RT Journal Article
SR Electronic
T1 Characterization, distribution, and ontogenesis of adenosine binding sites in cat visual cortex
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 3218
OP 3228
DO 10.1523/JNEUROSCI.06-11-03218.1986
VO 6
IS 11
A1 C Shaw
A1 SE Hall
A1 M Cynader
YR 1986
UL http://www.jneurosci.org/content/6/11/3218.abstract
AB In vitro autoradiographic techniques were used to characterize binding sites for 3H-cyclohexyladenosine (CHA) and 3H-5′-N- ethylcarboxamidoadenosine (NECA) in cat and kitten visual cortex. 3H- CHA binding sites in adult cat have a Bmax of 1,363 fmol/mg protein and a Kd of 6.8 nM. Displacement experiments indicate that 3H-CHA binds to an adenosine receptor similar to the A1-adenosine receptor described by other investigators. 3H-NECA binding sites in adult cat have a Bmax of 518 fmol/mg protein and a Kd of 15.4 nM. Displacement experiments do not allow us to identify this binding site unambiguously. Bmax values increase during postnatal development for both binding sites, peaking in adulthood for 3H-CHA and at 30 d for 3H-NECA. Kd values show neither consistent nor significant differences during postnatal development for either binding site. 3H-CHA and 3H-NECA binding sites are concentrated in layers 1–3 and upper layer 5 in the visual cortex of adult cats. These laminar patterns, however, change during postnatal development, showing the densest binding in the deep cortical layers (5 and 6) in kittens younger than 30 d of age and a fairly homogeneous binding in older kittens before achieving the adult distribution.