Evaluation of physiologic pain in relation to pain substances in healthy subjects

John Onimisi Ogedengbe; Alexander Babatunde Adelaiye; Aliyu Mohammed; Joseph Olusegun Ayo; Augustine Nonso Odili; Olusoji Matthew Adeyemi; Stella Akeju; Philomina Peter

doi:10.1016/j.pathophys.2015.08.001

Evaluation of physiologic pain in relation to pain substances in healthy subjects

Pathophysiology. 2015 Dec;22(4):183-7. doi: 10.1016/j.pathophys.2015.08.001. Epub 2015 Aug 22.

Authors

John Onimisi Ogedengbe¹, Alexander Babatunde Adelaiye², Aliyu Mohammed³, Joseph Olusegun Ayo⁴, Augustine Nonso Odili⁵, Olusoji Matthew Adeyemi⁶, Stella Akeju⁷, Philomina Peter⁸

Affiliations

¹ Department of Human Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, University of Abuja, Abuja 901001, Nigeria; Department of Human Physiology, Faculty of Medicine, Ahmadu Bello University, Zaria 810000, Nigeria. Electronic address: john.ogedengbe@uniabuja.edu.ng.
² Department of Human Physiology, Faculty of Basic Medical Sciences, College of Health Sciences, University of Abuja, Abuja 901001, Nigeria; Department of Human Physiology, Faculty of Medicine, Ahmadu Bello University, Zaria 810000, Nigeria. Electronic address: adelaiye@yahoo.co.uk.
³ Department of Human Physiology, Faculty of Medicine, Ahmadu Bello University, Zaria 810000, Nigeria. Electronic address: amohammed@abu.edu.ng.
⁴ Department of Veterinary Physiology, Ahmadu Bello University, Zaria 810000, Nigeria,. Electronic address: ayojo94@yahoo.com.
⁵ Department of Internal Medicine, Faculty of Clinical Sciences, College of Health Sciences, University of Abuja, Abuja 901001, Nigeria. Electronic address: odilimercy@yahoo.com.
⁶ Department of Medical Laboratory Sciences, University of Abuja Teaching Hospital, Abuja 901001 Nigeria. Electronic address: sojibilly@gmail.com.
⁷ Department of Medical Laboratory Sciences, University of Abuja Teaching Hospital, Abuja 901001 Nigeria. Electronic address: dankol4b@yahoo.co.uk.
⁸ Department of Medical Laboratory Sciences, University of Abuja Teaching Hospital, Abuja 901001 Nigeria. Electronic address: omoikephilomina@gmail.com.

PMID: 26323369
DOI: 10.1016/j.pathophys.2015.08.001

Abstract

This study was aimed at finding a relationship between pain modulators in the blood and physiological pain in apparently healthy Nigerians. It also aimed at establishing a pilot study for finding reference values for plasma levels of substance P, serotonin and tryptophan for the first time among Nigerians. Volunteers were made up of 110 residents of Abuja, aged between 21 and 50 years. Cold pressor test was used to induce pain assessing pain intensity, threshold and tolerance. ELISA was used to assay for plasma substance P, serotonin and tryptophan. Pain parameters from cold pressor test were correlated with plasma pain modulators measured. Results from cold pressor test revealed pain intensity to be 5.79±0.25cm, pain threshold 28.77±2.32s and pain tolerance 143.62±24.39s. Blood plasma level of substance P was 116.52±20.53pg/mL, serotonin 454.18±30.16ng/mL and tryptophan 12.77±0.67μg/mL. There was negative correlation between pain threshold and plasma substance P, pain tolerance and plasma substance P and pain threshold and plasma serotonin. There was however a positive correlation between pain intensity and plasma serotonin. In conclusion, the regression formulas may aid in using cold pressor test to predict blood substance levels of the measured pain modulators in a low resource setting like Nigeria where ELISA test is very expensive.

Keywords: Pain intensity; Pain threshold; Pain tolerance; Serotonin; Substance P.