Increased nervous system-specific enolases in rat plasma and cerebrospinal fluid in bilirubin encephalopathy detected by an enzyme immunoassay.

Three forms of enolase isozymes (alpha alpha, alpha gamma, gamma gamma), including nervous system-specific forms, were measured in the cerebrospinal fluid and the blood plasma of jaundiced or nonjaundiced infant rats by means of enzyme immunoassay systems capable of detecting each form of enolase at the 1 amol (10(-18) mol) level. Average enolase levels in cerebrospinal fluid in normal rat were 2.0, 0.2 and 0.1 pmol/ml for alpha alpha, alpha gamma, gamma gamma forms, respectively. Levels of alpha gamma and gamma gamma forms (nervous system-specific enolases; NSE) in jaundiced rats, which suffer Purkinje cell degeneration due to the inborn hyperbilirubinemia, were three to four times as high as the normal values. When kernicterus was induced in jaundiced rats by an injection of bucolome, the NSE level in cerebrospinal fluid was elevated up to more than 30-fold the control, together with a significantly higher level of alpha gamma form in blood plasma are helpful in detecting neuronal damage in the central nervous system.