Reversible down-regulation of liver cyclo(His-Pro) binding sites by cyclo(His-Pro) administration to mice.
Intraperitoneal injections of histidyl-proline diketopiperazine [cyclo(His-Pro), 15 mg/kg/day] to mice for 3 days caused a significant loss of cyclo(His-Pro) binding sites in the liver. This loss depended on the decrease in the number of binding sites and not on the change in affinity. The cyclo(His-Pro)-mediated loss was reversible, and the specific binding returned to the original level within 3 days of the cessation of cyclo(His-Pro). These results suggest that cyclo(His-Pro) participates in regulating its own binding sites in the liver.
D000818:Animals; D066298:In Vitro Techniques; D008099:Liver / Q000032:analysis*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D010456:Peptides, Cyclic / Q000494:pharmacology*; D010879:Piperazines / Q000494:pharmacology*; D017981:Receptors, Neurotransmitter / Q000032:analysis* / Q000187:drug effects; D018025:Receptors, Thyrotropin-Releasing Hormone
D010456:Peptides, Cyclic; D010879:Piperazines; D017981:Receptors, Neurotransmitter; D018025:Receptors, Thyrotropin-Releasing Hormone; C015924:histidyl-proline diketopiperazine