The influnce of oxytocin on the central nervous system by different routes of administration

Abstract

Background. One of the unresolved problems on the way to improving the pharmacotherapy of CNS diseases is the development and creation of technologies that allow drugs to cross the blood-brain barrier (BBB). One way to bypass the blood-brain barrier is to use the intranasal route of administration. Delivery of the drug is carried out due to the peculiarities of the mechanism of transport of substances.
 Aim. To study the effect of intranasal administration of oxytocin on the behavior of mice and its content in various brain structures.
 Materials and methods. The study used 60 outbred mice divided into 6 groups. The first group of mice were intact and did not present with oxytocin or physiological solution. The second and third groups of mice found a single injection of 20 and 300 l of oxytocin 5 IU intraperitoneally, respectively. The fourth group of mice was injected intranasally with oxytocin 5 IU in an amount of 20 l. The fifth group of mice received 20 l of saline intranasally and the sixth group of mice received 300 l of saline intraperitoneally. Behavioral effects were recorded in the elevated plus maze for 5 min, the duration of stay in the open arm, the number of transitions between the arms, and the number of hangings from the arms were assessed. Then measured the concentration of oxytocin in the following structures: olfactory bulb, striatum, hypothalamus and hippocampus using enzyme immunoassay.
 Results. Intranasal administration of oxytocin causes changes in behavior in mice, in particular, a decrease in the degree of anxiety (anxiolytic effect). When timing the open arms in the plus maze test, it was found that mice administered intranasal oxytocin required more time spent in the arms (32.444.28 s versus the control group with a value of 5.661.96 s). ), the number of transitions between the sleeves increased (1.900.10 s versus 1.100.10 s in the control group) and the number of hangings from the sleeves (8.441.37 versus 3.770.98 in the control group). There was an increase in one of the indicators - the number of hanging from the sleeve after intraperitoneal injection of 300 l of oxytocin, which may indicate the manifestation of an anxiolytic effect of oxytocin. The remaining groups: intranasal saline injection, intraperitoneal saline injection, intraperitoneal injection of 20 l of oxytocin did not show significant changes in behavior compared with the control group. In addition, it was found that after intranasal administration of oxytocin, its content increased in certain brain structures the hypothalamus and hippocampus.
 Conclusion. The results of this study indicate the potential efficacy of intranasal administration of oxytocin in the treatment of diseases affecting the central nervous system.