Evidence that Orexin‐Containing Neurones Provide Direct Input to Gonadotropin‐Releasing Hormone Neurones in the Ovine Hypothalamus

Journal of Neuroendocrinology - Tập 13 Số 12 - Trang 1033-1041 - 2001
Jahangir Iqbal1, S. Pompolo1, Takashi Sakurai2, Iain J. Clarke1
1Prince Henry’s Institute of Medical Research, Clayton, Victoria, Australia
2Department of Pharmacology, Institute of Basic Medical Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan

Tóm tắt

AbstractOrexins A and B (ORX) have been added recently to the growing list of neuropeptides implicated in feeding and drinking behaviour as well as neuroendocrine function. In the present study, we have used single and dual labelling immunohistochemistry and a rabbit polyclonal anti‐orexin‐A antibody, which recognizes both ORX A and B, to examine ORX pathways in the sheep hypothalamus. ORX immunoreactive cells were distributed in the dorsomedial hypothalamic nucleus, lateral hypothalamic area, zona incerta and perifornical area; a few cells were also observed in the anterior hypothalamic area. In contrast to distribution in the rat brain, most of the ORX immunoreactive cells are localized to the dorsomedial hypothalamic nucleus and perifornical area; scattered cells are found in lateral hypothalamic area. ORX immunoreactive fibres were widely distributed throughout the hypothalamus and preoptic area with dense innervation of the medial preoptic area and bed nucleus of stria terminalis. Dual labelling demonstrated widespread expression of the long form of the leptin receptor within all ORX cells that were examined. Thirty percent of the gonadotropin releasing hormone (GnRH) cells that were examined had ORX immunoreactive terminals in close contact with no regional or sex differences. FluoroGold injections into the preoptic area retrogradely labelled a subpopulation of ORX cells in the lateral hypothalamic/perifornical area, showing ORX cells of this region project to the preoptic and could potentially provide input to GnRH cells. These findings suggest an integral role for ORX in the regulation of GnRH cells in the sheep and thus provide evidence of a novel mechanism whereby leptin can influence reproductive neuroendocrine function.

Từ khóa


Tài liệu tham khảo

10.1016/0149-7634(95)00015-1

10.1038/35007534

10.1159/000127118

10.1210/en.141.4.1506

10.1677/joe.0.170R001

10.1016/S0092-8674(00)80949-6

10.1073/pnas.95.1.322

10.1016/S0167-0115(99)00076-2

10.1016/S0006-8993(99)01884-3

10.1073/pnas.96.2.748

10.1523/JNEUROSCI.18-19-07962.1998

10.1016/S0014-5793(98)01266-6

10.1046/j.1365-2826.2000.00582.x

10.1006/bbrc.1999.1573

10.1016/S0167-0115(98)00128-1

10.1006/bbrc.2000.2245

10.1016/S0166-2236(00)01594-0

10.1016/S0092-8674(00)81973-X

Estabrooke I, 2000, Fos expression in orexin neurons varies with behavioral state, J Neurosci, 21, 1656, 10.1523/JNEUROSCI.21-05-01656.2001

10.1016/S0006-8993(99)01336-0

10.1523/JNEUROSCI.18-23-09996.1998

10.1046/j.1365-2826.1999.00378.x

10.1210/en.141.11.3946

10.1016/S0006-8993(00)02912-7

10.1111/j.1365-2826.2001.00588.x

10.1016/S0006-8993(99)01824-7

10.1016/S0196-9781(99)00105-9

10.1016/S0006-8993(99)01136-1

10.1210/endo.139.11.6297

10.1210/endo.141.11.7762

10.1159/000054335

10.1677/joe.0.1470565

10.1111/j.1365-2826.1993.tb00377.x

10.1210/endo.140.11.7093

10.1002/1096-9861(20001127)427:4<593::AID-CNE7>3.0.CO;2-C

10.1177/37.8.2666511

Tillet Y, 1989, Anatomical relationships of monoaminergic and neuropeptide Y‐containing fibers with luteinizing hormone‐releasing hormone systems in the preoptic area of the sheep brain: immunohistochemical studies, J Chem Neuroanat, 2, 319

10.1523/JNEUROSCI.19-03-01072.1999

10.1002/(SICI)1096-9861(19981228)402:4<442::AID-CNE2>3.0.CO;2-R

10.1016/S0006-8993(01)02372-1

10.1002/cne.903300205

Thông tin
Thông tin xuất bản

Journal of Neuroendocrinology

Tập 13 Số 12

1033-1041

Thông tin tác giả