Development of renin expression in the mouse kidney

Area of Science:

• Nephrology
• Developmental Biology
• Vascular Biology

Background:

• Renin is crucial for blood pressure regulation.
• Its expression pattern in the developing kidney is not fully understood.

Purpose of the Study:

• To elucidate the spatiotemporal development of renin expression in the mouse kidney during fetal and postnatal life.
• To map the three-dimensional development of renin-expressing cells within the intrarenal arterial tree.

Main Methods:

• Immunohistochemistry for renin and alpha-smooth muscle actin (alphaSMA).
• Three-dimensional imaging of mouse kidneys at various developmental stages (fetal and postnatal).

Main Results:

• Renin expression initiated in arcuate arteries by day 14 of development.
• Expression shifted progressively from proximal to distal arterial segments as the vascular tree elaborated.
• Renin expression was observed in established vessel walls, not during active growth, and became restricted to juxtaglomerular afferent arterioles in adulthood.
• Heterogeneity in renin expression was noted across comparable vessel segments at all developmental stages.

Conclusions:

• Renin expression in the developing kidney is a dynamic process, sequentially established in the arterial tree.
• The final adult pattern of renin expression in juxtaglomerular afferent arterioles is achieved through a distal migration and stabilization of expression.
• Understanding this developmental trajectory is key to comprehending renal vascular homeostasis and renin-angiotensin system development.