Effect of Melatonin Treatment on the CD4 + Count of Adult Male Rabbits

Abstract

The effect of melatonin treatment on the CD₄⁺ count of six adult male rabbits injected subcutaneously with 100ug/ 100g body weight at the end of the light phase (1½ hrs before light went off) daily for 60 days and four controls which received ethanol/saline solution was investigated. Whole blood was collected from the rabbits through cardiac puncture into EDTA anticoagulant and CD₄⁺ enumeration was done using the Dynal beads method (Dynal Asa Oslo, Norway), an alternative technique to flow cytometry for the quantification of human peripheral blood CD₄⁺ T- cells in resource-limited setting. Results obtained showed that there was a significant increase from 140.00 + 2.45/μl to 160.00 + 1.41/μl in the melatonin treated rabbits (P<0.05). It was concluded that melatonin associated increase in the production of CD₄⁺ in the exposed rabbits is suggestive of immune enhancement.