Se. Asmus et al., Developmental changes in the transmitter properties of sympathetic neuronsthat innervate the periosteum, J NEUROSC, 20(4), 2000, pp. 1495-1504
During the development of sweat gland innervation, interactions with the ta
rget tissue induce a change from noradrenergic to cholinergic and peptiderg
ic properties. To determine whether the change in neurotransmitter properti
es that occurs in the sweat gland innervation occurs more generally in symp
athetic neurons, we identified a new target of cholinergic sympathetic neur
ons in rat, the periosteum, which is the connective tissue covering of bone
, and characterized the development of periosteal innervation of the sternu
m. During development, sympathetic axons grow from thoracic sympathetic gan
glia along rib periosteum to reach the sternum. All sympathetic axons displ
ayed catecholaminergic properties when they reached the sternum, but these
properties subsequently disappeared. Many axons lacked detectable immunorea
ctivities for vesicular acetylcholine transporter and vasoactive intestinal
peptide when they reached the sternum and acquired them after arrival. To
determine whether periosteum could direct changes in the neurotransmitter p
roperties of sympathetic neurons that innervate it, we transplanted periost
eum to the hairy skin, a noradrenergic sympathetic target. We found that th
e sympathetic innervation of the transplant underwent a noradrenergic to ch
olinergic and peptidergic change. These results suggest that periosteum, in
addition to sweat glands, regulates the neurotransmitter properties of the
sympathetic neurons that innervate it.