Brain‐Derived Neurotrophic Factor in the Brain of Xenopus laevis May Act as a Pituitary Neurohormone Together with Mesotocin

Journal of Neuroendocrinology - Tập 18 Số 6 - Trang 454-465 - 2006
Marinella Calle1, L. Wang1, F. J. Kuijpers1, Peter M. J. M. Cruijsen1, Lut Arckens2, Eric W. Roubos1
1Department of Cellular Animal Physiology, Institute for Neuroscience, Radboud University Nijmegen, Nijmegen, The Netherlands
2Laboratory of Neuroplasticity and Neuroproteomics, Katholieke Universiteit Leuven, Leuven, Belgium

Tóm tắt

AbstractBrain‐derived neurotrophic factor (BDNF), a member of the neurotrophin family, occurs abundantly in the brain, where it exerts a variety of neural functions. We previously demonstrated that BDNF also exists in the endocrine melanotroph cells in the intermediate lobe of the pituitary gland of the amphibian Xenopus laevis, suggesting that BDNF, in addition to its neural actions within the brain, can act as a hormone. In the present study, we tested whether BDNF, in addition to its neural and hormonal roles, can be released as a neurohormone from the neural pituitary lobe of X. laevis. By light immunocytochemistry, we show that BDNF is present in perikarya, in ventrolaterally projecting axons of the hypothalamic magnocellular nucleus and in the neural lobe of the pituitary gland, and that it coexists in these structures with the amphibian neurohormone, mesotocin. The neural lobe was studied in detail at the ultrastructural level. Two types of neurohaemal axon terminals were observed, occurring intermingled and in similar numbers. Type A is filled with round, moderately electron‐dense secretory granules with a mean diameter of approximately 145 nm. Type B terminals contain electron‐dense and smaller, ellipsoid granules (long and short diameter approximately 140 and 100 nm, respectively). BDNF is exclusively present in secretory granules of type A axon terminals. Double gold‐immunolabelling revealed that BDNF coexists in these granules with mesotocin. Furthermore, we demonstrate in an superfusion study performed in vitro that mesotocin stimulates peptide release from the endocrine melanotroph cells. On the basis of these data, we propose that BDNF can act on these cells as a neurohormone.

Từ khóa


Tài liệu tham khảo

10.1016/0166-2236(95)93922-K

10.1038/nrn1078

10.1146/annurev.neuro.22.1.295

10.1073/pnas.90.14.6711

10.1016/0006-8993(95)01321-0

10.1523/JNEUROSCI.10-11-03469.1990

10.1016/S0165-1781(02)00005-7

10.1016/S0006-3223(03)00181-1

10.1016/S0028-3908(98)00141-5

10.1016/j.ydbio.2003.12.001

10.1046/j.1365-2222.2003.01586.x

10.1016/0169-328X(94)90022-1

10.1097/00001756-199608120-00014

10.1002/(SICI)1097-4547(19970801)49:3<355::AID-JNR10>3.0.CO;2-Z

10.1111/j.1365-2826.2004.01110.x

10.1210/en.143.4.1337

10.1016/j.brainresprot.2005.07.001

10.1016/0196-9781(95)00049-P

10.1523/JNEUROSCI.12-03-00864.1992

10.1016/0306-4522(94)90241-0

10.1002/(SICI)1096-9861(19980720)397:1<60::AID-CNE5>3.0.CO;2-G

10.1177/002215549704501211

Jenks BG, 1993, Adaptation physiology: the functioning of pituitary melanotrope cells during background adaptation of the amphibian Xenopus laevis, Zool Sci, 10, 1

10.1016/S0300-9629(97)00035-2

Roubos EW, 2001, Perspectives in Comparative Endocrinology., 465

10.1016/S0016-6480(02)00013-8

10.1016/S1096-4959(01)00533-4

10.1007/BF00218707

10.1007/BF00221117

10.1007/BF00235162

10.1016/0891-0618(92)90003-9

10.1016/0361-9230(86)90203-0

10.1007/978-94-011-7674-3_1

Pang PK, 1978, Renal and vascular responses of the bullfrog (Rana catesbeiana) to mesotocin, Am J Physiol, 235, 151

10.2108/zsj.12.1

10.1016/0016-6480(86)90231-5

10.1016/0306-4522(89)90093-6

10.1016/0304-3940(89)90367-4

Vaudry H, 1977, Control of pituitary secretion of melanotropin in an anuran amphibian by thyrotropin releasing factor (TRH). Study in vitro, C R Acad Sci Hebd Séances Acad Sci D, 284, 961

10.1016/0196-9781(87)90167-7

10.1016/S0303-7207(98)00053-7

10.1210/en.140.7.3264

10.1016/0196-9781(87)90142-2

10.1016/j.brainres.2004.12.056

10.1002/cne.902640405

10.1016/0891-0618(95)00063-D

10.1111/j.1365-2826.2004.01247.x

10.1210/en.2004-0616