The effect of heat shock on M-cholinoreceptors from rat cerebral cortex membranes.
The major parameters of binding the specific blocker [3H]quinuclidinyl benzylate were obtained for M-cholinoreceptors of rat cerebral cortex membranes. One receptor was shown to bind two molecules of the ligand; two discrete receptor pools were revealed, which differed in the sensitivity (Kd1 = 0.35 +/- 0.03; Kd2 = 1.79 +/- 0.21 nM) and the number of the ligand binding sites (B1 = 468 +/- 54; B2 = 864 +/- 81 fmol/mg protein). Heat shock decreased the number of receptors of the high-affinity pool (B1) by 16% (Kd1 did not differ from the control); the efficiency of the ligand binding to the receptors (E = B/2Kd) decreased by 26%, which suggests the decrease in the functional activity of the receptors of this pool. In the low-affinity pool (B2), the number of receptors increased by 39%, and Kd2 decreased by 22%; the efficiency (E2) increased by 14%.
Nesterova
L A
LA
Koltsov Institute of Developmental Biology, Russian Academy of Science, Moscow.
Smurova
E A
EA
Manukhin
B N
BN
D000311:Adrenal Glands / Q000737:chemistry; D000818:Animals; D001665:Binding Sites; D002462:Cell Membrane / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism* / Q000648:ultrastructure; D004837:Epinephrine / Q000378:metabolism; D005334:Fever / Q000503:physiopathology*; D006358:Hot Temperature / Q000009:adverse effects*; D007700:Kinetics; D008024:Ligands; D008297:Male; D009638:Norepinephrine / Q000378:metabolism; D011485:Protein Binding; D011813:Quinuclidinyl Benzilate / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011950:Receptors, Cholinergic / Q000378:metabolism*; D013997:Time Factors; D014316:Tritium
D008024:Ligands; D011950:Receptors, Cholinergic; D014316:Tritium; D011813:Quinuclidinyl Benzilate; D009638:Norepinephrine; D004837:Epinephrine