Suttie J M, Fennessy P F, Corson I D, Laas F J, Crosbie S F, Butler J H, Gluckman P D
MAFTech, Invermay Agricultural Centre, Mosgiel, New Zealand.
J Endocrinol. 1989 May;121(2):351-60. doi: 10.1677/joe.0.1210351.
Plasma samples taken every 30 min over a 26-h period each month from six 4- to 15-month-old red deer stags were analysed for GH. In addition, two samples taken at 10.00 and 22.00 h were analysed for insulin-like growth factor-I (IGF-I) and insulin-like growth factor-II (IGF-II). A concentrate diet was available ad libitum. Food intake, body weight and antler status were recorded. Concentrations of GH were analysed using the PULSAR peak detection routine. Secretion of GH was pulsatile in every month of sampling, but the pattern of pulsatility differed seasonally. During the autumn and early winter (April-June in the Southern hemisphere) GH pulses were frequent and of low amplitude. In contrast, GH pulses in spring (August-September) were of high amplitude and high frequency resulting in a high mean level of GH circulating in the plasma. In early summer (November) the GH pulse amplitude was much lower and pulse frequency fell. There was a rise in GH pulse frequency not accompanied by an increase in GH pulse amplitude in summer (December-January). GH pulse amplitude seemed to be the main determinant of mean GH plasma level. Secretion of IGF-I was raised 1 month after peak monthly mean GH secretion. There was little consistent relationship between concentrations of IGF-II and mean daily GH. Concentrations of GH correlated positively and significantly with liveweight gain and antler growth rate with a delay of 1 month. Significantly positive correlations between concentrations of IGF-I, liveweight gain and antler growth rate were observed. It is considered that the spring and summer (September-December) seasonal acceleration of liveweight gain and antler development in stags could be a consequence of high winter/early spring (August-September) GH pulse frequency and amplitude resulting in increased concentrations of IGF-I, particularly in October.
每月从6头4至15个月大的马鹿雄鹿身上，每隔30分钟采集一次血浆样本，共采集26小时，对其进行生长激素（GH）分析。此外，对在10:00和22:00采集的两份样本进行胰岛素样生长因子-I（IGF-I）和胰岛素样生长因子-II（IGF-II）分析。提供不限量的精饲料。记录食物摄入量、体重和鹿茸状态。使用PULSAR峰值检测程序分析生长激素浓度。在每个采样月中，生长激素的分泌都是脉冲式的，但脉冲模式存在季节性差异。在秋季和初冬（南半球的4月至6月），生长激素脉冲频繁且幅度小。相比之下，春季（8月至9月）的生长激素脉冲幅度大、频率高，导致血浆中生长激素的平均水平较高。在初夏（11月），生长激素脉冲幅度低得多，脉冲频率下降。夏季（12月至1月）生长激素脉冲频率上升，但脉冲幅度没有增加。生长激素脉冲幅度似乎是血浆中生长激素平均水平的主要决定因素。胰岛素样生长因子-I的分泌在月平均生长激素分泌峰值后1个月升高。胰岛素样生长因子-II的浓度与每日平均生长激素之间几乎没有一致的关系。生长激素浓度与体重增加和鹿茸生长速度呈正相关且显著相关，存在1个月的延迟。观察到胰岛素样生长因子-I浓度、体重增加和鹿茸生长速度之间存在显著的正相关。据认为，雄鹿体重增加和鹿茸发育在春季和夏季（9月至12月）的季节性加速，可能是冬季/早春（8月至9月）生长激素脉冲频率和幅度较高，导致胰岛素样生长因子-I浓度增加的结果，尤其是在10月。
