Absence of paravascular nerve projection and cross-innervation in interscapular brown adipose tissues of mice.
To determine whether a paravascular nerve projection or cross-innervation exists in the interscapular brown adipose tissue (BAT), the distribution of noradrenergic or peptidergic nerve fibers in intact or denervated interscapular BAT pads of mice was examined histochemically. Noradrenaline (NA) fibers were visualized by the glyoxylic acid condensation method, and neuropeptide Y (NPY) and substance P (SP) fibers were detected immunohistochemically. Numerous NA-positive fibers and a few NPY- or SP-positive fibers were observed around intralobular arterioles in intact BAT pads. Some NA-positive fibers and very few NPY- or SP-positive fibers were seen around interlobular arteries. NA- and NPY-positive fibers were also found around brown adipose cells in the parenchyme of BAT, whereas SP-positive fibers were absent around the cells. However, all sections cut from denervated BAT pads of unilaterally or bilaterally denervated animals showed a total absence of NA-, NPY- or SP-positive nerve fibers. Therefore, neither a paravascular projection of NA, NPY, and SP fibers to the BAT nor a cross-innervation of these nerve fibers between the left and right BAT pads exists in the mouse BAT.
Watanabe
J
J
Department of Anatomy, Kansai Medical University, Osaka, Japan.
Mishiro
K
K
Amatsu
T
T
Kanamura
S
S
D002001:Adipose Tissue, Brown / Q000294:innervation*; D000818:Animals; D001808:Blood Vessels / Q000294:innervation; D003714:Denervation; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009412:Nerve Fibers / Q000378:metabolism; D009478:Neuropeptide Y / Q000378:metabolism; D013373:Substance P / Q000378:metabolism; D009435:Synaptic Transmission
D009478:Neuropeptide Y; D013373:Substance P