Plasma beta-endorphin during clinical and experimental ischaemic pain

Plasma beta-endorphin during clinical and experimental ischaemic pain

Bach FW; Fahrenkrug J; Jensen K; Dahlstrom G; Ekman R

Scandinavian Journal Of Clinical And Laboratory Investigation

1987

Female; Humans; Male; Adult; Aged; Middle Aged; beta-Endorphin/blood; Biomarkers of Pain; Radioimmunoassay/methods; Angina Pectoris/blood; Blood Specimen Collection; Exertion; Muscles/physiology; Myocardial Infarction/blood; Pain/blood/etiology; Tourniquets

An improved radio-immunoassay using an antiserum directed towards the N-terminal part of the endogenous opioid peptide beta-endorphin 1-31 (beta-EP) was validated and applied to a study of beta-EP in plasma during ischaemic pain. Experimental ischaemic pain induced in seven healthy volunteers by the submaximal effort tourniquet test did not change plasma beta-EP or adrenocorticotrophin. Plasma beta-EP was determined in 21 patients with acute myocardial infarction (AMI) and in seven patients with unstable angina pectoris. Plasma beta-EP was 4.9 fmol/ml with 95% confidence limits, 3.2-7.8 fmol/ml in AMI patients at admittance, and 2.9 (2.0-3.4) fmol/ml one week later in stable and pain-free condition (p less than 0.05). The level in 49 healthy persons was 2.8 (2.4-2.9) fmol/ml. Elevated beta-EP levels were found in five AMI patients with cardiogenic shock and in four AMI patients dying within 24 h after admittance compared to the rest of AMI patients (p less than 0.02). beta-EP was not elevated during unstable angina pectoris, although pain scores were similar to AMI. The AMI group revealed a significant, although weak, positive correlation between plasma beta-EP and pain score (Spearman r = 0.49, p less than 0.05), while there was no correlation during unstable angina pectoris. beta-EP was not correlated to the amount of morphine required within the 48 h after admittance of AMI patients. We conclude that the increase of beta-EP in plasma during AMI may be due to stressful factors other than ischaemic pain and that it is questionable whether beta-EP in plasma is related to antinociception.

1987

Article information provided for research and reference use only. PedPalASCNET does not hold any rights over the resource listed here. All rights are retained by the journal listed under publisher and/or the creator(s).

Journal Article

Backlog