Changes in bone cellularity elicited by PTHrP in wild type and <i>Igf1</i>-null mice

<p>. Osteoblasts (A) and osteoclasts (B) lining trabecular surface were counted in the tibial metaphysis of mice of both genotypes, treated or untreated with each PTHrP tested, and their number were represented <i>per</i> bone tissue area (T.Ar), as described in the text. Values are expressed as mean ± SEM corresponding to 2 males and 2 females for each genotype and treatment. (C) BMSCs from two (1 male and 1 female) wild type (WT) or five (2 males and 3 females) <i>Igf1</i>-null mice were cultured for 16 days, with PTHrP (1–36) (Nt) or osteostatin (Ost) (each at 100 nM), or saline vehicle. Matrix mineralization was determined by alizarin staining by measuring absorbance at 620 nm. Values are mean ± SEM (corresponding to 7 culture wells <i>per</i> experimental condition). Statistical differences were assessed by ANOVA followed by post-host Bonferroni test. *p<0.05; **p<0.01 <i>vs</i> vehicle-treated WT.