An improved method for using cisternal cerebrospinal fluid in conscious rats for application in the measurement of catecholamines.

This paper describes an improved method for the application of cerebrospinal fluid (CSF) in conscious rats. The modified polyethylene catheter was chronically inserted into the cisterna magna through a hole drilled in the skull of an anesthetized rat. Fifty microliters of CSF was taken from the recovered conscious rat for radioenzymatic analysis of catecholamines. The values of noradrenaline were 540 +/- 142 pg/ml (mean +/- S.D., n = 50) in Wistar rats and 494 +/- 175 (42) in spontaneously hypertensive rats. However, values of adrenaline and dopamine were less than the lower limits for detection.