Högskolan i Skövde

Background: Vasopressin and Oxytocin both act as neurotransmitters and hormones. This report is a part of an original study that aimed to investigate how the endogenous release of nonapeptides was affected by caress-like touch from a beloved partner and an unfamiliar male in healthy females by analysing plasma samples collected during the touch-experiment. In this part, the same plasma samples were analysed for the release of vasopressin, with a hypothesis that the touch of an unfamiliar male would induce higher levels of vasopressin.

Method: Plasma samples were extracted and analysed with a ELISA kit provided by Enzo Life Sciences. The data from these readings were later analysed with unpaired and paired T-tests.

Results and discussion: A significant increase of vasopressin levels was detected by the partners touch among those who received the touch in the order: stranger first, partner second (p=0,0044). Which imply a contradictory increase of vasopressin to the hypothesis. The same order also produced higher oxytocin release (p=0,007), suggesting a co-release of the two nonapeptides. Without reaching significance, a weak tendency of higher vasopressin levels induced by the touch of stranger was found.  A correlational measurement indicate that oxytocin possibly can suppress the release of vasopressin.

Conclusion: The findings show that vasopressin and oxytocin share complex interactions, and that oxytocin might have a suppressive effect on vasopressin release. However, the original design of this study was focused on stimulating oxytocin release. Thus, the caress-like touch may not be enough to induce a sufficient vasopressin excretion to, further investigations designed to focus on vasopressin release is therefore of interest.