Jones S L, Cordeaux E, Germé K, Pfaus J G
Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC H4B 1R6, Canada.
Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montreal, QC H4B 1R6, Canada.
Horm Behav. 2015 Jul;73:104-15. doi: 10.1016/j.yhbeh.2015.07.002. Epub 2015 Jul 8.
Exposure to testosterone during a critical period of prenatal development disrupts the normal display of sexual behaviors in adult ovariectomized (OVX) rats treated with estradiol benzoate (EB) followed by progesterone (P). The organizational hypothesis posits that prenatally androgenized females (PNAFs) are desensitized to EB. We tested this hypothesis by first treating PNAFs with varying doses of EB (2.5, 5, 10, 20μg) followed by P (500μg), and second by subjecting females to an established EB behavioral sensitization paradigm where females are first given sexual experience with EB (10μg) and P prior to repeated sexual behavior testing with EB alone. Long-Evans females were androgenized in utero by a s.c. injection of 500μg testosterone propionate or the oil control to pregnant dams on gestational day 18. Female offspring were OVX on postnatal day 80 and tested one week later in the unilevel 4-hole pacing chamber. Genital tissue was defeminized in PNAFs, and the lordosis quotient (LQ) and partial (i.e., hops/darts) and full solicitations were significantly lower, while defensive behaviors were higher, in PNAF females, relative to non-PNAF females regardless of the acute EB priming dose. However, repeated testing with EB alone (10μg), or EB and P eliminated the differences between groups on LQ and hops/darts, indicating that the behavioral deficit can be overcome by sexual experience. These results suggest that PNAFs are not desensitized to EB, and despite disruptions in sexual differentiation of anatomical structures, the deficiency in sexual behavior in response to acute EB and P can be experientially overcome. PNAFs appear, however, to have a chronic deficit in the expression of full solicitations.
在产前发育的关键时期接触睾酮，会扰乱成年去卵巢（OVX）大鼠的正常性行为表现。这些大鼠先用苯甲酸雌二醇（EB）处理，随后用孕酮（P）处理。组织学假说认为，产前雄激素化的雌性大鼠（PNAF）对EB不敏感。我们通过以下方式验证这一假说：首先用不同剂量的EB（2.5、5、10、20μg）处理PNAF，随后用P（500μg）处理；其次，让雌性大鼠接受既定的EB行为敏化范式，即雌性大鼠先用EB（10μg）和P进行性体验，然后单独用EB进行重复性性行为测试。在妊娠第18天，给怀孕的Long-Evans雌性大鼠皮下注射500μg丙酸睾酮或油剂作为对照，使其子宫内雄激素化。雌性后代在出生后第80天进行卵巢切除，并在一周后在四级单孔起搏室进行测试。与非PNAF雌性大鼠相比，无论急性EB启动剂量如何，PNAF雌性大鼠的生殖组织均出现去雌性化，其脊柱前凸商（LQ）、部分（即跳跃/冲刺）和完全求偶行为显著降低，而防御行为则更高。然而，单独用EB（10μg）或EB与P重复测试消除了两组在LQ和跳跃/冲刺方面的差异，表明性行为经验可以克服行为缺陷。这些结果表明，PNAF对EB并不不敏感，尽管解剖结构的性分化受到干扰，但急性EB和P引起的性行为缺陷可以通过经验克服。然而，PNAF在完全求偶行为的表达上似乎存在慢性缺陷。
