Age-related change of neuropeptide Y-immunoreactive neurons in the rat anterior olfactory nucleus.
Neuropeptide Y (NPY) is located in the olfactory system, including the olfactory bulb, and is thought to be one of the main neurotransmitters for olfaction. Thus, we examined age-related changes of NPY-immunoreactive (IR) neurons in the rat anterior olfactory nucleus (AON) at various aging stages over a period of 2 years; postnatal months 1 (PM 1), PM 6, PM 12 and PM 24. NPY-IR neurons in the AON were present in the lateral and medial subdivisions at PM 1 and at PM 6 were distributed in all subdivisions of the AON. Prior to PM 12, the NPY-IR neurons showed a tendency to change from bipolar cells with short processes into multipolar cells with long processes. Moreover, the population of NPY-IR neurons and nerve fibers in the AON increased in proportion to age. In particular, the number of NPY-IR neurons increased about 6-fold between PM 1 and PM 3. At PM 24, the number of NPY-IR neurons was much smaller than that at PM 12 and somal size had decreased. It is therefore suggested that the dramatic increase in the number and size of the NPY-IR neurons between PM 1 and PM 3 may be associated with sexual maturation and that the decrease in the number and cell size of the NPY-IR neurons at PM 24 may underlie age-related changes in the olfactory process.
Hwang
I K
IK
Department of Anatomy, College of Medicine, Hallym University, Chunchon 200-702, South Korea.
Kang
T C
TC
Park
S K
SK
An
S J
SJ
Suh
J G
JG
Lee
J Y
JY
Lee
I S
IS
Yoon
Y S
YS
Oh
Y S
YS
Won
M H
MH
D000375:Aging / Q000378:metabolism*; D000818:Animals; D001369:Axons / Q000378:metabolism / Q000648:ultrastructure; D002454:Cell Differentiation / Q000502:physiology; D048429:Cell Size / Q000502:physiology; D003712:Dendrites / Q000378:metabolism / Q000648:ultrastructure; D007150:Immunohistochemistry; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009478:Neuropeptide Y / Q000378:metabolism*; D009830:Olfactory Bulb / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D009833:Olfactory Pathways / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012903:Smell / Q000502:physiology*; D013569:Synapses / Q000378:metabolism / Q000648:ultrastructure; D009435:Synaptic Transmission / Q000502:physiology*
D009478:Neuropeptide Y