Van Wijk P A, Rijnberk A, Croughs R J, Voorhout G, Sprang E P, Mol J A
Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, University of Utrecht, The Netherlands.
Endocrinology. 1992 Dec;131(6):2659-62. doi: 10.1210/endo.131.6.1332844.
There is still some controversy concerning the question of whether Cushing's disease in man is caused by a primary dysfunction of the pituitary or a hypothalamic disorder. In the latter option, excessive hypothalamic stimulation of pituitary corticotropes would cause or contribute to the genesis of POMC-secreting adenomas. In the present study cerebrospinal fluid (CSF) CRH levels and levels of ACTH and cortisol in CSF and plasma were measured in clinically healthy dogs, in dogs with pituitary-dependent hyperadrenocorticism (PDH), and in dogs with hyperadrenocorticism due to an adrenocortical tumor (ATH). In CSF from dogs with PDH, CRH concentrations (226.6 +/- 14.4 ng/liter) were significantly (P < 0.05) lower than those in control dogs (309.5 +/- 20.3 ng/liter). In the dogs with ATH, CSF CRH concentrations (211.0 +/- 40.3 ng/liter) were in the range of those in PDH dogs. In dogs with ATH, CSF ACTH levels (13.0 +/- 3.0 ng/liter) were significantly (P < 0.05) lower than those in control dogs (63.4 +/- 3.5 ng/liter), whereas in dogs with PDH, the levels (116.8 +/- 47.5 ng/liter) were not different from those in the control group. In control dogs, the concentrations of CSF CRH and plasma ACTH were significantly correlated (r = 0.635; P < 0.01). This functional dependency appeared to be disturbed in dogs with PDH, as in these dogs CSF CRH concentrations did not correlate with plasma ACTH concentrations. It is concluded that continuous hyperstimulation of pituitary corticotropes with hypothalamic CRH is probably not the cause of excessive ACTH secretion in dogs with pituitary-dependent hyperadrenocorticism.
关于人类库欣病是由垂体原发性功能障碍还是下丘脑疾病引起的问题，仍然存在一些争议。在后一种情况下，下丘脑对垂体促肾上腺皮质激素细胞的过度刺激会导致或促成分泌促肾上腺皮质激素原（POMC）的腺瘤的发生。在本研究中，测量了临床健康犬、垂体依赖性肾上腺皮质功能亢进（PDH）犬和肾上腺皮质肿瘤（ATH）所致肾上腺皮质功能亢进犬的脑脊液（CSF）促肾上腺皮质激素释放激素（CRH）水平以及CSF和血浆中促肾上腺皮质激素（ACTH）和皮质醇的水平。在PDH犬的CSF中，CRH浓度（226.6±14.4纳克/升）显著低于对照犬（309.5±20.3纳克/升）（P<0.05）。在ATH犬中，CSF CRH浓度（211.0±40.3纳克/升）与PDH犬的浓度范围相同。在ATH犬中，CSF ACTH水平（13.0±3.0纳克/升）显著低于对照犬（63.4±3.5纳克/升）（P<0.05），而在PDH犬中，该水平（116.8±47.5纳克/升）与对照组无差异。在对照犬中，CSF CRH浓度与血浆ACTH浓度显著相关（r = 0.635；P<0.01）。在PDH犬中，这种功能依赖性似乎受到了干扰，因为在这些犬中CSF CRH浓度与血浆ACTH浓度不相关。得出的结论是，下丘脑CRH对垂体促肾上腺皮质激素细胞的持续过度刺激可能不是垂体依赖性肾上腺皮质功能亢进犬ACTH分泌过多的原因。
