Nerve growth factor is present in skin in limiting amounts and is known to
regulate the plasticity and the sensitivity of nociceptive neurons. Recentl
y, knock-out mouse studies showed that neurotropkin-3 and brain-derived neu
rotrophic factor are required for the postnatal survival and functional mat
uration, respectively, of tactile sensory neurons. However, the roles of ne
urotrophin-3 and brain-derived neurotrophic factor in adult sensory neurons
have not been clarified. Here, we report an unexpected and marked acute lo
ss of tactile sense in the rat hind paw after adjuvant-induced inflammation
. This loss was shown to be closely correlated with decreases in the expres
sion of brain-derived neurotrophic factor, and to a lesser extent of neurot
rophin-3 in the inflamed skin. Administration of brain-derived neurotrophic
factor, but not neurotrophin-3, after inflammation accelerated the recover
y of tactile sense.
These results suggested a role of brain-derived neurotrophic factor in the
physiological regulation of tactile sense in adulthood. (C) 2000 IBRO. Publ
ished by Elsevier Science Ltd.