Endothelin I

Clinical Significance:
Endothelin I is a 21 amino acid peptide produced primarily by vascular endothelial cells.  It is also produced by renal mesangial and epithelial cells.  Endothelin I has potent effects on peripheral vascular resistance, renal blood flow and glomerular filtration rate.  Endothelin I appears to be a mediator of hypertension and acute renal failure of hemolytic uremic syndrome.  Levels of Endothelin I are increased in patients with hemolytic uremic syndrome with hypertension anuria and oligonuria.  Endothelin I has potent vasoconstriction properties.  Endothelin I stimulates the oppositive vasodilator called Endothelium Derived Releasing Factor.  Levels are also increased in trauma patients.

Reference Range:
4.0 – 9.0 pg/ml

Endothelin I  is measured by direct radioimmunoassay.

Patient Preparation:
Patient should not be on any ACTH, Corticosteroid or hypertension medications, if possible,  for at least 48 hours prior to collection of specimen.

Specimen Collection:
3 ml serum or EDTA plasma should be collected and separated as soon as possible.  Minimum specimen size is 1 ml.

Special Specimens:
For tumor/tissue and various fluids (i.e. CSF, peritoneal, synovial, etc.), contact the Institute for requirements and special handling.

Shipping Instructions:
Ship specimens frozen in dry ice.

1. RL Siegler, SS Edwin, RD Christofferson, and MD Mitchell.  Endothelin in the Urine of Children with the Hemolytic Uremic Syndrome.  Pediatrics 88: 1063-1066, 1991.

2. WL Miller, MM Redfield and JC Burnett Jr.  Integrated Cardiac, Renal and Endocrine Actions of Endothelin.  Journal of Clinical Investigations 83: 317-320, 1989.