Spinal subarachnoid perfusion of rhesus monkeys.

A technique of spinal subarachnoid perfusion is descirbed which effectively isolates the spinal cord from the remainder of the central nervous system. A method of obtaining and analyzing spinal cord tissue after subarachnoid perfusion is presented. The spinal subarachnoid space of 12 rhesus monkeys was perfused with [14C]sucrose, [14C]ethylenediaminetetraacetic acid-calcium complex (EDTA), and dextran blue as test substances. The sucrose and EDTA spinal cord distribution spaces are 13.6 +/- 0.9% in white matter and 18.1 +/- 1.4% in gray matter. The diffusion coefficient in tissue of sucrose is 1.7 x 10(-6) cm2/s and of EDTA is 1.55 x 10(-6) cm2/s. The spinal cord tortuosity factor is 2.0-2.1. Six rhesus monkeys were infused intravenously with [3H]sucrose and [14C]EDTA; the spinal capillary exchange half-time from blood to extracellular fluid was greater than 6 h for both sucrose and EDTA.