Dohanich G P, Daniel J M, Fader A J, Wolff S C, Gallogly P M, Overstreet D M
Department of Psychology, Tulane University, New Orleans, Louisiana 70118, USA.
Horm Behav. 1998 Apr;33(2):77-84. doi: 10.1006/hbeh.1998.1438.
Flinders Lines are two strains of rats selectively bred for their divergent physiological responses to cholinergic drug challenges. Flinders Sensitive Line (FSL) rats are highly sensitive to cholinergic stimulation of various autonomic and behavioral responses compared to Flinders Resistant Line (FRL) rats. Because cholinergic innervation contributes to the regulation of female sexual behaviors in rats, a study was conducted to compare the sexual responses of FSL females to those of FRL females, as well as to those of Long-Evans (LE) females, a conventional rat strain. Ovariectomized FSL rats exhibited significantly higher incidences of lordosis and proceptive behaviors than ovariectomized FRL and LE rats over a range of estrogen doses (2, 3, 4, 5, or 20 microgram(s)/kg estradiol benzoate at 48 h before testing) administered in combination with progesterone (1 or 2 mg/kg at 4-6 h before testing). In addition, the muscarinic antagonist scopolamine inhibited lordosis behavior strongly in FRL females over a range of doses (0.25, 0.5, 1, 2, or 4 mg/kg), but failed to inhibit lordosis in FSL females. Results indicate that FSL females are highly sensitive to the behavioral effects of gonadal steroids and highly insensitive to the effects of a muscarinic antagonist. The enhanced sexual behavioral responses of FSL females could be a consequence of their well-established cholinergic hypersensitivity or a consequence of other undocumented characteristics of FSL females such as hypersensitivity to ovarian hormones. FSL females could provide a valuable model for the study of estrogen action at behavioral, cellular, and molecular levels.
弗林德斯品系是两种经过选择性培育的大鼠品系，它们对胆碱能药物刺激具有不同的生理反应。与弗林德斯抗性品系（FRL）大鼠相比，弗林德斯敏感品系（FSL）大鼠对各种自主神经和行为反应的胆碱能刺激高度敏感。由于胆碱能神经支配有助于调节大鼠的雌性性行为，因此进行了一项研究，比较FSL雌性大鼠与FRL雌性大鼠以及常规大鼠品系长-伊文斯（LE）雌性大鼠的性反应。在一系列雌激素剂量（测试前48小时给予2、3、4、5或20微克/千克苯甲酸雌二醇）与孕酮（测试前4 - 6小时给予1或2毫克/千克）联合使用的情况下，去卵巢的FSL大鼠表现出比去卵巢的FRL和LE大鼠显著更高的脊柱前凸和接受性行为发生率。此外，毒蕈碱拮抗剂东莨菪碱在一系列剂量（0.25、0.5、1、2或4毫克/千克）下强烈抑制FRL雌性大鼠的脊柱前凸行为，但未能抑制FSL雌性大鼠的脊柱前凸行为。结果表明，FSL雌性大鼠对性腺类固醇的行为效应高度敏感，对毒蕈碱拮抗剂的效应高度不敏感。FSL雌性大鼠增强的性行为反应可能是其已确立的胆碱能超敏反应的结果，或者是FSL雌性大鼠其他未记录特征（如对卵巢激素超敏）的结果。FSL雌性大鼠可为在行为、细胞和分子水平研究雌激素作用提供有价值的模型。
