Hydroxyapatite formed on/in agarose gel induces activation of blood coagulation and platelets aggregation.
We reported earlier that hydroxyapatite (HA) formed on/in agarose gels (HA/agarose) produced by alternate soaking process is a bone-filling material possessing osteoconductive and hemostatic effects. This process could allow us to make bone-like apatite that was formed on/in organic polymer hydrogel matrices. Here, we investigated the mechanism of hemostasis induced by HA/agarose and found that HA/agarose, but not agarose or HA powder, significantly shortened activated partial thromboplastin time (APTT). While HA/agarose did not show significant platelet aggregation, it markedly enhanced adenosine diphosphate (ADP)-induced platelet aggregation. Moreover, Western blot analysis revealed selective adsorption of vitronectin onto HA/agarose. We also observed marked differences between HA powder and HA/agarose in their XRD patterns. The crystallinity of HA powder was much higher compared to that of HA/agarose. Furthermore, 50-100 nm of tube-form aggregations was observed in HA powder on the other hand 100-200 nm of particles was observed in HA/agarose by SEM observation. Thus 100-200 nm of low crystallized particles on the surface structure of HA/agarose may play an important role in hemostasis. Our results demonstrated a crucial role of HA/agarose in the mechanism of hemostasis and suggested a potential role for HA/agarose as a bone-grafting material.
Arimura
Shin-ichiro
S
Developmental Therapeutics Course, Oral and Maxillofacial Rehabilitation, Department of Maxillofacial Diagnostic and Surgical Science, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
Kawahara
Ko-ichi
K
Biswas
Kamal Krishna
KK
Abeyama
Kazuhiro
K
Tabata
Masashi
M
Shimoda
Toru
T
Ogomi
Daisuke
D
Matsusaki
Michiya
M
Kato
Shinya
S
Ito
Takashi
T
Sugihara
Kazumasa
K
Akashi
Mitsuru
M
Hashiguchi
Teruto
T
Maruyama
Ikuro
I
D000244:Adenosine Diphosphate / Q000494:pharmacology; D000327:Adsorption; D001777:Blood Coagulation / Q000187:drug effects*; D018786:Bone Substitutes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D017886:Durapatite / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D005782:Gels; D006487:Hemostasis / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010314:Partial Thromboplastin Time; D010974:Platelet Aggregation / Q000187:drug effects*; D011208:Powders; D011517:Prothrombin Time; D012685:Sepharose; D013499:Surface Properties; D019096:Vitronectin / Q000493:pharmacokinetics; D014961:X-Ray Diffraction
D018786:Bone Substitutes; D005782:Gels; D011208:Powders; D019096:Vitronectin; D000244:Adenosine Diphosphate; D012685:Sepharose; D017886:Durapatite