Bergendahl M, Huhtaniemi I
Department of Physiology, University of Turku, Finland.
Am J Physiol. 1993 May;264(5 Pt 1):E717-22. doi: 10.1152/ajpendo.1993.264.5.E717.
Effects of short-term fasting (3-4 days) on pituitary-testicular functions were studied during sexual maturation in male rats at 25, 35, 45, 55, and 65 days of age. Among the main findings, testicular testosterone decreased by 41-68% at all ages (P < 0.01-0.05). The pituitary steady-state mRNA levels of the common alpha-subunit (28-55%) and follicle-stimulating hormone (FSH) beta-subunit (25-50%) decreased (P < 0.01-0.05) at 25, 55, and 65 days of age but not at 35 and 45 days; the luteinizing hormone (LH) beta-subunit did not respond at any age. Fasting decreased serum LH (P < 0.01) at 25, 55, and 65 days of age but not at 35 and 45 days. Likewise, fasting decreased pituitary and/or serum FSH only in the 25- and 65-day-old rats (P < 0.01-0.05). In conclusion, LH and FSH secretion, and the gene expression of common alpha- and FSH beta-subunits, decreased consistently during short-term fasting only in prepubertal (25 days) and adult (65 days) but not in peripubertal animals (35 and 45 days). Hence, the pubertal rise in gonadotropins represents such a strong positive induction that it largely overrides the antigonadotropic effect of fasting.
研究了短期禁食（3 - 4天）对25、35、45、55和65日龄雄性大鼠性成熟过程中垂体 - 睾丸功能的影响。主要研究结果如下：在所有年龄段，睾丸睾酮水平均下降了41% - 68%（P < 0.01 - 0.05）。在25、55和65日龄时，垂体中常见α亚基（下降28% - 55%）和促卵泡激素（FSH）β亚基（下降25% - 50%）的稳态mRNA水平降低（P < 0.01 - 0.05），但在35和45日龄时未出现这种情况；促黄体生成素（LH）β亚基在任何年龄段均无反应。禁食使25、55和65日龄大鼠的血清LH水平降低（P < 0.01），但在35和45日龄时未出现这种情况。同样，禁食仅使25日龄和65日龄大鼠的垂体和/或血清FSH水平降低（P < 0.01 - 0.05）。总之，短期禁食期间，仅青春期前（25日龄）和成年（65日龄）大鼠的LH和FSH分泌以及常见α亚基和FSHβ亚基的基因表达持续下降，而青春期前后的动物（35和45日龄）则未出现这种情况。因此，促性腺激素在青春期的升高代表了一种强烈的正向诱导作用，在很大程度上抵消了禁食的抗促性腺激素作用。
