Approaches to assessing the sexual behavior of male rats in the study of the effects of compounds that have a stimulating effect on sexual function

The paper presents a comparative analysis of information content of methods for assessing the copulatory behavior of male rats with the introduction of compounds that have a stimulating effect on the sexual activity of animals. The social significance of the problem of sexual dysfunctions determines the relevance of the development of various experimental models of sexual behavior that allow assessing the effectiveness and safety of new drug. The probability of detecting the activating effect of pharmacological agents on sexual activity directly depends on the correct choice of the experimental model. The drugs of the central mechanism of action – galantamine hydrobromide (1 mg/kg) and loxidan (1,7 mg/kg), were used as pharmacological agents; drugs of peripheral action were yohimbine hydrochloride (2,6 mg/kg) and vardenafil hydrochloride (1,7 mg/kg). It has been shown that the determination of the stimulating effects of compounds of the central mechanism of action is possible using methods with different testing duration (from 15 to 180 min). Thus, the introduction of galantamine enhances the sexual activity of males in terms of the «copulation rate», «the number of perfect ejaculations» and «the duration of the post-ejaculatory refractory period», loxidan – in terms of the «total number of intromissions» and «relative rest time» in tests of limited duration. In the test showing the completed sexual cycle of males, the stimulating effects of galantamine are shown in terms of «the number of completed copulatory series» and «the number of completed ejaculations». To assess the activating effects of compounds of the peripheral mechanism of action, the expediency of using experimental models with a test duration of 30 minutes or more was shown. The most informative test is the test of paired interaction between a male and a female until the male reaches the state of «sexual exhaustion». A method with high information content is presented, which provides a high probability of detecting the activating effect of compounds on the sexual function of male rats.

Determination of the stimulating effects of compounds of the central mechanism of action is possible using methods with different test duration