Time-dependent changes of vasoactive substances in rat cerebral ischemia.
Time-dependent changes in the tissue concentration of tyrosine hydroxylase (TH), adrenaline (A), noradrenaline (NA), and neuropeptide Y (NPY) in the early stages of cerebral ischemia were studied immunohistochemically in the amygdaloid complex of rats subjected to 1 h cerebral ischemia. Immunoreactivity to TH on the lesioned side reached a nadir at 12 h after cerebral ischemia, then gradually increased over 24 h to normal reactivity, but TH immunoreactivity between the ischemic side and the contralateral side was no different for up to 12 h after ischemia. The blood concentrations of NA and A were elevated to about twice the control concentration 12 h after ischemia, then gradually decreased back to normal. NPY immunoreactivity of both sides did not change for up to 6 h after ischemia, but NPY immunoreactivity on the lesioned side decreased over 12 h and maintained a plateau. These findings suggest that responses to cerebral ischemia between catecholamines and peptides are varied.
Mizushima
H
H
Department of Neurosurgery, Showa University School of Medicine, Tokyo, Japan.
Sasaki
K
K
Shimazu
M
M
Arai
Y
Y
Matsumoto
K
K
Shioda
S
S
Nakai
Y
Y
D000818:Animals; D004837:Epinephrine / Q000097:blood; D007124:Immunoenzyme Techniques; D002546:Ischemic Attack, Transient / Q000378:metabolism*; D009478:Neuropeptide Y / Q000097:blood / Q000378:metabolism; D009638:Norepinephrine / Q000097:blood; D011863:Radioimmunoassay; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D014666:Vasomotor System / Q000378:metabolism*
D009478:Neuropeptide Y; D014446:Tyrosine 3-Monooxygenase; D009638:Norepinephrine; D004837:Epinephrine