Autonomy of tendon development in the embryonic chick wing

Development ◽  
1979 ◽  
Vol 49 (1) ◽  
pp. 153-165
Author(s):  
Madeleine Kieny ◽  
Alain Chevallier
Keyword(s):  
Cell Death ◽  
Chick Embryos ◽  
Embryonic Chick ◽  
Muscle Belly ◽  
Tendon Development ◽  
Extensor Muscles ◽  
X Irradiation ◽  
Further Development ◽  
Distal Direction ◽  
Somitic Mesoderm

The aim of this study performed in the embryonic chick wing is to test the ability of the tendons to form and develop in the absence of the muscle bellies. The experiments were performed on 2-day chick embryos by destroying a portion of the somitic mesoderm by local X-irradiation. The irradiated part included the wing somite level 15—20 and extended three somites (or presumptive somites) in front and two to six presumptive somites in the rear of the wing somite level. The wings of the operated side were examined histologically 3—8 days after the X-irradiation. The radio-destruction of the somitic mesoderm totally inhibited or severely impaired the development of the forearm muscles. But, despite the absence of the flexor and extensor muscles the differentiation of the distal manus tendons could be observed. This differentiationoccurred at the same time and in the same position as in controls. However, these tendons were transient structures. They disappeared within three days after their individuation. Two mechanisms that progressed in proximo-distal direction were involved in their resorption: cellular dislocation and cell death. We conclude that tendons start to develop autonomously from the muscle bulks, but for their maintenance and further development they require connexion to a muscle belly.

scholarly journals Limb-somite relationship: effect of removal of somitic mesoderm on the wing musculature

Development ◽  
1978 ◽  
Vol 43 (1) ◽  
pp. 263-278
Author(s):  
Alain Chevallier ◽  
Madeleine Kieny ◽  
Annick Mauger
Keyword(s):  
The Other ◽  
Chick Embryos ◽  
Forearm Muscles ◽  
X Irradiation ◽  
Both Bones ◽  
Somitic Mesoderm

The aim of this study is to test the ability of the intrinsic wing musculature to develop in the absence of somitic mesoderm. The experiments were performed on 2- to 2.5-day chick embryos either by replacing the somitic mesoderm adjacent to the wing field with a piece of 9-day chick embryonic midgut or by destroying, through local X-irradiation, not only the somitic mesoderm of the wing level, but also at least three somites (or presumptive somites) anterior and/or three presumptive somites posterior to the wing level. The replacement of somitic tissue scarcely affected the organogenesis of the forearm musculature, at least when both bones were present. In the other experiments, radio-destruction severely impaired the development of the forearm muscles, which were seldom all present and in most cases were entirely missing. The absence of a given muscle involves the simultaneous absence of the corresponding tendons. The possible origins of the muscles that formed despite the removal of the somitic mesoderm are discussed.

Dexamethasone Effect on Embryonic Chick Respiratory Epithelium

1982 ◽  
Vol 40 ◽  
pp. 248-249
Author(s):  
M.R. Richter ◽  
R.V. Blystone
Keyword(s):  
Lung Development ◽  
Critical Role ◽  
Respiratory Epithelium ◽  
Chick Embryos ◽  
Embryonic Chick ◽  
White Leghorn ◽  
Lung Maturation ◽  
Synthetic Analogs ◽  
Lung Physiology ◽  
Avian Lung

Dexamethasone and other synthetic analogs of corticosteroids have been employed clinically as enhancers of lung development. The mechanism(s) by which this steroid induction of later lung maturation operates is not clear. This study reports the effect on lung epithelia of dexamethasone administered at different intervals during development. White Leghorn chick embryos were used so as to remove possible maternal and placental influences on the exogenously applied steroid. Avian lung architecture does vary from mammals; however, respiratory surfactant produced by the lung epithelia serves an equally critical role in avian lung physiology.

scholarly journals Loss of potassium from embryonic chick hearts in potassium-free media with and without calcium

1938 ◽  
Vol 124 (837) ◽  
pp. 446-450
Keyword(s):  
Phosphate Buffer ◽  
Direct Evidence ◽  
Watch Glass ◽  
Chick Embryos ◽  
Embryonic Chick ◽  
Intercellular Spaces ◽  
Experimental Solution ◽  
Free Media ◽  
And Control ◽  
Day By Day

Experiments already described (Murray 1938) led to the inference that the cells of the chick embryonic heart lose potassium in potassium-free media. The experiments here described provide direct evidence of this. The hearts were dissected out of 2 ½-3 day chick embryos and placed in the solution PC (Table I) until they had started to beat. They were then thoroughly washed, and were allowed to lie for 5 min. (2 min. in Exp. 1) in the last wash. This last wash is called control A. The solutions used for washing were from the same flasks as the experimental solution. After their passage through control A the hearts were transferred to 2 c.c. of the experimental solution in a Jena watch-glass. After various times in this the hearts were discarded and both the experimental solution and control A were collected. If the experiment extended over more than 1 day the experimental solution and control A were used over again day by day until all the hearts in the experiment had passed through them. The use of control A was necessary for two reasons: ( a ) to show that potassium was not still being washed out of the intercellular spaces at the end of washing ( b ) in experiments lasting over several days the washing solution was fresh each day, but the experimental solution was of course not changed. Hence any small amount of potassium being carried over from the last wash would accumulate in the experimental solution because of the daily increment and might seriously affect the result; but by leaving the hearts for several minutes in the last wash (control A) and by not changing it for fresh on successive days, any such increase would be detected in that solution. In addition to control A, a daily sample (control B) was taken from the same flasks as the solutions used for washing. Details of the solutions are given in Table I ; a phosphate buffer was always used.

Motor projection patterns to the hind limb of normal and paralysed chick embryos

Development ◽  
1982 ◽  
Vol 72 (1) ◽  
pp. 269-286
Author(s):  
N. G. Laing
Keyword(s):  
Spinal Cord ◽  
Cell Death ◽  
Hind Limb ◽  
Muscle Volume ◽  
Chick Embryos ◽  
Relative Contribution ◽  
Hind Limbs ◽  
Lateral Motor Column ◽  
Before And After ◽  
Major Period

Counts were made of the number of motoneurons innervating the hind limbs of 10-day normal and paralysed chick embryos whose right hind limb buds had been subjected to varying degrees of amputation prior to innervation. The number of motoneurons on the intact sides of the paralysed embryos was found to be similar to the number present in normal embryos prior to the major period of motoneuron death. Since it has previously been shown that paralysis does not increase the number of motoneurons generated, this means that normal motoneuron death was largely prevented in the paralysed embryos. There were differences in the distributions of motoneurons in the rostrocaudal axis of the spinal cord between normal and paralysed embryos. Therefore, cell death does not eliminate a uniform fraction of motoneurons throughout the rostrocaudal extent of the chick embryo lumbar lateral motor column. It is also argued that there are differences in the relative contribution of the various lumbosacral levels to different parts of the limb, e.g. the shank, before and after the period of cell death. In both normal and paralysed embryos there was a linear relationship between the volume of limb muscle which developed after amputation and the number of motoneurons surviving in the spinal cord. There was no evidence of a ‘compression’ of motoneurons into the remaining muscle either after amputation alone or after amputation combined with paralysis. Motoneurons are therefore rigidly specified for certain parts of the limb. The relationship between motoneuron number and muscle volume on the amputated side differed from that of the intact side. For a similar increase in muscle volume there was a smaller increase in motoneuron number on the intact sides. This suggested a parallel to the paradoxically small increase in motoneuron number that occurs on the addition of a supernumerary limb.

scholarly journals THE CULTIVATION OF TISSUES FOR PROLONGED PERIODS IN SINGLE FLASKS

1936 ◽  
Vol 64 (1) ◽  
pp. 121-130 ◽  
Author(s):  
Raymond C. Parker
Keyword(s):  
Cell Death ◽  
Chick Embryo ◽  
Connective Tissue ◽  
Breast Muscle ◽  
Cell Multiplication ◽  
Tyrode Solution ◽  
Low Level ◽  
Further Development

1. Fragments of breast muscle from a 12 day old chick embryo have been kept alive in single flasks for an entire year without being transferred. The nutrient materials were supplied by frequent applications of adult fowl serum diluted with Tyrode solution. 2. When fragments of fixed tissues are cultivated in serum, cell multiplication and cell death are both reduced to an extremely low level. 3. The presence of a plasma coagulum is not essential to the continued survival and further development of tissues cultivated inserum. 4. The fibrinogen, prothrombin, and fibrin of coagulated plasma are not essential to the development of connective tissue fibers in vitro.

scholarly journals A Study of Late Ventral Body Wall Degeneration in the Embryonic Chick, with Special Reference to the Cell Cycle

2021 ◽  
Author(s):  
◽  
Peter Barwell
Keyword(s):  
Cell Cycle ◽  
Cell Death ◽  
Body Wall ◽  
Morphological Changes ◽  
Cell Loss ◽  
Tissue Growth ◽  
Embryonic Chick ◽  
Cell Death Pathway ◽  
Medial Migration

<p>The cell kinetics and morphological changes during late ventral body wall development of the embryonic chick were studied, particularly midline degeneration and the medial migration of lateral tissues. An histological examination of these events was undertaken, along with autoradiography to determine the duration of the cell cycle, followed by teratological studies involving the prevention of differentiative events in the cell death pathway, using BrDU and Janus B Green as agents. The effects of cell cycle blockade on rates of cell death were also examined, as was the tissues ability to express differentiative features in vitro. Ventral body wall (VBW) cell death was classified as apoptosis, and was involved in two distinct events. Medial migration of lateral tissues began at day 5 of development, with widespread VBW apoptosis being seen by day 6, limited to the original mesoderm of the region. A later precise line of apoptosis (the VBL), involving both ectodermal cells of the midline ectodermal ruffle and the underlying mesodermal cells, was observed at day 7, spreading in a rostral to caudal fashion down the embryo, appearing as the migratory lateral tissues fused in the midline body wall. Increases in the amount of cell death are matched by decreases in the MI, such that at its peak (day 7.5 of development) the cell death rate is sufficiently greater than both the cell proliferation and immigration rates that a state of negative tissue growth ensues. The histological half-life of the apoptotic bodies approximates 3.8 hours. The ability to undergo apoptosis at day 7 is dependent upon a differentiative event around day 4 of incubation, and involves signal mechanisms intrinsic to the VBW tissues. BrDU application was found to inhibit apoptotic differentiation, in contrast to Janus B Green, which had a more generalised teratogenic effect on the region as a whole. Tissue culturing experiments revealed that an ectodermal-mesodermal interaction is important in regulating the extent of mesodermal apoptosis, the ectoderm playing a maintenance role for the mesoderm. Dead cells derive from the cycling cell population, as shown by the occurrence of labelled dead cells after autoradiography, and by the prevention of apoptosis by a cell cycle blockade, and by the production of a semi-synchronised wave of apoptoses after release of this blockade. These cell blockading results further suggest that entry into the apoptotic death program requires cells to be in a particular cell cycle stage, and it seems most likely that the decision to die was made in early G1. Tissue and cell growth rates, cell loss and death rates, cell birth rates and cell immigration rates were all determined for the VBW region throughout the time period studied.</p>

Rôle du mésoderme somitique dans le développement du plumage dorsal chez l'embryon de Poulet

Development ◽  
1972 ◽  
Vol 28 (2) ◽  
pp. 343-366
Author(s):  
Par Annick Mauger
Keyword(s):  
Early Stage ◽  
Cervical Region ◽  
Lumbar Region ◽  
Chick Embryos ◽  
A Chain ◽  
Normal Differentiation ◽  
Time Of Operation ◽  
Somitic Mesoderm ◽  
Axial Organs

The role of somitic mesoderm in the development of dorsal plumage in chick embryos. II. Regionalisation. Transplantation and inversion experiments were performed on the somitic mesoderm of 2- to 2·5-day chick embryos in order to study the role of regional and axial determinations in the development of the dorsal plumage. The transposition of a piece of somitic mesoderm from the posterior cervical region (where the spinal pteryla is narrow) to the thoraco-lumbar region (where it is wide) leads to a local and unilateral narrowing of the spinal pteryla at the operation site. Conversely, the transposition of somitic mesoderm from the thoraco-lumbar region to the posterior cervical region results in a local and unilateral widening of the spinal pteryla. Consequently at the time of operation the segmented or not yet segmented somitic mesoderm is already determined to give rise to a definite transverse level of the spinal pteryla. The inversion of the cephalo-caudal polarity of a piece of somitic mesoderm without the ectodermal covering, or of a portion of the axial organs deprived of the overlying ectoderm has no effect on the orientation of feather filaments and feather rows. In contrast, the inversion of the cephalo-caudal polarity of a portion of the axial organs together with the overlying ectoderm results in the development of feathers growing in a cephalad direction and feather chevrons opening towards the head of the embryo. The inversion of the dorso-ventral polarity of a piece of somitic mesoderm does not prevent the normal differentiation of feathers in the operated region. The inversion of the medio-lateral polarity of a piece of unsegmented somitic mesoderm has little effect on the development of the spinal pteryla. On the contrary, the medio-lateral inversion of a chain of somites precludes the formation of the feathers at the level of operation. The somitic mesoderm, even when segmented, is endowed with extensive regulative capacity of its axes, except for the medio-lateral polarity, which is fixed irreversibly at the time of segmentation. The regional determination of the feather-forming somitic mesoderm is acquired at an early stage, at any rate before segmentation. However, at a given transverse level of the cephalo-caudal axis, the somitic cells remain totipotent as concerns their histo-genetic destiny (dermatome, myotome, or sclerotome) until after the onset of segmentation.

Sign in / Sign up

Export Citation Format

Share Document