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D Köster

Publications and source records attributed to D Köster.

At least 37 records · Page 2Linked to original sources
PubMed1987

[Craniofacial growth under the influence of blood supply. 5. Brain weight after unilateral interruption of the common carotid artery].

After unilateral ligature of the common carotid artery in rats aged 42 d, the fresh weight of the brain does not deviate from that associated with normal growth in the course of subsequent postnatal development. This is believed to be due to the age at which the ligature was applied and to arterial compensatory mechanisms. The sensitive phases of cerebral development have already come to an end 42 d post partum. Ligature of the right common carotid artery can be fully compensated by circulus arteriosus (Willis), which provides hemodynamic pressure compensation.

Aging↗
PubMed1987

[Craniofacial growth modified by the blood supply. 7. Dry weight of the skull and growth of the mandible].

The dry weight of the skull and jaw bone increases faster in operated rats than in the controls during the fourth and 12 months, but their rates of growth do not differ in the 8th month. The distances measured on the mandible reveal definite sexual dimorphism in the development of the different lengths and heights, these distance being greater in the male rats. Growth in the length of the processes predominated over the growth of the body of the mandible. Local changes in the bone were observed at the points of origin and attachment of muscles.

Animals↗
PubMed1987

[Craniofacial growth under the influence of the blood supply. 6. Metric studies of the skull].

Cephalometric data show that the distances spanning several skull bones also have the highest growth rates. No sexual dimorphism can be observed in the skulls of animals that are six weeks old; such differences do not appear until after the fourth month of life. Allometric studies reveal a relative narrowing of the neurocranium and a relative broadening of the rostrum and zygomatic arch. The broadening of the zygomatic arch complex is related to the postnatal development of the masseter muscle. Vector analysis is used to demonstrate the growth activities of the different parts of the skull. Local changes in the bone during growth was observed in the regions of muscle origin and attachment.

Animals↗
PubMed1987

[Craniofacial growth modified by blood supply. 8. Discussion of normal cranial growth of the rat].

The dimensions of the skull and the dry weight of the skull bones show definite sexual dimorphism. The dynamics of the growth in the skull dimensions and their vectorial presentation show that skull growth in Rattus norvegicus BERKENHOUT is most rapid between the 42nd d and the 4th month of life. This phase is followed by a phase of localized bone growth, which persists up to an age of 300 d. The faster growth of the viscerocranium leads to changes in the proportions of the skull. The relative positions of viscerocranium and mandible and the higher relative position of the dentures are similar to principle to those seen in man. Finally, the morphogenetic effect of the temporalis muscle together with that of the brain in the shaping of the skull are discussed.

Animals↗
PubMed1986

[Craniofacial growth influenced by blood supply. 1. Collaterals and anastomoses following unilateral ligation of the common carotid artery].

The influence of the blood supply on craniofacial growth was investigated in 396 albino rats (Rattus norvegicus Berkenhout). This was done by blocking the right common carotid artery of animals aged 42 d. The rats were slaughtered at previously specified intervals after the operation. The ligature led to dilation of the other major arteries of the neck. Numerous collaterals and anastomoses were also formed. These occurred on the ligature side in the flow region between the proximal and distal stumps of the right common carotid artery, between the flow regions of the right external carotid artery and the right vertebral artery and between the flow regions of the right subclavian artery and the right external carotid artery. Further anastomoses arose between the arteries of the other side, i.e. the rostral thyroid artery, lingual artery, submental artery and labial mandibular artery.

Animals↗
PubMed1986

[Craniofacial growth modified by blood supply. 2. Changes in arterial cross sections and arterial blood supply].

The cross sectional areas of arteries were calculated from their measured thicknesses. The monthly increase in size of the cross sectional area of the aorta is higher in both the controls and the operated animals between the 6th week and 4th month of life than during the subsequent period. The rate at which the cross sectional area of the aorta increased in operated animals was about twice that observed in the controls. The left common carotid artery increased its cross section in the operated animals most rapidly up to the fourth month. The cross sectional areas of all anastomoses increased five-fold by the 12th month of life. The quantities of blood flowing correlated closely with the angiometric values.

Age Factors↗
PubMed1984

[Mechanisms of adaptation and compensation in the rat head after alteration of the arterial system].

The craniofacial growth of the Wistar rat was examined after ligature of the arteria carotis communis dextra. The adaption and compensation processes on the vascular system, skull, brain, masticatory muscle and temporomandibular joint were studied with morphological and functional investigations. The stability regions on the systems of the head were described on growth conditions.

Adaptation, Physiological↗
PubMed1983

[Morphometric and histochemical studies of the masticatory muscles in growing white rats following ligation of the right common carotid artery].

White Wistar rats served for examinations to the masticatory muscles after ligature of the a. carotis communis dextra on the 42nd d after birth. Gravimetric determinations of the dry substance of the muscles were performed in a total of 229 animals. In 65 animals casts of the vessels in synthetic resin (Kallocryl M) were made and the inside diameters of the blood vessels of the corresponding vascular regions measured. Histological, histochemical and muscle-fibre-morphometric observations of the masticatory muscles were made in 10 animals. Due to processes of adaption the a. carotis communis sinistra with an enlarged cross-section supplied the head with an increased blood volume. However, the anatomical and physiologic conditions of the collateral blood vessels conveying blood to the right side of the head prevented the entry of same share of blood into that side. Obviously there is a causal connection between this circumstance and the reduction in the dry substance of the right-side masticatory muscles. Histologic investigations revealed an increase in the capillaries by 10 percent in the animals operated on. The reduction in the diameters of the muscle fibres on the right side of the head was accompanied by a change in the normal combination of fibre types. 2 out of 5 animals which had been operated on showed a fairly homogeneous distribution of the fibre types in the masticatory muscles. Fibres of type 2 tended to be more vulnerable than fibres of type 1. Pathogenetically, the reduction in the dry substance of muscles and the reduction in the diameters of the muscle fibres are caused by nutritive disturbances in connection with restricted circulation. The neuronal-trophic sphere and the mechanism which is responsible for the differentiation of the muscle-fibre types seem to be affected as well. The myokinetic synapses are not affected.

Aging↗