Effect of Oxytocin on the Emotional State and Behavior of Rats under Stress Conditions

Abstract

Oxytocin, a hormone exerting controlling effects on lactation, sexual and maternal behavior, and cyclic organization of sleep and wakefulness, is capable of significantly modulating reactions of the organism to the action of stressogenic stimuli. We studied the effects of injections of synthetic oxytocin on the behavioral phenomena and emotional state of rats during realization of a proconflict test induced by "punishments" (nociceptive electrical stimuli) in the process of drinking after water deprivation. Intraperitoneal injections of oxytocin in a 4.0 µg dose resulted in shortening of the delays of coming of rats to a water dish and also in an increase in the number of drinks of water punished by electrical stimulation, as compared with the corresponding indices in control animals. After oxytocin injections, the intensity of research activity of rats in the open field, in general, increased. After realization of the proconflict test, locomotor and orientational/ research activities in animals preliminarily injected with oxytocin were much more intense than those in control rats (in the latter ones, these activities were sharply suppressed). Injections of oxytocin also led to certain normalization of the emotional state; after the proconflict test, negative shifts in this state in control rats were obvious. Therefore, oxytocin appreciably increases the resistivity of the organism against stress.

Effect of Suckling Systems on Serum Oxytocin and Cortisol Concentrations and Behavior to a Novel Object in Beef Calves

“…Oxytocin (OT) has recently received attention as a positive indicator of pleasure of livestock, one of the most important aspects of animal welfare ( Broom and Fraser, 2007 ). It was reported that OT injections after a stress test induced normalization of the emotional state in rats ( Svanidze et al, 2012 ). In humans, OT reduced activation of the amygdala, a central component of fear neurocircuity ( Kirsch et al, 2005 ).…”

Serum Oxytocin in Cows Is Positively Correlated with Caregiver Interactions in the Impossible Task Paradigm

“…Increased stress responses were recorded in mice lacking the OXT gene during maze exploration [36] and a similar result was observed after intranasal OXT administration during a social isolation test in ewes [37]. OXT mediates the stress responses in the presence of social partners (social buffering) [38]; also, synthetic OXT administration helps to normalize the emotional state from a stressful event, favoring the recovery of normal behaviors [39]. It has been hypothesized that OXT may cause endocrine changes in the activity of the hypothalamus-pituitary-adrenal axis by acting as a key modulator of anxiety-related behaviors (reviewed in [40]) and several studies have reported the involvement of OXT in the control of social stress by reducing the cortisol response [41][42][43][44].…”

Role of oxytocin in improving the welfare of farm animals — A review

“…These results are supported by those of Dhakar et al [ 24 ], who showed that OT-receptor knockout rats performed exhibited aggressive behavior than intact animals. Further, centrally administered OT also induced grooming behavior in male rats [ 25 ], affiliative response of huddled sitting in the subordinate squirrel monkey [ 26 ], and flexible behaviors such as locomotors activity in the open field under stress condition [ 27 ].…”