Abstract P387: Depletion of Perivascular Macrophages in the Brain Delays Blood Pressure Elevation in Angiotensin II-salt Hypertensive Rats

Objectives: Perivascular macrophages in the cerebrospinal fluid (CSF) are immune surveillance cells in the brain. Increase in angiotensin II (Ang II) in the periphery gradually produces neurogenic hypertension which is associated with brain inflammation. However, little is known on the role of perivascular macrophages in the CSF on neurogenic hypertension. We hypothesized that perivascular macrophages in the CSF have an important role in the development of neurogenic hypertension by relaying and amplifying excess peripheral Ang II signals to brain parenchyma. Methods: Sprague-Dawley rats had surgery to instrument radio telemetric pressure transducers to abdominal aorta. Following a one-week recovery period, the rats had surgery to implant either saline or Ang II filled osmotic minipump subcutaneously and received intracerebroventricular (icv) injection of either control liposome or clodronate liposome. The clodronate liposome is a drug that selectively induces apoptosis to macrophages which have liposome ...