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
Procedure:
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.
References:
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.