Porter I D, Whitehouse B J, Price G M, Hinson J P, Vinson G P
Biomedical Sciences Division, King's College London, U.K.
J Endocrinol. 1992 May;133(2):275-82. doi: 10.1677/joe.0.1330275.
The rat adrenal cortex contains quantities of dopamine that are compatible with its function as a neurotransmitter, suggesting that locally released dopamine may act as a neuroregulator within the gland. This possibility has been tested by comparing the effects of dopamine on aldosterone secretion in the perfused adrenal with the effects of stimuli designed to provoke the release of intraglandular dopamine. Infusion of dopamine (0.1-100 mumol/l for 10-min periods) into the isolated perfused rat adrenal gland resulted in a transient, dose-related reduction of aldosterone secretion to a minimum of approximately 50% of the basal value at 1 mumol dopamine/l (ratio of experimental to control measurements, R = 0.53 +/- 0.06 (S.E.M.); n = 5). In contrast, dopamine (1-100 mumol/l) had no effect on aldosterone production by dispersed zona glomerulosa cell preparations incubated in vitro. The effects of changes in K+ concentration (3.9-52 mmol/l) on aldosterone secretion in the perfused gland and dispersed cell preparations were also compared. A similar bell-shaped dose-response relationship was seen in both preparations between 6 and 32 mmol K+/l, with a maximum at 8.4 mmol K+/l and a return to control values with 16, 24 or 32 mmol K+/l. However, infusion of media with very high K+ concentrations (42 or 52 mmol K+/l) reduced the secretion of aldosterone by the perfused gland to approximately 50% of the basal value (R = 0.51 +/- 0.05, n = 9; R = 0.49 +/- 0.08, n = 9; respectively) but produced no change in aldosterone production by zona glomerulosa cells.(ABSTRACT TRUNCATED AT 250 WORDS)
大鼠肾上腺皮质含有一定量的多巴胺，其含量与其作为神经递质的功能相符，这表明局部释放的多巴胺可能在腺体内充当神经调节因子。通过比较多巴胺对灌注肾上腺中醛固酮分泌的影响与旨在激发腺体内多巴胺释放的刺激的影响，对这一可能性进行了测试。向离体灌注的大鼠肾上腺中输注多巴胺（0.1 - 100 μmol/l，持续10分钟）导致醛固酮分泌出现短暂的、剂量相关的减少，在1 μmol多巴胺/l时降至基础值的约50%（实验与对照测量值之比，R = 0.53 ± 0.06（标准误）；n = 5）。相比之下，多巴胺（1 - 100 μmol/l）对体外培养的分散的球状带细胞制备物中醛固酮的产生没有影响。还比较了K⁺浓度变化（3.9 - 52 mmol/l）对灌注腺体和分散细胞制备物中醛固酮分泌的影响。在6至32 mmol K⁺/l之间，两种制备物中均观察到类似的钟形剂量反应关系，在8.4 mmol K⁺/l时达到最大值，在16、24或32 mmol K⁺/l时恢复到对照值。然而，输注含非常高K⁺浓度（42或52 mmol K⁺/l）的培养基会使灌注腺体中醛固酮的分泌降至基础值的约50%（分别为R = 0.51 ± 0.05，n = 9；R = 0.49 ± 0.08，n = 9），但对球状带细胞中醛固酮的产生没有影响。（摘要截断于250字）
