Adrenomedullin is increased by pulsatile shear stress on the vascular endothelium via periodic acceleration (pGz).
Periodic acceleration (pGz) is produced by a platform which moves the supine body repetitively in a headward to footward direction. The imparted motion produces pulsatile shear stress on the vascular endothelium. Pulsatile shear stress on the vascular endothelium has been shown to elicit production of a host of cardioprotective, cytoprotective mediators. The purpose of this study was to ascertain if pGz also enhances production of adrenomedullin (AM) in normal healthy swine. Twelve pigs (weight range 20-30 kg) were anesthetized, intubated and placed on conventional mechanical ventilation. All animals were secured to the motion platform. In one group (pGz) (n=7) was activated for 1h, and monitored for an additional 3h. A control group (CONT) (n=5) served as time control. Arterial blood gases, hemodynamic measurements, and serum for AM, interleukin 4, 6 and thromboxane B(2) (TBXB2) were measured at baseline, immediately after pGz, and 3h after pGz had been discontinued. There was no significant change from baseline value in IL-4, IL-6 or TBXB2. Mean arterial blood pressure decreased in pGz-treated animals from 115+/-10 at baseline to 90+/-8 after 60 min of pGz (p<0.01). AM levels increase from 776+/-176 pg/ml baseline to 1160+/-68 pg/ml immediately after pGz, and remained elevated to 1584+/-160 pg/ml, 3h after pGz (p<0.01 vs. BL). This is the first report of AM-enhanced production using a non-invasive method of increasing pulsatile shear stress on the vascular endothelium. pGz increases production of AM in normal healthy swine. These changes are independent of IL-4, IL-6 or TBXB2 production.
Department of Cellular, Molecular, and Developmental Neurobiology, Instituto Cajal, CSIC, Madrid, Spain.
Alfredo
A
Martínez
Jaqueline
J
Arias
Jorge A
JA
Bassuk
Heng
H
Wu
Paul
P
Kurlansky
Jose A
JA
Adams
D000054:Acceleration; D000136:Acid-Base Equilibrium; D053607:Adrenomedullin / Q000097:blood*; D000818:Animals; D001158:Arteries / Q000502:physiology; D001784:Blood Gas Analysis / Q000379:methods; D004730:Endothelium, Vascular / Q000502:physiology*; D011673:Pulsatile Flow / Q000502:physiology*; D033081:Shear Strength; D013552:Swine
D053607:Adrenomedullin