Barb C R, Barrett J B, Rampacek G B, Kraeling R R
United States Department of Agriculture, Agricultural Research Service, Athens, GA 30613.
Life Sci. 1993;53(14):1157-64. doi: 10.1016/0024-3205(93)90552-e.
Administration of n-methyl-d, l-aspartate (NMA) to pigs in vivo increased GH and suppressed LH secretion. Cultures of anterior pituitary cells from pigs in the follicular phase (FOL; n = 3) and luteal phase (LUT; n = 3) of the estrous cycle, and ovariectomized (OVX; n = 10) pigs were treated with NMA (10(-4), 10(-6) or 10(-8) M) or the NMA antagonist, 2-amino-5-phosphonopentanoic acid (AP5; 10(-4), 10(-6) or 10(-8) M), to determine if NMA affects the pituitary directly. Secreted LH and GH were measured at 4 h after treatment. Basal LH and GH secretion (control; C) were 1.1 +/- 0.6, 4.4 +/- 2.1 and 5.6 +/- 1.3 ng/well and 5.2 +/- 1.2, 7.5 +/- 1.2 and 5.2 +/- 1.7 ng/well for FOL, LUT and OVX, respectively. Relative to C, 10(-4) M NMA increased (P < 0.001) LH secretion 2.4-, 2.2- and 5.1-fold in FOL, LUT and OVX cultures, respectively. The effect of 10(-4) M NMA was inhibited by 10(-4) M AP5 (P < 0.05) in FOL cultures, but not in OVX cultures. GnRH increased (P < 0.001) LH levels 3.1-, 2.3- and 3.8-fold in FOL, LUT and OVX cultures, respectively. Relative to C, 10(-4), 10(-6) and 10(-8) M NMA increased (P < 0.03) GH secretion 1.5-, 1.5- and 2.3-fold in LUT and 1.7-, 2.3- 2.0-fold in OVX cultures, respectively. AP5 alone or in combination with NMA failed to alter basal GH secretion.(ABSTRACT TRUNCATED AT 250 WORDS)
给猪体内注射N-甲基-D，L-天冬氨酸（NMA）可增加生长激素（GH）分泌并抑制促黄体生成素（LH）分泌。对处于发情周期卵泡期（FOL；n = 3）和黄体期（LUT；n = 3）的猪以及去卵巢（OVX；n = 10）的猪的垂体前叶细胞培养物，用NMA（10⁻⁴、10⁻⁶或10⁻⁸ M）或NMA拮抗剂2-氨基-5-磷酸戊酸（AP5；10⁻⁴、10⁻⁶或10⁻⁸ M）处理，以确定NMA是否直接影响垂体。在处理后4小时测量分泌的LH和GH。FOL、LUT和OVX的基础LH和GH分泌（对照；C）分别为1.1±0.6、4.4±2.1和5.6±1.3 ng/孔以及5.2±1.2、7.5±1.2和5.2±1.7 ng/孔。相对于C，10⁻⁴ M NMA分别使FOL、LUT和OVX培养物中的LH分泌增加（P < 0.001）2.4倍、2.2倍和5.1倍。在FOL培养物中，10⁻⁴ M AP5抑制了10⁻⁴ M NMA的作用（P < 0.05），但在OVX培养物中未观察到抑制作用。促性腺激素释放激素（GnRH）分别使FOL、LUT和OVX培养物中的LH水平增加（P < 0.001）3.1倍、2.3倍和3.8倍。相对于C，10⁻⁴、10⁻⁶和10⁻⁸ M NMA分别使LUT培养物中的GH分泌增加（P < 0.03）1.5倍、1.5倍和2.3倍，使OVX培养物中的GH分泌增加1.7倍、2.3倍和2.0倍。单独使用AP5或与NMA联合使用均未改变基础GH分泌。（摘要截断于250字）
