A brief description is given of the discovery of PTHrP and the roles of the peptide in mammalian physiology. Next, the occurrence of PTHrP in the earliest vertebrates, sharks, skates and fishes, is reviewed and the calciotropic functions of PTHrP are addressed more specifically in fishes. Parathyroid hormone-related protein (PTHrP) is a hypercalcemic hormone in teleostean fishes, but also has p...

Glomerulonephritis is characterized by the proliferation and apoptosis of mesangial cells (MC). The parathyroid-hormone related protein (PTHrP) is a locally active cytokine that affects these phenomena in many cell types, through either paracrine or intracrine pathways. The aim of this study was to evaluate the effect of both PTHrP pathways on MC proliferation and apoptosis. In vitro studies we...

Parathyroid hormone-related protein (PTHrP) is a regulatory peptide that has been associated with normal fetal growth and differentiation as well as the regulation of fetal calcium. We recently demonstrated the expression of PTHrP in neuroendocrine cells of human prostatic glands. The present study was undertaken to determine if semen contained PTHrP and to determine if there were any differenc...

Epidermal growth factor (EGF) produced rapid and striking effects on parathyroid hormone-related protein (PTHrP) gene expression in the immortalized human keratinocyte cell line, HaCaT. Steady-state levels of PTHrP mRNA and secreted PTHrP were increased 10-fold by maximally effective concentrations of EGF. EGF increased both PTHrP gene transcription and PTHrP mRNA stability. Nuclear run-on assa...

PTHrP is necessary for the formation of the embryonic mammary gland and, in its absence, the embryonic mammary bud fails to form the neonatal duct system. In addition, PTHrP is produced by the breast during lactation and contributes to the regulation of maternal calcium homeostasis during milk production. In this study, we examined the role of PTHrP during post-natal mammary development. Using ...

Parathyroid hormone-related protein (PTHrP) is a growth inhibitor for alveolar type II cells. Type II cell proliferation after lung injury from 85% oxygen is regulated, in part, by a fall in lung PTHrP. In this study, we investigated lung PTHrP after injury induced by >95% oxygen in rats and rabbits. In adult rats, lung PTHrP rose 10-fold over controls to 6,356 +/- 710 pg/ml (mean +/- SE) at 48...

We investigated the mechanisms of parathyroid hormone-related peptide (PTHrP)-mediated effects on osteogenic cells in primary rat bone marrow cell (BMC) cultures. We first demonstrated by reverse transcriptase-polymerase chain reaction and immunocytochemistry that BMCs express the type I parathyroid hormone/PTHrP receptor. Treatment with PTHrP increased osteogenic cell proliferation as determin...

Parathyroid hormone-related protein (PTHrP) is a protein member of the parathyroid hormone family that regulates the dynamic balance between blood and bone calcium during lactation. However, the mechanism of its regulation is not very clear. In order to establish a framework for further functional studies of the PTHrP gene in goat mammary gland epithelial cells during the lactation period, PTHr...

PTH-related protein (PTHrP) is produced in vascular smooth muscle, where it is postulated to exert vasorelaxant properties by activation of the PTH/PTHrP type 1 receptor. As a model for studying the actions of locally produced PTHrP in vascular smooth muscle in vivo, we developed transgenic mice that overexpress the PTH/PTHrP receptor (PTHrP-R) in smooth muscle. Oocyte injection with a SMP8-PTH...

Parathyroid hormone-related protein (PTHrP), a paraneoplastic protein expressed by two-thirds of human non-small cell lung cancers, has been reported to slow progression of lung carcinomas in mouse models and to lengthen survival of patients with lung cancer. This study investigated the effects of ectopic expression of PTHrP on proliferation and cell cycle progression of two human lung adenocar...