Logan J L, Benson B, Lee S M
Growth. 1985 Spring;49(1):78-90.
The transfer of Syrian golden hamsters from a long to a short photoperiod (SP) leads to reduced circulating levels of several anterior pituitary hormones including thyrotropin stimulating hormone (TSH), luetinizing hormone (LH) and follicle stimulating hormone (FSH), while growth hormone (GH) is unaffected. These hormonal changes are associated with accelerated rates of body weight gain and gonadal atrophy in this species, but the effects on growth of other organs, specifically the kidney, are unknown. In this study, the effect of SP treatment on kidney and body weights of intact and uninephrectomized male Syrian golden hamsters was evaluated. Seventy-two young adult male hamsters were acclimatized to long photoperiod (LP) consisting of a light/dark schedule of 14/10 hours (LD 14:10). Two weeks later one half of the animals were transferred to SP (LD 10:14) Subgroups of six hamsters underwent either left nephrectomy or sham left nephrectomy two, five and eight weeks after transfer to SP and were sacrificed two weeks after surgery. The relative kidney weights (kidney weights/100 g body weight) of the sham operated animals were significantly reduced after seven and ten weeks of SP treatment (p less than 0.01). Absolute kidney weights were depressed after eight (p less than 0.05) and ten weeks in SP. The percentage increase in the weight of the hypertrophied kidney following uninephrectomy was unaffected by SP. Differences in body weights were due to increased fat in SP-treated hamsters; nonetheless, the logs of kidney and body weights were highly correlated in both LP (r = 0.73) and SP (r = 0.78). Lean body weights, determined by body compositional analysis, were less well correlated with kidney weights in LP (r = 0.53) and unrelated in SP (r = 0.16). The mechanism retarding kidney growth was not elucidated, but may include SP-induced changes in TSH, LH, or a specific LH-like pituitary renotropin proposed by Nomura et al. (1982). The observation that compensatory renal growth proceeds despite inhibition of kidney growth in intact animals suggests that separate mechanisms regulate these processes.
将叙利亚金黄地鼠从长光照周期转移至短光照周期（SP）会导致几种垂体前叶激素的循环水平降低，包括促甲状腺激素（TSH）、促黄体生成素（LH）和促卵泡生成素（FSH），而生长激素（GH）不受影响。这些激素变化与该物种体重增加加速和性腺萎缩有关，但对其他器官，特别是肾脏生长的影响尚不清楚。在本研究中，评估了SP处理对完整和单侧肾切除的雄性叙利亚金黄地鼠肾脏和体重的影响。72只成年雄性地鼠适应了由14/10小时光照/黑暗时间表组成的长光照周期（LP，即LD 14:10）。两周后，将一半动物转移至SP（LD 10:14）。在转移至SP后2周、5周和8周，对每组6只地鼠进行左侧肾切除术或假左侧肾切除术，并在手术后2周处死。假手术动物的相对肾脏重量（肾脏重量/100克体重）在SP处理7周和10周后显著降低（p小于0.01）。在SP处理8周（p小于0.05）和10周后，绝对肾脏重量降低。单侧肾切除术后肥大肾脏重量增加的百分比不受SP影响。体重差异是由于SP处理的地鼠脂肪增加所致；尽管如此，在LP组（r = 0.73）和SP组（r = 0.78）中，肾脏重量与体重的对数高度相关。通过身体成分分析确定的瘦体重与LP组肾脏重量的相关性较差（r = 0.53），与SP组无关（r = 0.16）。延缓肾脏生长的机制尚未阐明，但可能包括SP诱导的TSH、LH变化，或Nomura等人（1982年）提出的一种特定的类似LH的垂体肾营养激素。完整动物中尽管肾脏生长受到抑制，但代偿性肾脏生长仍在进行，这一观察结果表明，存在不同的机制调节这些过程。
