Preclinical model and histopathology translational medicine and renal denervation

The prevalence of resistant hypertension, which is defined as failure to achieve control of blood pressure (BP) (<140/90) despite treatment with optimal doses of three or more antihypertensive medications (including diuretics), is as high as 12-15 % of all hypertensive patients. Renal sympathetic denervation is a new treatment option for resistant hypertension. Catheter-radiofrequency renal denervation has demonstrated its efficacy and safety in the SYMPLICITY I, SYMPLICITY II and EnligHTN trials. However, there are still many unanswered questions in this field, and preclinical studies using animal models may help researchers and clinicians to find answers to those questions. Generally, larger animals such as pig, dog, or sheep are needed for the preclinical study. The swine model is frequently used for the preclinical study, since the anatomy of renovascular system is similar to that of humans. A semi-quantitative ordinal grading system is useful, when the changes of nerves, renal artery, and peri-arterial soft tissue induced by renal denervation are evaluated.