A novel aortic coarctation model for studying hypertension in the pig.
We have developed a reproducible renovascular model of hypertension via a controllable, suprarenal aortic coarctation in the pig. This model has many potential applications, including investigation of the effects of acute hypertension in the conscious animal; identification of cardiac and vascular adaptations to chronic hypertension and their reversal; determining the effect of pharmacologic agents or other interventions on hypertension; and furthering our understanding of the implications of chronic hypertension on neurologic function. A totally implantable system was devised by attaching a reinforced silicone vascular occluder to a vascular access port. The occluder was placed around the suprarenal aorta proximal to the diaphragm. Ten pigs were made hypertensive by sequentially inflating the occluder. In six pigs, telemetric monitoring of blood pressure was used to determine when the pigs had reached target pressures (mean arterial blood pressure >150 mm Hg). Four pigs did not have telemetry units placed and blood pressure and heart rate were monitored for 4 weeks by periodically restraining the pigs in a sling. Two pigs reversed their occlusion due to presumed technical errors; the remaining pigs were studied for 4 (n = 5) or 8 (n = 3) weeks and then euthanized. Advantages of this model of aortic coarctation are that the occlusions are performed in awake animals and excessive occlusion of the aorta resulting in neurologic dysfunction or other distress to the animal can be easily corrected by simply withdrawing a small amount of the fluid used for inflation of the occluder. Additionally, removal of the constriction does not require a second surgical procedure.
Fossum
Theresa W
TW
Michael E. DeBakey Institute for Comparative Cardiovascular Sciences and Biomedical Devices, College of Veterinary Medicine, Texas A&M University, College Station, Texas 77843-4474, USA. tfossum@cvm.tamu.edu
Baltzer
Wendy I
WI
Miller
Matthew W
MW
Aguirre
Maria
M
Whitlock
Debbi
D
Solter
Phil
P
Makarski
Lori A
LA
McDonald
Michelle M
MM
An
Mi-Young
MY
Humphrey
Jay D
JD
D000450:Aldosterone / Q000097:blood; D000818:Animals; D001017:Aortic Coarctation / Q000503:physiopathology; D001794:Blood Pressure; D004195:Disease Models, Animal; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D012083:Renin / Q000097:blood; D013556:Swine, Miniature; D013686:Telemetry
D000450:Aldosterone; D012083:Renin