Quantitative study of the osteoblasts and osteoclasts in the bones of rats during the simulation of weightlessness

Tibia and vertebrae of rats exposed to hypokinesia or head-down suspension were investigated by quantitative histomorphometry. It was found that 35- and 60-day hypokinesia as well as 35-day suspension caused osteoporosis in the tibial and vertebral spongiosa. The development of osteoporosis was accompanied by a significant reduction in the number of osteoblasts in the primary spongiosa of tibia and vertebrae whereas no noticeable changes in osteoclasts were observed either in hypokinetic or suspended rats. The only exception was lumbar vertebrae in which the amount of osteoclasts decreased as a result of 60-day hypokinesia. It is assumed that the reduction in the number and activity of osteoblasts plays the major part in the development of osteoporosis during hypokinesia and suspension.     

Dynamics of the structural recovery of the rat's tibia from suspension-produced osteopenia]

The qualitative histomorphometric techniques were used to study the dynamics of tibia structural recovery from osteopenia in 30 female rats previously suspended by tail for 30 days. The suspension was found to have caused osteopenia in the tibial proximal metaphysis that was fully gone only after 60 day; in other words, readaptation took twice as much time as the osteopenia development. This fact should be taken into consideration by designers of rehabilitative methods.     

Comparative Spectroscopic and HPLC Analyses of Phenolic Compounds in Extracts of Anthocyanin Maize Purple Saratov Variety Grown Under Various Wetting Conditions

Pharmaceutical Chemistry Journal - The quercetin content in aqueous EtOH extracts of covering leaves of anthocyanin Purple Saratov diploid variety of Zea mays L. grown under dry conditions reached...     

Effect of diphosphonates on the development of osteoporosis in the hypokinetic rat

Using histomorphometric methods, the effect of diphosphonates (hydroxydimethylaminopropylene diphosphonic acid and hydroxyethylene diphosphonic acid) on the development of osteoporosis in spongy matter of tibia and vertebrae of the rats exposed to hypokinesia for 60 days was investigated. It was found that aminopropylene diphosphonic acid in the dose 6 mg phosphorus/kg/day prevented osteoporosis and caused an increase in the volume density and abnormal (cartilage rich and poorly ossified) spongy bone. By contrast, ethylene diphosphonic acid in the dose 9 mg phosphorus/kg/day did not prevent osteoporosis but reduced its severity.     

Histomorphometric analysis of the bones of rats exposed to "Cosmos-1887" space flight

Tibia and lumbar vertebrae of rats sacrificed 2 days after their 13-day space flight on Cosmos-1887 were examined histomorphometrically. It was found that the exposure led to osteoporosis of the primary and secondary spongiosa of tibia proximal metaphyses and early signs of bone reduction in the lumbar vertebrae spongiosa. The major cause of osteoporosis was inhibition of bone neoformation which was indicated by a lower number and activity of osteoblasts. A certain contribution was also made by enhanced bone resorption which was proven by a greater number of osteoclasts per bone volume and area unit in the tibia primary spongiosa. The fact that the rats were exposed to 1 G for 48 hours after landing resulted in readaptation developments, which were pointed to by a decrease of acid phosphatase in osteoclasts.