- 作者: Jenn-Tser Pan; Keith J. Lookingland; Kenneth E. Moore
- 作者服務機構: a Institute of Physiology, National; Yang-Ming Medical College, Taipei, Taiwan, Republic of China;; b Department of Pharmacology and; Toxicology, Michigan State University, East Lansing, Mich., USA
- 中文摘要: --
- 英文摘要: Corticotropin-releasing hormone (CRH) has been shown to be a central mediator for most, if not all, stress-induced responses. Since stressful stimuli may decrease hypothalamic tuberoinfundibular and tuberohypophysial dopa- minergic neuronal activities, we aimed to determine whether CRH is involved. Using central administration of various doses of ovine CRH (oCRH; 1, 3 and 10 μg/rat) into the lateral cerebroventricle of either male or female rats, the neurochemical changes in various parts of the central nervous system, including the hypothalamus, were determined by high-performance liquid chromatography at various times after the injection (30, 60, 120 and 240 min). The concentrations of 3,4-dihydroxyphenylacetic acid (DOPAC) and 3-methoxy-4-hydroxy-phenylethyleneglycol (MHPG), two major metabo- lites of dopamine and norepinephrine, respectively, in discrete brain regions were used as indices for catecholaminergic neuron activity. Plasma corticoste- rone levels increased significantly after all doses of oCRH and at all time points studied. oCRH also exerted significant stimulatory effects on noradren- ergic neuron terminals in the frontal cortex, and on dopaminergic neuron ter- minals in the nucleus accumbens, hypothalamic paraventricular and periven- tricular nuclei, and intermediate pituitary lobe. Dopaminergic neuron termi- nals in the median eminence and the neural lobe of the pituitary, however, were not affected. There was no major difference in the responses between male and female rats. We conclude that CRH has a differential effect on cen- tral catecholaminergic neurons.
- 中文關鍵字: --
- 英文關鍵字: Stress; Tuberoinfundibular dopamine; neuron; Frontal cortex; Nucleus accumbens; Pituitary, posterior and intermediate; Median eminence; Paraventricular nucleus; Corticotropin-releasing hormone