Portal de Periódicos da CAPES

Glial Cell Line-Derived Neurotrophic Factor is a Survival Factor for Isolectin B4-Positive, but not Vanilloid Receptor 1-Positive, Neurons in the Mouse

2002; Society for Neuroscience; Volume: 22; Issue: 10 Linguagem: Inglês

10.1523/jneurosci.22-10-04057.2002

1529-2401

Melissa Zwick, Brian M. Davis, C. Jeffrey Woodbury, John N. Burkett, H. Richard Koerber, James F. Simpson, Kathryn M. Albers,

Ion Channels and Receptors

Most, if not all, nociceptor sensory neurons are dependent on nerve growth factor (NGF) during early embryonic development. A large subpopulation of these sensory neurons loses NGF dependency between embryonic day 16 and postnatal day 14 and become responsive to glial cell line-derived growth factor (GDNF), a member of the transforming growth factor beta (TGF-beta) family. To examine the survival and phenotypic effects of GDNF on sensory neurons in vivo, we generated transgenic mice that overexpress GDNF in the skin. GDNF-overexpresser mice had increased numbers of small unmyelinated sensory neurons that express the tyrosine kinase receptor Ret and bind the plant isolectin B4 (IB4). Surprisingly, in wild-type and transgenic mice, few ( approximately 2%) IB4-positive neurons expressed the vanilloid receptor VR1, a heat-sensitive receptor expressed by many IB4-positive neurons of the rat. Thus, in mouse, GDNF-dependent IB4-positive neurons must use a non-VR1 heat receptor. In addition, the behavior of GDNF-overexpresser animals to noxious heat or mechanical stimuli was indistinguishable from wild-type animals, indicating that, on a behavioral level, peripherally applied GDNF does not alter the sensitivity of the somatosensory system.