- 著者
- Yui SHIMOMI Yasuhiko KONDO
- 出版者
- Japanese Association for Laboratory Animal Science
- 雑誌
- Experimental Animals (ISSN:13411357)
- 巻号頁・発行日
- pp.19-0161, (Released:2020-06-30)
- 被引用文献数
- 3
Among the intact male rats, a subpopulation has been found to show little or no sexual behavior, even after experiencing several mating sessions. This study investigated whether sexually sluggish (SS) males show behavioral differences from normal copulatory (NC) males, other than those concerning sexual behavior. The olfactory preference of males was measured through the time spent displaying nose-poking behavior directed at sexually active males and estrous females for odor exploration in a three-chamber apparatus. Both the NC and SS males showed a significant preference for the odor of estrous females compared with that of male odors. However, SS males spent significantly less time nose-poking estrous females than NC males. The food-finding test was performed after overnight fasting. Our findings showed that all the NC males found the buried pellet within 5 min, whereas over 60% of the SS males failed to find it. The males were also tested for their ability to find a buried bag containing soiled bedding from estrous female cages. The bag was found by 80% of NC males, but only by 20% of SS males. Our results suggest that SS and NC male rats differ not only in sexual behavior but also in other functions such as olfaction.
- 著者
- Yasuhiko Kondo Yasuo Sakuma
- 出版者
- THE PHYSIOLOGICAL SOCIETY OF JAPAN
- 雑誌
- The Japanese Journal of Physiology (ISSN:0021521X)
- 巻号頁・発行日
- pp.0601160021, (Released:2006-01-17)
- 被引用文献数
- 19 29
Partner preference and paced mating tests were accomplished in ovariectomized female rats following bilateral radiofrequency lesions in the medial amygdala. Open field behavior and passive avoidance learning were also examined to investigate the underlying behavioral mechanism. Partner preference was determined in a chamber located between castrated and sexually active males. Airborne olfactory cues were presented to the female through small holes on the partition. The lesion diminished preference for the odor of sexually active males over that of castrated males, even after injection with high-dose of estrogen. On the other hand, in a paced mating test, the lesioned females without estrogen treatment showed a significantly shorter latency for entering the male's compartment in a two-compartment apparatus, which allowed the females, but not the males, to cross the barrier through a narrow opening at the bottom. However, administration of estrogen and progesterone reduced the effect. The lesion had no effect on emotionality or exploratory behavior in an open field test, but impaired passive avoidance learning capability. We suggest that a male poses an inherent threat to a female. The seemingly incompatible results of partner preference and paced mating tests can be compromised if the male is inherently aversive to the female; this emotional response can be removed by the medial amygdala lesion.