Study of the effects of kisspeptin analogs on the behavior of<i> Danio rerio</I>

Abstract

The neuropeptide kisspeptin is currently most widely known as a regulator of mammalian sexual behavior. For pharmacological analysis, mammalian Kiss1 kisspeptin analogues were used, Clone (USA): KS4, KS5, KS6, KS7, KS8, KS9 and Kiss 10. Kisspeptins were dissolved in aquarium water and applied in two doses: 1). 0.01 mg per 1000 ml of water; 2). 0.1 mg per 1000 ml of water. Phenazepam was dissolved in water and used in three doses: 1) 0.1 mg per 1000 ml of water; 2) 0.5 mg per 1000 ml of water; 3) 1 mg per 1000 ml of water. This paper compares kisspeptines with anxiolytics using phenazepam as an example in the novelty test. It was shown that in response to the novelty of being placed in the viewing tank, fish responded by diving to the bottom, increasing freesing, and decreasing the number of movements to the upper half of the tank. Fish residence time in the lower part of the tank after administration of phenazepepam decreased, especially when used at a dose of 0.5 and 1 mg/liter. Kisspeptin analogues decreased the indices characterizing the anxious state of the fish. Against the background of Kiss1 kisspeptin analogues, the average fish path length differed significantly in contrast to the effects of phenazepam. KS 4 at a dose of 0.1 mg/L showed a 1.4-fold decrease in the number of freesing, 1.4-fold decrease in the freesing time and 1.4-fold decrease in the trajectory length. The number of transitions to the upper part of the tank increased 1.5 times. The dose of 0.01 mg/l decreased the number of freesing by 1.5 times, freesing time by 1.5 times, trajectory length by 3 times. KS 5 at a dose of 0.1 mg/L decreased the number of freesings by a factor of 1.6, the freesing time by a factor of 1.6, and the trajectory length by a factor of 1.17. The number of transitions to the upper part of the tank increased 1.5 times. The dose of 0.01 mg/l decreased the number of freesing by 3 times, freesing time by 2.8 times, trajectory length by 2.8 times. KS 6 at a dose of 0.1 mg/l decreased the number of freesings by 2.7 times, the freesing time by 2 times, and the trajectory length by 2.5 times. The number of transitions to the upper part of the aquarium increased 2.5 times. The dose of 0, 01 mg/ml decreased the number of freesing by 2.6 times, freesing time by 2.6 times, trajectory length by 1.7 times. KS 7 at a dose of 0.1 mg/L decreased the number of freesing by a factor of 1.7, freesing time by a factor of 1.4, and trajectory length by a factor of 1.3. The number of movements to the top of the aquarium increased 1.6-fold. The dose of 0.01 mg/l decreased the number of freesing by 1.7 times, freesing time by 1.4 times, trajectory length by 1.6 times. KS8 at a dose of 0.1 mg/L decreased the number of freesings by 1.6 times, the freesing time by 1.7 times, and the trajectory length by 1.6 times. The dose of 0.01 mg/l decreased the number of freesing by 2.3 times, the freesing time by 2.2 times, and the trajectory length by 1.8 times. KS9 at a dose of 0.1 mg/l decreased the number of freesing by 2.2 times, the freesing time by 2.2 times, and the trajectory length by 1.2 times. The dose of 0.01 mg/L reduced the number of freesings by 1.5 times, the freesing time by 1.5 times, and the trajectory length by 1.6 times. In Kiss 10 at a dose of 0.1 mg/L, there was a 1.6-fold decrease in the number of frizzings, a 1.5-fold decrease in freezing time, and a 1.4-fold decrease in trajectory length. There was a 2.7-fold increase in the transitions to the upper part of the aquarium. The dose of 0.01 mg/l decreased the number of freesing by 1.7 times, freesing time by 1.6 times, trajectory length by 1.3 times. We observed a 1.3-fold increase in the number of trajectories. Summarizing the obtained indicators, we came to the conclusion that kisspeptin analogues were not inferior in their effect to the effects obtained after taking the tranquilizer phenazepam. Among mammalian kisspeptin analogues, KS6 at a dose of 0.1 mg/L showed the best performance. It is concluded that mammalian Kiss1 kisspeptin analogues and Kiss 10 reduce anxiety-phobic reactions to novelty in Danio rerio. At the same time, the effects of the studied kisspeptin analogues are lower than those of phenazepam. Kisspeptin is involved not only in the modulation of 5-HT-dependent behavior in Danio rerio, but also in the GABA-ergic system as benzodiazepine-type tranquilizers. The results support the hypothesis that kisspeptin may be involved in the regulation of anxiety-phobic states, apparently to maintain the emotional aspects of reproductive behavior, such as sexual motivation and arousal.