The Usefulness of Non-contact Erection Observation for Evaluation Sexual Function in Male Rat / 대한비뇨기과학회지

ABSTRACT

PURPOSE: Evaluation of sexual function is an important step for animal studies about sexual function. Male rats could display penile erection in the presence of an inaccessible estrous female. We examined the usefulness of observing non-contact erection (NCE) for the evaluation of sexual function in male rats. MATERIALS AND METHODS: Forty five Long-Evans male rats (8 weeks old) were used in this study. Tests for NCE were conducted in a glass chamber divided in half by 2 wire-mesh screens that prevented direct contact, but the rats freely passed other forms of stimulation. If at least 1 NCE could be observed during 45 minutes, we considered this as a positive response. In case of two or three positive responses in three NCE tests, that was considered as NCE (+). After NCE, copulation observations were noted to evaluate sexual function. If at least two ejaculations could be observed during 45 minutes, we considered that a positive response. In case of two or three positive responses in three copulation observations, that was considered as normal sexual function. RESULTS: Twenty one of 45 male rats (47%) were NCE (+) and 34 of 45 male rats (76%) had normal sexual function. In 21 NCE (+) rats, 20 rats had normal sexual function: only one was impotent. The positive predictive value of the NCE observation for the evaluation of sexual function was 95%. In 11 impotent rats, 10 rats were NCE (-). The specificity of the NCE observation was 91%. CONCLUSIONS: These results indicated that NCE observation could be a useful method for evaluating the sexual function of male rat.