Zur Fr�hentwicklung der herzeigenen Strombahn. Elektronemikroskopische Untersuchung an der Ratte

Henningsen, B.; Schiebler, Theodor Heinrich

doi:10.1007/bf00519962

Cited by 19 publications

(4 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar junctional characteristics also have been described in the capillaries of adult rat myocardium by Bruns and Palade (1968). No open junctions such as those described by Manasek (1971) or by Henningsen and Schiebler (1970) were seen between myocardial capillary endothelial cells at any age studied. We cannot account for the open spaces between endothelial cells as described by other investigators.…”

Section: Discussionsupporting

confidence: 62%

“…Most studies of the developing heart have consisted of light and electron microscopic descriptions of events of cellular organization which occur during cardiac morphogenesis (Dbaly et al, 1968;Henningsen and Schiebler, 1970;Manasek, 1971;Ostadal et al, 1975). From these studies it is possible to deduce the sequence of the formation of functional, histologically recognizable, myocardial microvasculature.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Maturation of myocardial capillaries in the fetal and neonatal rat: An ultrastructural study with a morphometric analysis of the vesicle populations

Porter

Bankston

1987

Am. J. Anat.

View full text Add to dashboard Cite

The ultrastructural morphology of the cellular and extracellular components of the developing myocardial capillary wall--from the 16-day-gestation fetus of the rat to the 21-day neonate--was examined. A morphometric analysis of plasmalemmal vesicles and of coated vesicles and pits of capillary endothelial cells was performed during the same developmental period. As the lateral extensions of the capillary endothelial cells change from irregular to regular in their thickness during development, there is an increase in the number of plasmalemmal vesicles and a progression from clusters of plasmalemmal vesicles to a uniform distribution in the endothelial cell. The ratio of vesicles which are open to the luminal front, which are "free" in the cytoplasm, or which are open to the abluminal front of the endothelial cell was consistent throughout development. The numerical density of plasmalemmal vesicles demonstrates a gradual and significant increase. In contrast, the numbers of coated vesicles and pits are variable within a very narrow range, and no pattern of increase or decrease is discernible during development. Similarly, there is no change in interendothelial cell junctions, which consist of occluding and primitive adhesive junctional types, during development. The lamina densa of the basal lamina gradually develops from discontinuous, patchy densities along the abluminal surface of the endothelial cells to a continuous and distinct layer by 21 days gestation. The presence of the proteoglycan species in the developing basal lamina was assessed with the cationic dye ruthenium red (RR), and the appearance of RR-marked proteoglycans was found to parallel the appearance of lamina densa material. found to parallel the appearance of lamina densa material. The RR sites appear discontinuously in patches; and later, the RR sites appear in a continuous and regular planar lattice in the lamina rara interna and externa at 21 days gestation. A complete array of RR-stainable anionic sites outside a continuous lamina densa near birth indicates that the basal laminae of developing capillaries in the heart are morphologically, and in part biochemically, mature by the end of the first neonatal week. Our results show that the endothelial cells and the subtending basal lamina of myocardial capillaries gradually mature morphologically during the final days of gestation and the first neonatal week.(ABSTRACT TRUNCATED AT 400 WORDS)

show abstract

Section: Discussionsupporting

confidence: 62%

Section: Introductionmentioning

confidence: 99%

Maturation of myocardial capillaries in the fetal and neonatal rat: An ultrastructural study with a morphometric analysis of the vesicle populations

Porter

Bankston

1987

Am. J. Anat.

View full text Add to dashboard Cite

show abstract

“…It is likely that the absence of capillaries between the epicardium and the myocyte layers in embryos of stage 0, could be confirmed by transmission electron microscopy, it is noteworthy that we never found erythrocytes either in the subepicardial space or between the myocytes. We were unable to demonstrate the presence of intramyocardial clefts like those observed in chicken (Tokuyasu, 1985) and rat (Henningsen and Schiebler, 1970) embryos. Therefore, the primary physiological function of the diverticulum from the sinus venosus as well as that of the AV and CV venous rings remains unclear, since no blood circulation seems to occur from the intertrabecular sinusoids to these developing coronary venous vessels.…”

Section: Resultscontrasting

confidence: 62%

Development of the coronary arteries and cardiac veins in the dogfish (Scyliorhinus canicula)

1993

View full text Add to dashboard Cite

The development of the coronary system in the Dogfish was studied using light microscopy. The sample examined consisted of 44 embryos and four newborns. The chronology of events occurring during the process was referred to the total length (TL) of the specimens. The nourishment of the developing myocardium first takes place by means of intertrabecular sinusoids. This system is later switched to a circulation through coronary vessels. The cardiac veins develop earlier than the coronary arteries. The earliest evidence of development of heart vessels in the present sample was the appearance of a diverticulum from the sinus venosus in three embryos of 31 mm TL. This diverticulum outlined the future coronary sinus. Both the atrioventricular and conoventricular venous rings were completely developed in an embryo of 36 mm TL. Coronary artery vessels appeared for the first time in embryos of 40 mm TL. In these specimens, two arteries arose from the midventral hypobranchial artery and divide to give rise to the four coronary artery conal trunks. In a 51-mm TL embryo it was already possible to follow the course of the coronary arteries, from the hypobranchial artery to the conoventricular groove. All main coronary vessels were fully developed in embryos of more than 58 mm TL. However, the arteries supplying the atrium were firstly recorded in a newborn of 77 mm TL. Birth usually occurs when the shark reaches about 72-76 mm TL.

show abstract

“…Since previous reports have described open junctions in developing myocardial capillaries (Henningsen and Schiebler, 1970;Manasek, 19711, carbon was used in these studies to assess the integrity of the interendothelial cell junctions in the developing capillaries. Our previous morphological study of developing myocardial capillaries has demonstrated structurally tight junctions with the characteristic pentalaminar appearance (Porter and Bankston, 1987a); and in the current study, these intercellular junctions were functionally impermeable not only to carbon but also to probes at least as small as myoglobin (3.3 nm), even at the youngest developmental age studied.…”

Section: Discussionmentioning

confidence: 99%

Functional maturation of the capillary wall in the fetal and neonatal rat heart: Permeability characteristics of developing myocardial capillaries

Porter

Bankston

1987

Am. J. Anat.

View full text Add to dashboard Cite

The development of the functional components of the myocardial capillary wall was characterized by time-course studies of transendothelial transport of intravascularly injected probes of graded size from 16 days of gestation in the fetal rat to seven days postpartum. Despite the morphological changes occurring in the developing endothelial cells, the interaction of the probes was similar throughout the developmental period studied. The carbon particles were retained within the capillary lumina without any association with interendothelial junctions or with plasmalemmal vesicles. Carbon also was associated with coated vesicles. In contrast to carbon, ferritin was localized sequentially, over 60 sec of circulation, in plasmalemmal vesicles on the lumenal surface, in the cytoplasm, and on the ablumenal surface of the endothelial cells as well as in the interstitial space. Ferritin was located also in coated pits and vesicles and, after 90 sec of circulation, in multivesicular bodies. Within 30 sec of circulation, reaction product of myoglobin was located in plasmalemmal vesicles, coated vesicles, and transendothelial cell channels. Also within 30 sec, myoglobin partially filled the interendothelial space from the capillary lumina to the level of the tight junction. At all developmental ages studied, the interendothelial cell junctions appeared structurally tight and were impermeable to all of the probes. Once ferritin or myoglobin had reached the ablumenal space, the basal lamina did not appear to restrain the passage of the probes. Plasmalemmal vesicles are the capillary structures which transendothelially transport ferritin and myoglobin in developing myocardial capillaries.

show abstract

Zur Fr�hentwicklung der herzeigenen Strombahn. Elektronemikroskopische Untersuchung an der Ratte

Cited by 19 publications

References 36 publications

Maturation of myocardial capillaries in the fetal and neonatal rat: An ultrastructural study with a morphometric analysis of the vesicle populations

Maturation of myocardial capillaries in the fetal and neonatal rat: An ultrastructural study with a morphometric analysis of the vesicle populations

Development of the coronary arteries and cardiac veins in the dogfish (Scyliorhinus canicula)

Functional maturation of the capillary wall in the fetal and neonatal rat heart: Permeability characteristics of developing myocardial capillaries

Contact Info

Product

Resources

About