Reparative Osteogenesis under Dehydration
O.V. Slisarenko, V.I. Bumeister
Sumy State University, Department of Human Anatomy
Sumy, st. Sanatornaya, 31
E-mail: tatis80@list.ru
The problem of bones regeneration in modern medicine remains topical. The percentage
of posttraumatic complications is quite high since a lot of external factors affect the reparative
osteogenesis. Hence reparative bones regeneration requires deeper research for further solution
of this problem.
Materials and methods. Reparative bones regeneration peculiarities under cellular
dehydration were researched on 72 aged laboratory male rats which were divided into two sets:
control and experimental. The latter set of animals was divided into three groups depending on
the dehydration level: low, medium and high. Cellular dehydration was modeled in the following
way: the rats drank 1.2% sodium chloride hypertonic solution and ate granular formula feed. The
animal’s tibia was fractured on reaching the necessary dehydration level. The rats were derived
from the experiment by decapitation under ether anesthesia in 3, 15 and 24 days after the
fracture. The traumatized shin bones were taken for histological study.
Results and discussion. The defect was completely filled with hematoma in 3 days
after the operation. The newly formed regenerate is characterized by cellular texture
abnormality. Every next dehydration level resulted in decreased number of fibroblasts and
macrophages and increased quantity of lymphocytes, pamaquines and neutrophils in comparison
with the control group of animals.
On the 15th day after the fracture one can observe fibroreticular, lammellarand splenial
tissues in the regenerate, i.e. the typical tissues for this period. Reparative osteogenesis processes
disturbance, especially on medium and high levels, is characterized by remains of granulation
tissue which are not typical for this reparation period and were not observed in the control group.
Every next level results in increased fibroreticular tissue content and decreased area of lamellar
and splenial bone tissues. The lamellar tissue consists of thin trabeculas with a small number of
osteoblasts on their surface. The quantity of osteoblasts and trabeculas thickness decreases with
every next dehydration level. The splenial bone tissue is mainly presented by primary osteons.
On the 24th day after the fracture the callus was formed by lamellar and splenial bone
tissues, but the latter differs from the control in quality and quantity. The splenial bone tissue is
presented by primary osteons with disruptions between bone lamellas and separate resorptive
lacunas. One can observe thin bone beams of lamellar tissue with numerous disruptions, separate
osteoblasts and empty osteocyte lacunas. On medium and high level the space between
trabeculas is filled with the remains of fibroreticular tissue, which was not observed in the
control set of animals. Disruptions between the maternal bone and the defect are also observed.
Conclusion. The dysfunctions of reparative regeneration in aged animals can be observed
on the low level of cellular dehydration. The high level of dehydration results in more dangerous
abnormality. Forming of all tissue structures of the regenerate is inhibited causing general
inhibition of the callus formation.