A rapid method for isolating rabbit renal microvessels

A technique has been described to isolate rabbit renal preglomerular microvessels using an infusion of a magnetized iron oxide suspension into the renal artery. An initial separation of the vascular tissue was performed with a magnet and a final separation was performed using a nylon sieve allowing nonvascular, tubular, and glomerular contaminants to be filtered free from the microvessels. Light and electron microscopy showed morphology consistent with interlobular arteries and afferent arterioles. The purity of the preparation was greater than 95%. In the absence of exogenous arachidonic acid, the microvessels were able to synthesize prostacyclin (7.5 +/- 1.2 ng.mg protein-1.min-1) in excess of prostaglandin E2 (2.2 +/- 0.7 ng.mg protein-1.min-1). The tissue exhibited a time-dependent increase in prostanoid biosynthesis up to 60 min and responded to stimulators (e.g., melittin and arachidonic acid) and inhibitors (e.g., meclofenamate and indomethacin) of prostanoid biosynthesis. These studies indicate that a high-yielding and versatile preparation of renal preglomerular microvessels can be rapidly obtained. The microvessels are viable and may represent an excellent model for studying a variety of biochemical interactions under in vitro conditions.