翻訳と辞書 Words near each other ・ Organizational project management ・ Organizational Research Methods ・ Organizational retaliatory behavior ・ Organizational safety ・ Organizational space ・ Organizational storytelling ・ Organizational structure ・ Organizational structure of Jehovah's Witnesses ・ Organizational structure of the Central Intelligence Agency ・ Organizational structure of the United States Department of Defense ・ Organizational studies ・ Organizational Systems Security Analyst ・ Organizational technoethics ・ Organizational theory ・ Organizational unit (computing) ・ Organizational-Activational Hypothesis ・ Organizational-dynamic game ・ Organizationally unique identifier ・ Organizations in MacGyver ・ Organizations of Alias ・ Organizations of the Dune universe ・ Organizations of the Iranian Revolution ・ Organization–public relationships ・ Organizatsia na Bulgarskite Skauty ・ Organizatsiya Ukraïns'kykh Skautiv ・ Organização Mineira de Transportes Aéreos ・ Organizações Paulo Octávio ・ Organizația Națională a Scouților din Moldova ・ ORGANIZE ・ Organize-it Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Organizational-Activational Hypothesis ： ウィキペディア英語版 Organizational-Activational Hypothesis The Organizational-Activational Hypothesis states that steroid hormones permanently organize the nervous system during early development, which is reflected in adult male or female typical behaviors.〔 Phoenix CH, Goy RW, Gerall AA, Young WC. Organizing action of prenatally administered testosterone propionate on the tissues mediating mating behavior in the female guinea pig. Endocrinology. 1959;65:369–382. 〕 In adulthood, the same steroid hormones activate, modulate, and inhibit these behaviors. 〔 Nelson, R. An Introduction to Behavioral Endocrinology (4th ed.). Sunderland, Mass.: Sinauer Associates. 1995. Print.〕 This idea was revolutionary when first published in 1959 because no other previous experiment had demonstrated that adult behaviors could be determined hormonally during early development. 〔 Wallen, Kim. “The Organizational Hypothesis: Reflections on the 50th anniversary of the publication of Phoenix, Goy, Geral, and Young (1959).” Hormones and Behavior. 561. Web. 24 Mar. 2015. 〕 The Phoenix et al. study sought to discover whether gonadal hormones given during the prenatal period had organizing effects on guinea pigs’ reproductive behavior〔 Phoenix CH, Goy RW, Gerall AA, Young WC. Organizing action of prenatally administered testosterone propionate on the tissues mediating mating behavior in the female guinea pig. Endocrinology. 1959;65:369–382. 〕 It was found that when female controls, gonadectomized (removal of gonads) females, hermaphrodites, and castrated males were injected prenatally with testosterone proprionate, the mean number of mounts increased. This increase in male-typical reproductive behavior shows that prenatal androgens have a masculinizing effect. Moreover, the organizing effects of hormones can have permanent effects. Phoenix et al. found that females injected with testosterone propionate while pregnant, instead of neonatally, did not have any effect on lordosis. This demonstrates that when testosterone is given postnatally in females, there may not be lasting effects as compared to prenatally administered testosterone. The data from this study supports the organizational hypothesis that states when androgens are given prenatally there is an organizing effect on sexual behavior, permanently altering normal female mating behavior as adults. 〔 Phoenix CH, Goy RW, Gerall AA, Young WC. Organizing action of prenatally administered testosterone propionate on the tissues mediating mating behavior in the female guinea pig. Endocrinology. 1959;65:369–382. 〕 == Mechanisms in sexual differentiation == Sexual behavior in rats is organized prenatally and activated with steroids hormones in adulthood. 〔 Nelson, R. An Introduction to Behavioral Endocrinology (4th ed.). Sunderland, Mass.: Sinauer Associates. 1995. Print.〕 In males high levels of testosterone produced by testes and travel to the brain. Here, testosterone is aromatized to an estradiol and masculinizes and defeminizes the brain. Thus, estradiol is responsible for many male-typical behavior. In females, the ovaries produce large amounts of estrogen during gestation. Rats have alpha-fetoprotein that binds to the estrogen before it can reach the brain. The estrogen is eventually metabolized in the liver. This protein has a low affinity for androgens. Therefore, testosterone can reach the brain without being taken up by alpha-fetoprotein. Due to fact that males have different levels of androgens in the brain, this can lead to organizing effects from androgen exposure with the expression of masculine behavior. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Organizational-Activational Hypothesis」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.