Schillo K K, Green M A, Hayes S H
Department of Animal Sciences, University of Kentucky, Lexington 40546-0215.
J Reprod Fertil. 1988 May;83(1):431-8. doi: 10.1530/jrf.0.0830431.
Finnish Landrace x Southdown ewes were ovariectomized (OVX) and subjected to daily photoperiods of 16L:8D (Group I) or 8L:16D (Group II) for 84 days. Ewes were then either adrenalectomized (ADX) (N = 5 for Group I; N = 4 for Group II) or sham ADX (N = 6 for Groups I + II). After surgery, ewes in Group I were subjected to 8L:16D for 91 days and 16L:8D for 91 days whereas ewes in Group II were exposed to 16L:8D for 91 days and 8L:16D for 91 days. Oestradiol implants were inserted into all ewes on Day 148. Sequential blood samples were taken at 28, 56, 91, 119, 147 and 168 days after surgery to determine secretory profiles of LH and prolactin. Photoperiod did not influence LH release in Group I in the absence of oestradiol. Although photoperiod influenced frequency and amplitude of LH pulses in Group II before oestradiol treatment, adrenalectomy did not prevent these changes in patterns of LH release. However, in Group II the increase in LH pulse amplitude during exposure to long days was greater (P less than 0.01) in adrenalectomized ewes than in sham-operated ewes. Mean concentrations of LH increased in ADX ewes on Days 91 (P = 0.07) and 119 (P less than 0.05). Adrenalectomy failed to influence photoperiod-induced changes in mean concentrations of LH, amplitude of LH pulses and frequency of LH pulses in the presence of oestradiol. Concentrations of prolactin were influenced by photoperiod. In Groups I and II concentrations of prolactin increased (P less than 0.01) after adrenalectomy, but the magnitude of this effect decreased over time.(ABSTRACT TRUNCATED AT 250 WORDS)
芬兰长白猪与南丘羊的杂交母羊接受卵巢切除术（OVX），并在84天内分别接受16小时光照：8小时黑暗（第一组）或8小时光照：16小时黑暗（第二组）的每日光照周期。然后，母羊要么接受肾上腺切除术（ADX）（第一组N = 5；第二组N = 4），要么接受假肾上腺切除术（第一组和第二组N = 6）。手术后，第一组母羊先接受8小时光照：16小时黑暗91天，再接受16小时光照：8小时黑暗91天，而第二组母羊先接受16小时光照：8小时黑暗91天，再接受8小时光照：16小时黑暗91天。在第148天，所有母羊都植入了雌二醇。在手术后第28、56、91、119、147和168天采集系列血样，以测定促黄体生成素（LH）和催乳素的分泌情况。在没有雌二醇的情况下，光照周期对第一组的LH释放没有影响。虽然光照周期在雌二醇治疗前影响了第二组LH脉冲的频率和幅度，但肾上腺切除术并未阻止LH释放模式的这些变化。然而，在第二组中，肾上腺切除的母羊在暴露于长日照期间LH脉冲幅度的增加比假手术母羊更大（P小于0.01）。在第91天（P = 0.07）和119天（P小于0.05），ADX母羊的LH平均浓度增加。在有雌二醇的情况下，肾上腺切除术未能影响光照周期诱导的LH平均浓度、LH脉冲幅度和LH脉冲频率的变化。催乳素浓度受光照周期影响。在第一组和第二组中，肾上腺切除术后催乳素浓度增加（P小于0.01），但这种影响的程度随时间降低。（摘要截取自250字）
