected from the intermediate wood to the outermost heartwood, some vacuoles were obviously enlarged in the inner intermediate wood. Condensed nuclei were first observed after the rupture of these large vacuoles in ray parenchyma cells. It seems plausible that the autolysis of the contents of ray parenchyma cells might be caused by the rupture of the enlarged vacuoles in the inner intermediate wood.  相似文献