Age-dependent increases of immunoreactive imidazoline receptors in the human brain: possible association of a 29/30 kDa protein with the I2-imidazoline receptor identified by [3H]idazoxan.
In the postmortem human brain (15 specimens of frontal cortex), the immunodetection and quantification of imidazoline receptor (IR) proteins (29/30 and 47 kDa) and the specific binding of [3H]idazoxan to I2-IR were determined in parallel to study the effect of aging (range 3-89 years) on these proteins and its possible association. The immunoreactivity of the 29/30 kDa IR protein, similar to the I2-IR, showed a significant positive correlation with the age of the subjects at death (r = 0.54; P = 0.04). Moreover, the levels of this IR protein also correlated significantly with the density of I2-IR in the brain of the same subjects (r = 0.67; P = 0.01). It is suggested that the I2-IR labeled by [3H]idazoxan in the human brain is related to the 29/30 kDa IR protein identified by immunoblot analysis.
García-Sevilla
J A
JA
Department of Fundamental Biology and Health Sciences, University of the Balearic Islands, Palma de Mallorca, Spain.
Sastre
M
M
Escribá
P V
PV
D000293:Adolescent; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism*; D015153:Blotting, Western; D001921:Brain / Q000187:drug effects / Q000254:growth & development*; D001923:Brain Chemistry / Q000187:drug effects / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D004146:Dioxanes / Q000494:pharmacology*; D005260:Female; D006801:Humans; D019329:Idazoxan; D007093:Imidazoles / Q000378:metabolism*; D054755:Imidazoline Receptors; D015151:Immunoblotting; D008297:Male; D008875:Middle Aged; D011955:Receptors, Drug / Q000187:drug effects / Q000378:metabolism*
D000317:Adrenergic alpha-Antagonists; D004146:Dioxanes; D007093:Imidazoles; D054755:Imidazoline Receptors; D011955:Receptors, Drug; D019329:Idazoxan