Developmental changes of parathyroid hormone/parathyroid hormone-related peptide and calcitonin receptor binding properties in the chicken calvaria and kidney

Presence of calcitonin receptors in shell gland of the guineafowl and changes in binding property during an oviposition cycle

Radioligand binding assays of membrane fraction of the shell gland endometrium of guineafowl revealed the presence of receptor for calcitonin. The equilibrium dissociation constant (Kd) obtained by Scatchard analyses was 0.50 to 1.25 nM in laying birds and 1.12 to 1.19 nM in nonlaying birds. The maximum binding capacity (Bmax) per milligram of protein was 33.1 to 107.5 femtomoles in laying birds and 101.4 to 114.9 femtomoles in nonlaying birds. Both Kd and Bmax values changed during eggshell formation in laying birds. The results suggest that calcitonin receptor binding may be related to eggshell formation in guineafowl.

Fibrous dysplasia in the maxilla: possible mechanism of bone remodeling by calcitonin treatment

The long-term follow-up case of monostotic fibrous dysplasia of the maxilla in a 10-year-old girl is described with her endocrinologic data and therapeutic consequence of calcitonin administration in association with surgical interventions. The fibrous dysplasia tends to become more quiescent or static after skeletal growth ceases, but the causative has been still unknown to date. In this case reported changes of calciotropic hormones in the serum were well corresponding to the ceasing of the tumor growth at the puberty and reflected to the calcitonin administration. Although calcitonin has been applied to the fibrous dysplasia associated with McCune Albright syndrome, no histologic changes have been described after the calcitonin treatment. This report might be the first description of bone remodeling after the calcitonin treatment for the fibrous dysplasia of the maxilla in immature people. Data of this case may provide a clue to the pathogenesis of fibrous dysplasia. Surgical intervention can be performed after the local bone calcification by a calcitonin treatment, because of alleviation of vigorous hemorrhage by the bone remodeling.