Veldhuis J D, Johnson M L, Dufau M L
Department of Internal Medicine, University of Virginia School of Medicine, Charlottesville 22908.
Am J Physiol. 1989 Feb;256(2 Pt 1):E199-207. doi: 10.1152/ajpendo.1989.256.2.E199.
The exact nature of glandular secretory events is difficult to discern in vivo, since underlying patterns of hormone release are confounded by metabolic clearance. Moreover, conventional immunoassay does not always agree with bioassay. Here, we have used the rat interstitial cell testosterone in vitro bioassay of luteinizing hormone (LH) to measure serial LH concentrations in the normal adult human male. The resultant bioactive LH time series were analyzed by a deconvolution model in which circulating hormone concentrations are controlled by the operation of four finite, nonzero, and determinable parameters: 1) the location(s); 2) the amplitude(s), and 3) the half-duration(s) of underlying secretory bursts, acted on by 4) endogenous exponential clearance kinetics. A macroscopic secretory burst was modeled in the algebraic form of a Gaussian distribution of instantaneous molecular secretory rates. The physiological implications of this model were examined by analyzing bioactive LH pulsatility in eight men sampled every 10 min for 6 h. Multiple-parameter deconvolution disclosed endogenous bioactive LH half-lives of 53 +/- 5.4 min (range 38-76 min), in agreement with earlier independent estimates of 65 +/- 4.9 (42-87) min in four LH-deficient men given a 35 micrograms iv bolus of human LH. Calculated endogenous production rates of bioactive LH (0.48 +/- 0.06 mIU.min-1.ml-1) were also in accord with values estimated previously from steady-state infusions of LH. Deconvolution further indicated that underlying bioactive LH secretory bursts had half-durations of only 12.2 +/- 1.5 min, occurred at intervals of 56 +/- 1.3 min, and achieved amplitudes of 2.1 +/- 0.26 mIU.min-1.ml-1.(ABSTRACT TRUNCATED AT 250 WORDS)
在体内很难辨别腺分泌事件的确切性质，因为激素释放的潜在模式会被代谢清除所混淆。此外，传统免疫测定法与生物测定法的结果并不总是一致。在此，我们使用大鼠促黄体生成素（LH）的间质细胞睾酮体外生物测定法来测量正常成年男性体内LH的系列浓度。通过反卷积模型分析所得的生物活性LH时间序列，在该模型中，循环激素浓度由四个有限、非零且可确定的参数控制：1）潜在分泌脉冲的位置；2）幅度；3）半衰期，以及4）内源性指数清除动力学。以瞬时分子分泌速率的高斯分布代数形式对宏观分泌脉冲进行建模。通过分析每10分钟采样一次、共6小时的8名男性的生物活性LH搏动性，研究了该模型的生理学意义。多参数反卷积显示内源性生物活性LH半衰期为53±5.4分钟（范围38 - 76分钟），这与之前对4名LH缺乏男性静脉注射35微克人LH后独立估计的65±4.9（42 - 87）分钟一致。计算得出的内源性生物活性LH产生率（0.48±0.06 mIU·min⁻¹·ml⁻¹）也与之前通过LH稳态输注估计的值相符。反卷积进一步表明，潜在的生物活性LH分泌脉冲半衰期仅为12.2±1.5分钟，间隔为56±1.3分钟，幅度为2.1±0.26 mIU·min⁻¹·ml⁻¹。（摘要截短于250字）
