Mice Lacking Platelet-Derived Growth Factor D Display a Mild Vascular Phenotype

Area of Science:

• Vascular Biology
• Developmental Biology
• Genetics

Background:

• Platelet-derived growth factor D (PDGF-D) is the newest member of the PDGF family, with largely unknown biological functions.
• Unlike other PDGFs, PDGF-D has not been studied using gene inactivation in mice.

Purpose of the Study:

• To characterize the biological role of PDGF-D by creating and analyzing a constitutive Pdgfd knockout mouse model.
• To investigate the expression pattern and function of PDGF-D in vivo.

Main Methods:

• Generation of a constitutive Pdgfd knockout mouse model (Pdgfd-/-) with a LacZ reporter.
• Phenotypic analysis of Pdgfd-/- mice, including viability, fertility, and health assessment.
• Localization of Pdgfd promoter activity using the LacZ reporter in various tissues.
• Assessment of vascular structure, specifically NG2-expressing pericytes, and blood pressure measurements.

Main Results:

• Pdgfd knockout mice exhibited a mild phenotype, with viable and fertile offspring.
• Pdgfd expression was primarily observed in vascular structures, particularly in arteries and bifurcations, with endothelial cells as the main source.
• Disorganization of NG2-expressing pericytes in cardiac vasculature and a slight elevation in blood pressure were noted in Pdgfd-/- mice.

Conclusions:

• PDGF-D plays a role in regulating systemic arterial blood pressure.
• The findings suggest PDGF-D is involved in maintaining vascular homeostasis, particularly in arterial structures and associated mural cells.