Chronic stress increases the binding of the A1 adenosine receptor agonist, [3H]cyclohexyladenosine, to rat hypothalamus.
We previously reported an increase in the binding of [3H]cyclohexyladenosine ([3H]CHA) to brain membranes from the hypothalamus of rats sacrificed following three days of chronic stress in an around-the-clock intermittent footshock avoidance/escape paradigm ("sustained performance" stress). Here we report stress-induced increases in [3H]CHA binding to hypothalamic membranes from rats stressed for 14 days in that escape/avoidance paradigm, in rats exposed to repeated restraint (3 hr/day for 10 days) and in rats exposed to four days of "activity-stress." Data from saturation binding experiments indicate that this up-regulation was due to an increase in the apparent number of [3H]CHA binding sites without change in affinity for [3H]CHA. Neither restraint for one three-hr period nor one 15-min exposure to intermittent footshock resulted in significant changes in [3H]CHA binding to hypothalamic membranes. Our present data demonstrate small but consistent increases in the number of [3H]CHA binding sites in hypothalamic membranes from rats stressed in several different chronic stress models but no change by acute stress.
Anderson
S M
SM
Department of Medical Neurosciences, Walter Reed Army Institute of Research, Washington, DC 20307-5100.
Leu
J R
JR
Kant
G J
GJ
D000241:Adenosine / Q000031:analogs & derivatives* / Q000378:metabolism; D000818:Animals; D001667:Binding, Competitive; D005247:Feeding Behavior / Q000502:physiology; D007031:Hypothalamus / Q000378:metabolism*; D008297:Male; D005082:Physical Exertion; D011869:Radioligand Assay; D051381:Rats; D011919:Rats, Inbred Strains; D011983:Receptors, Purinergic / Q000378:metabolism*; D012149:Restraint, Physical; D013312:Stress, Physiological / Q000378:metabolism*
D011983:Receptors, Purinergic; C027513:N(6)-cyclohexyladenosine; D000241:Adenosine