Esquifino A I, Arce A, Muñoz R M, Villanúa M A, Cardinali D P
Departamento de Bioquímica y Biología Molecular III, Facultad de Medicina, Universidad Complutense, Madrid, Spain.
J Neural Transm (Vienna). 1996;103(3):287-98. doi: 10.1007/BF01271240.
Eight days after bilateral superior cervical ganglionectomy (Gx) of rats, norepinephrine content of medial basal hypothalamus (MBH) decreased significantly by 44-50%. To obtain information on other possible neurochemical sequela of Gx in MBH, we examined the metabolism of dopamine and serotonin in MBH of Gx rats by employing a high pressure liquid chromatography procedure. Eight days after Gx, MBH dopamine levels augmented significantly. Assessment of dopamine metabolism by measuring dihydroxyphenylacetic acid (DOPAC)/dopamine and homovanillic acid (HVA)/dopamine indexes indicated a significant decrease of MBH DOPAC/dopamine ratio after Gx. MBH serotonin levels increased, and 5-hydroxyindoleacetic acid (5-HIAA)/serotonin index decreased significantly in Gx rats. To examine the interaction Gx-induced changes on MBH dopamine and serotonin with the modified hormonal milieu produced by an ectopic pituitary transplant, adult male rats bearing an ectopic pituitary within the pectoral muscles from day 5 of life were submitted to Gx on day 60 of life and were studied 8 days later. MBH dopamine content increased significantly after pituitary grafting, an effect counteracted by a subsequent Gx, while Gx alone augmented MBH dopamine levels. DOPAC and HVA contents augmented in pituitary-grafted animals, an effect counteracted by Gx. Gx increased MBH serotonin content in control but not in pituitary-grafted rats. After pituitary grafting a decrease in MBH 5-HIAA levels was found, an effect reversed by Gx. Pituitary transplants brought about a significant increase of MBH DOPAC/dopamine index, and a significant decrease in 5-HIAA/serotonin index, both effects being counteracted by Gx. Gx of control rats resulted in a significant decrease of MBH 5-HIAA/serotonin index. Analyzed as a main effect in a factorial analysis of variance, Gx decreased MBH DOPAC/dopamine and HVA/dopamine indexes significantly. Plasma prolactin increased in pituitary-grafted rats, an effect further increased by a subsequent Gx. In pituitary-grafted, Gx rats plasma GH levels augmented significantly. The data suggest that superior cervical ganglion removal affects differentially dopamine and indoleamine metabolism in MBH of control and pituitary-grafted rats.
大鼠双侧颈上神经节切除术后8天，内侧基底下丘脑（MBH）的去甲肾上腺素含量显著下降了44% - 50%。为了获取关于颈上神经节切除在MBH中其他可能的神经化学后遗症的信息，我们采用高压液相色谱法检测了颈上神经节切除大鼠MBH中多巴胺和5-羟色胺的代谢情况。颈上神经节切除术后8天，MBH多巴胺水平显著升高。通过测量二羟基苯乙酸（DOPAC）/多巴胺和高香草酸（HVA）/多巴胺指数来评估多巴胺代谢，结果显示颈上神经节切除后MBH的DOPAC/多巴胺比值显著降低。颈上神经节切除大鼠的MBH 5-羟色胺水平升高，5-羟吲哚乙酸（5-HIAA）/5-羟色胺指数显著降低。为了研究颈上神经节切除引起的MBH多巴胺和5-羟色胺变化与异位垂体移植所产生的改变的激素环境之间的相互作用，从出生第5天起在胸肌内植入异位垂体的成年雄性大鼠在出生第60天接受颈上神经节切除术，并在8天后进行研究。垂体移植后MBH多巴胺含量显著增加，随后的颈上神经节切除术可抵消这一效应，而单独的颈上神经节切除术则会提高MBH多巴胺水平。垂体移植大鼠的DOPAC和HVA含量增加，颈上神经节切除术可抵消这一效应。颈上神经节切除术使对照大鼠的MBH 5-羟色胺含量增加，但对垂体移植大鼠则无此作用。垂体移植后发现MBH 5-HIAA水平下降，颈上神经节切除术可逆转这一效应。垂体移植导致MBH的DOPAC/多巴胺指数显著升高，5-HIAA/5-羟色胺指数显著降低，这两种效应均被颈上神经节切除术抵消。对照大鼠的颈上神经节切除术导致MBH的5-HIAA/5-羟色胺指数显著降低。在方差分析的析因分析中作为主要效应进行分析时，颈上神经节切除术显著降低了MBH的DOPAC/多巴胺和HVA/多巴胺指数。垂体移植大鼠的血浆催乳素升高，随后的颈上神经节切除术使这一效应进一步增强。在垂体移植的颈上神经节切除大鼠中，血浆生长激素水平显著升高。数据表明，颈上神经节切除对对照大鼠和垂体移植大鼠MBH中的多巴胺和吲哚胺代谢有不同影响。
