Pulmonary artery catheterization in the rat. 
A method of pulmonary artery (PA) catheterization in the closed-chest rat is described.  This catheterization is best accomplished with teflon catheters having a "shepherd's crook" tip.  Catheter preparation is detailed.  The functional advantages of such a PA catheter are: 1) the tip can remain free within the right ventricle (RV) without becoming occluded by contact with the ventricular wall, and 2) entry into the PA is simple and reproducible.  Dual catheterization of the RVand PA produced only a small systolic gradient (3 mmHg) across the pulmonic valve.  We concluded that the PA catheter does not unduly obstruct blood flow through this valve.