PMID- 1848632
OWN - NLM
STAT- MEDLINE
DCOM- 19910424
LR  - 20131121
IS  - 0022-3565 (Print)
IS  - 0022-3565 (Linking)
VI  - 256
IP  - 3
DP  - 1991 Mar
TI  - Pharmacologic characterization of GABAA/benzodiazepine receptor in rat 
      hippocampus during aging.
PG  - 902-8
AB  - We have characterized the pharmacologic properties of the gamma-aminobutyric acid 
      (GABAA)/benzodiazepine receptor complex in hippocampal membranes from 3-month- 
      and 24-month-old Wistar rats. No major changes were found in [3H]flunitrazepam or 
      [3H]muscimol binding parameters. Neither the dissociation constant(s) nor the 
      Bmax for either ligand seemed to be modified during aging in hippocampus. 
      Furthermore, the allosteric interaction between the barbiturates binding site and 
      the GABA binding site, determined by pentobarbital stimulation of [3H] muscimol 
      binding, remained unaltered. However, there was a significant increase with aging 
      in the efficacy of the GABA-enhancement of [3H]flunitrazepam binding. On the 
      other hand, we have also detected a significant increase in the proportion of 
      type I benzodiazepine receptor in 24-month-old hippocampal membranes. We propose 
      that the age-related increase in the efficacy of GABA-enhancement of 
      [3H]flunitrazepam binding could be correlated with the increase in the proportion 
      of type I benzodiazepine receptor. Based on these results it is tempting to 
      speculate that the age-dependent modifications on the GABAA/benzodiazepine 
      receptor might reflect an age-dependent neuronal degeneration of the hippocampus 
      or the hippocampal formation.
FAU - Ruano, D
AU  - Ruano D
AD  - Departamento de Bioquimica, Bromatologia y Toxicologia, Facultad de Farmacia, 
      Universidad de Sevilla, Spain.
FAU - Cano, J
AU  - Cano J
FAU - Machado, A
AU  - Machado A
FAU - Vitorica, J
AU  - Vitorica J
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Pharmacol Exp Ther
JT  - The Journal of pharmacology and experimental therapeutics
JID - 0376362
RN  - 0 (Receptors, GABA-A)
RN  - 2763-96-4 (Muscimol)
RN  - 56-12-2 (gamma-Aminobutyric Acid)
RN  - 620X0222FQ (Flunitrazepam)
RN  - I4744080IR (Pentobarbital)
SB  - IM
MH  - Aging/*metabolism
MH  - Animals
MH  - Binding Sites
MH  - Cerebellum/metabolism
MH  - Cerebral Cortex/metabolism
MH  - Culture Techniques
MH  - Drug Interactions
MH  - Flunitrazepam/metabolism
MH  - Hippocampus/*metabolism
MH  - Male
MH  - Muscimol/metabolism
MH  - Pentobarbital/pharmacology
MH  - Rats
MH  - Rats, Inbred Strains
MH  - Receptors, GABA-A/*metabolism
MH  - gamma-Aminobutyric Acid/pharmacology
EDAT- 1991/03/01 00:00
MHDA- 1991/03/01 00:01
CRDT- 1991/03/01 00:00
PHST- 1991/03/01 00:00 [pubmed]
PHST- 1991/03/01 00:01 [medline]
PHST- 1991/03/01 00:00 [entrez]
PST - ppublish
SO  - J Pharmacol Exp Ther. 1991 Mar;256(3):902-8.