[Further evidence of the role of prostaglandin on the effects of hormones on blood circulation in bones].
In a short communication we demonstrated the inhibitory affect of acetylosalicylic acid (ASA) on the increased bone blood flow and 45Ca and 3H-proline incorporation in oophorectomized (OOX) female rats. This finding suggested probable participation of prostaglandin. The aim of the present work was to confirm and extend the initial observation and to find out, whether the administration of ASA did not affect also the decrease in the bone blood flow after the administration of estradiol benzoate (EB). Local blood flow was determined by means of the uptake of 85Sr-microspheres. In experiment A (females) the local circulatory values were increased after OOX significantly in tibia and distal femur, insignificantly in diaphysis of the femur and calvaria; this increase after OOX was suppressed by simultaneous administration of ASA completely in tibia, partially (and statistically insignificantly) in distal femur and diaphysis of the femur; no effect of ASA could be demonstrated in the calvaria. The blood flow through the kidneys of OOX female rats was decreased after ASA, while no change occurred in muscle and skin. The bone mineral content was significantly lower in both groups of OOX females. In experiment B (males), we observed an increase in local circulatory values after ORX in tibia, distal femur and diaphysis of the femur and suppression of this increase by the administration of ASA. These changes were not demonstrable in the calvaria and soft tissues studied. In experiment C (females), we found that significant decrease in the local circulatory values in the tibia after 4 weeks of administration of EB was not altered by simultaneous administration of ASA. Experiment D (females) proved again that 24 hour incorporation of 45Ca and 3H-proline was markedly suppressed by the administration of ASA not only in OOX females but also in sham operated control rats. Thus, the present results confirm the inhibitory effect of ASA on the increase in bone blood flow after castration, indicating with high probability participation of prostaglandin (PGE2?) (while no effect of ASA could be demonstrated on the decrease in bone blood flow after EB). The described blood flow changes are induced by local vascular reactions and occur in the bones of both female and male rats. Marked suppression by ASA of 45Ca and 3H-proline incorporation supports the circulatory results and indicates an important interconnection between metabolic processes and local circulation in the bone. We conclude that prostaglandin may be one of the factors regulating bone blood flow.
Kapitola
J
J
Laborator pro endokrinologii a metabolismus, 1. lékarská fakulta Univerzity Karlovy, Praha, Czech Republic.
Andrle
J
J
Haas
T
T
Kubícková
J
J
D000818:Animals; D001241:Aspirin / Q000494:pharmacology; D001783:Blood Flow Velocity / Q000187:drug effects; D001842:Bone and Bones / Q000098:blood supply* / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D008297:Male; D010052:Ovariectomy; D011392:Proline / Q000378:metabolism; D011453:Prostaglandins / Q000494:pharmacology*; D051381:Rats; D012039:Regional Blood Flow / Q000187:drug effects
D011453:Prostaglandins; D004958:Estradiol; D011392:Proline; D001241:Aspirin; D002118:Calcium
Dalsí doklady o zprostredkování hormonálních úcinku na kostní krevní obĕh prostaglandinem.