FOS-DETERMINED DISTRIBUTION OF NEURONS ACTIVATED DURING THE BEZOLD-JARISCH REFLEX IN THE MEDULLA-OBLONGATA IN CONSCIOUS RABBITS AND RATS

被引：19
作者：
GIEROBA, ZJ
MACKENZIE, L
WILLOUGHBY, JO
BLESSING, WW
机构：
[1] FLINDERS UNIV S AUSTRALIA, MED CTR, DEPT MED, BEDFORD PK, SA 5042, AUSTRALIA
[2] FLINDERS UNIV S AUSTRALIA, MED CTR, CTR NEUROSCI, BEDFORD PK, SA 5042, AUSTRALIA
[3] FLINDERS UNIV S AUSTRALIA, MED CTR, DEPT NEUROL, BEDFORD PK, SA 5042, AUSTRALIA
来源：
BRAIN RESEARCH | 1995年 / 683卷 / 01期
基金：
英国医学研究理事会;
关键词：
FOS; MEDULLA OBLONGATA; BEZOLD-JARISCH REFLEX;
D O I：
10.1016/0006-8993(95)00320-P
中图分类号：
Q189 [神经科学];
学科分类号：
071006 ;
摘要：
Experiments were performed in unanaesthetized rabbits and rats to investigate the distribution, within the medulla oblongata, of neurons activated during the Bezold-Jarisch reflex. Repeated intravenous injections of phenylbiguanide evoked depressor and bradycardic responses in both rabbits and rats. Fos-positive neurons were present in the nucleus tractus solitarius and in the caudal ventrolateral medulla oblongata. Double-label tyrosine hydroxylase (TH) immunohistochemical studies in the ventrolateral medulla showed that most Fos-positive neurons in the caudal ventrolateral medulla were TH-negative neurons scattered between A1 noradrenaline cells, in the rabbit and in the rat. Approximately 20% of neurons in the caudal ventrolateral medulla in rabbits, and 50% in rats, were immunoreactive for both Fos and TH. Some Fos-positive, TH-negative neurons in the caudal ventrolateral medulla were retrogradely labelled with cholera toxin B-Gold after injection of this tracer into the sympathoexcitatory region of the rostral ventrolateral medulla. Our data suggests that neurons in the nucleus tractus solitarius, and rostrally projecting TH-negative neurons in the caudal ventrolateral medulla, are part of the pathway by which stimulation of cardiopulmonary receptors inhibits sympathetic vasomotor tone to decrease blood pressure during the Bezold-Jarisch reflex.
引用
收藏
页码：43 / 50
页数：8
相关论文
共 39 条
  • [1] Agarwal, Calaresu, Monosynaptic connection from caudal to rostral ventrolateral medulla in the baroreceptor reflex pathway, Brain Res., 555, pp. 70-74, (1991)
  • [2] Badoer, McKinley, Oldfield, McAllen, Localization of barosensitive neurons in the caudal ventrolateral medulla which project to the rostral ventrolateral medulla, Brain Res., 657, pp. 258-268, (1994)
  • [3] Bell, O'Hagan, Clifford, Cardiac but not pulmonary receptors mediate depressor response to IV phenyl biguanide in conscious rabbits, Am. J. Physiol., 264, pp. R1050-R1057, (1993)
  • [4] Blessing, Distribution of glutamate decarboxylase-containing neurons in rabbit medulla oblongata with attention to intramedullary and spinal projections, Neuroscience, 37, pp. 171-185, (1990)
  • [5] Blessing, Depressor neurons in rabbit caudal medulla act via GABA receptors in rostral medulla, Am J Physiol, 254, pp. H686-H692, (1988)
  • [6] Blessing, Hedger, Joh, Willoughby, Neurons in the area postrema are the only catecholamine-synthesizing cells in the medulla or pons with projections to the rostral ventrolateral medulla (C1-area) in the rabbit, Brain Res., 419, pp. 336-340, (1987)
  • [7] Blessing, Li, Inhibitory vasomotor neurons in the caudal ventrolateral region of the medulla oblongata, Brain Res. Rev., 81, pp. 83-97, (1989)
  • [8] Bonham, Joad, Neurones in commissural nucleus tractus solitarii required for full expression of the pulmonary C fibre reflex in rat, J. Physiol., 441, pp. 95-112, (1991)
  • [9] Brodie, Russell, On reflex cardiac inhibition, J. Physiol., 26, pp. 92-106, (1990)
  • [10] Coleridge, Coleridge, Dangel, Kidd, Luck, Sleight, Impulses in slowly conducting vagal fibers from afferent endings in the veins, atria, and arteries of dogs and cats, Circ. Res., 33, pp. 87-97, (1973)
1234