[Anabolic action of teriparatide to osteoporotic patients].

Intermittent administration of human parathyroid hormone (PTH) [1-34], or teriparatide, has been used for osteoporotic treatment, which is available for daily and weekly administration for the osteoporotic patients in Japan, increasing bone mass and reduce bone fracture risk. In general, continuous PTH infusion shows catabolic effects in bone, while the intermittent administration of PTH results in anabolic action in osteoporotic patients. Intermittent PTH administration promotes preosteoblastic proliferation, as well as stimulates osteoblastic bone formation dependent on cell coupling with osteoclasts.

Histological Effects of the Combined Administration of Eldecalcitol and a Parathyroid Hormone in the Metaphyseal Trabeculae of Ovariectomized Rats.

Intermittent administration of human parathyroid hormone (1-34) (hPTH(1-34)) promotes anabolic action in bone by stimulating bone remodeling, while eldecalcitol, an analog of active vitamin D3, suppresses osteoclastic bone resorption, and forms new bone by minimodeling. We have examined the biological effects of combined administration of eldecalcitol and hPTH(1-34) on 9-week-old Wistar rats that underwent an ovariectomy (OVX) or Sham operation. They were divided into a Sham group, OVX with vehicle (OVX group), OVX with 10 µg/kg/day of hPTH(1-34) (PTH group), OVX with 20 ng/kg/day of eldecalcitol (eldecalcitol group) or OVX with 10 μg/kg/day of hPTH(1-34), and 20 ng/kg/day of eldecalcitol (combined group) for 4 or 8 weeks.

Sclerostin is differently immunolocalized in metaphyseal trabecules and cortical bones of mouse tibiae.

Sclerostin, an osteocyte-derived molecule, has been reported to serve as a negative regulator of osteoblastic activity as well as bone remodeling. However, there is no report that verified the regional difference for sclerostin synthesis, and in this study we have investigated immunolocalization of sclerostin by comparing dentin matrix protein (DMP) 1, an osteocyte-derived factor broadly expressed in tibial metaphyses and cortical bone. In metaphyseal primary trabecules, a site of bone modeling, strong DMP1-reactivity was observed in osteocytic lacunar-canalicular system (OLCS), while faint staining for sclerostin was visible only in a few osteocytes.

[Encouragement for developing research mind of dental students].

The School of Dental Medicine in Japan nurtures well-trained professionals who are at the cutting edge of the present knowledge in the fields of Dentistry and Dental Technology. As an important part of its mission, many Schools of Dental Medicine in Japan, including Hokkaido University, also encourages dental students to pursue basic research in the many aspects of Dentistry. It is of importance to cultivate research-minded students in Dental Medicine.