| Project/Area Number |
12670068
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Environmental physiology (including Physical medicine and Nutritional physiology)
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| Research Institution | Nippon Medical School |
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Principal Investigator |
KONDO Yasuhiko Nippon Medical School, Dept. of Physiology, Research Associates, 医学部, 助手 (00192584)
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| Project Period (FY) |
2000 – 2002
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| Project Status |
Completed (Fiscal Year 2002)
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| Budget Amount *help |
¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 2002: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2001: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2000: ¥1,200,000 (Direct Cost: ¥1,200,000)
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| Keywords | Sexual Motivation / Copulatory Pacing / Sexual Preference / Estrogen / Medial Amygdala / Medial Preoptic Area / Lateral Septum / Female Rat / 性行動 / 動機づけ / 情動 / 性ホルモン / 扁桃体 / 大脳辺縁系 / ラット |
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| Research Abstract |
In this project, we investigated the neuroendocrine mechanisms of sexual motivation in female rats by means of two behavioral test paradigms, paced mating (mating test with an escapable place for females) and partner preference (females prefer odors of sexually active males rather than those of inactive one). Radiofrequency lesions in the medial amygdala eliminated partner preference and shortened latency to access sexual males in paced mating test. In contrast, medial preoptic lesions eliminated partner preference without effect on pacing behavior, whereas lateral septal lesions made their pace faster but did not affect partner preference. These results suggest that the forebrain structures that have been known to control lordosis may play different roles in the regulation of sexual motivation in female rats.
Secondly, we examined effects of gonadal steroids on preference of conspecific odors in male and female rats. Sexual active males preferred odors of receptive females rather than those of males and ovariectomized females (masculine pattern), while estrous females preferred odors of sexually active males than those of females and orchidectomized males (feminine pattern). Gonadectomy in both males and females eliminated all the preference. Although treatment with testosterone to castrated females restored the feminine pattern of preference, treatment of estrogen and progesterone to castrated males activated the feminine pattern, but not the masculine pattern, of preference. These suggest that the masculine pattern of preference is regulated by androgen, whereas the feminine pattern is regulated by estrogen and/or progesterone. No transsexual pattern appeared after androgen treatment in females suggests that normal females have no neural circuits for the masculine pattern because of a lack of androgen exposures in their perinatal periods. Further studies are required to elucidate this mechanism.
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