Hypertension II: Hypertension and Vascular Control

Jeff C. Falcone
jcfalc01@gwise.louisville.edu

Dear Colleague:  We utilize a small glass pipette which is slightly smaller than the diameter of the arteriole.  The pipette is neither heat polished nor siliconized thereby maintaining a somewhat slight abrasiveness.  We then under a dissecting microscope, placed the arteriole under a slight negative pressure (-5 cmH2O).  Then very carefully we advanced the denuding pipette towards the other pipette while holding the edge of the untied vessel with microfine forceps.  The pipette was advanced 3 to 5 times and then reattached to the pipette.  The pipettes must obviously be in the same plane and alignment to avoid damaging the vessel.  We have confirmed this technique by inspecting TEM longitudinal sections - especially taken from the mid point of the vessel where we make our measurements.  The endothelial layer is gone but the basement membrane remains intact.  Pharmacological endothelium independent agents have not significantly different effects before or after the procedure.  Ach dilatory responses are lost after the denudation technique.  The technique is not simple and takes great steadiness in the actual application.  There are some days when even I puncture or slit the vessel while attempting the denudation - obviously those vessels are discarded from our experimental sample.