Peripheral-type benzodiazepine receptors are highly concentrated in mitochondrial membranes of rat testicular interstitial cells

The binding of 3H-RO 5-4864 to the peripheral-type benzodiazepine receptors (PBZDR) in rat testicular interstitial cells (TIC) was characterized. The binding was saturable, reversible and showed a single high-affinity (K(d) = 5.02 ± 0.86 nM) class of binding sites. The maximal binding capacity (B(ma...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Calvo, D.J., Ritta, M.N., Calandra, R.S., Medina, J.H.
Formato: JOUR
Materias:
rat
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_00283835_v52_n4_p350_Calvo
Aporte de:
id todo:paper_00283835_v52_n4_p350_Calvo
record_format dspace
spelling todo:paper_00283835_v52_n4_p350_Calvo2023-10-03T14:38:53Z Peripheral-type benzodiazepine receptors are highly concentrated in mitochondrial membranes of rat testicular interstitial cells Calvo, D.J. Ritta, M.N. Calandra, R.S. Medina, J.H. Benzodiazepine Mitochondrial membranes Peripheral receptor Testicular interstitial cells 4' chlorodiazepam diazepam flunitrazepam n sec butyl 1 (2 chlorophenyl) n methyl 3 isoquinolinecarboxamide radioisotope receptor animal cell article interstitium male mitochondrion nonhuman priority journal rat testis topical drug administration The binding of 3H-RO 5-4864 to the peripheral-type benzodiazepine receptors (PBZDR) in rat testicular interstitial cells (TIC) was characterized. The binding was saturable, reversible and showed a single high-affinity (K(d) = 5.02 ± 0.86 nM) class of binding sites. The maximal binding capacity (B(max)) in crude mitochondrial fractions (77.6 ± 9.1 pmol/mg protein) represents the highest density of PBZDR in tissues thus far studied. In comparison with the crude mitochondrial fraction the subcellular fractionation of of TIC revealed a 2-fold enrichment of 3H-RO 5-4864 binding sites to the purified mitochondria (B(max) = 140 ± 23 pmol/mg protein). The ability of various drugs to displace 3H-RO 5-4864 from TIC binding sites was examined and the inhibition constants (K(i)) for RO 5-4864, PK 11195, diazepam and flunitrazepam were 3.5, 4.4, 159, and 353 nM, respectively, whereas clonazepam and RO 15-1788 were inefficient in displacing 3H-RO 5-4864 (K(i) > 10 μM). This pharmacological profile is characteristic of PBZDR described in other tissues. In conclusion, rat TIC possess a very high concentration of PBZDR primarily associated with mitochondrial membranes. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00283835_v52_n4_p350_Calvo
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Benzodiazepine
Mitochondrial membranes
Peripheral receptor
Testicular interstitial cells
4' chlorodiazepam
diazepam
flunitrazepam
n sec butyl 1 (2 chlorophenyl) n methyl 3 isoquinolinecarboxamide
radioisotope
receptor
animal cell
article
interstitium
male
mitochondrion
nonhuman
priority journal
rat
testis
topical drug administration
spellingShingle Benzodiazepine
Mitochondrial membranes
Peripheral receptor
Testicular interstitial cells
4' chlorodiazepam
diazepam
flunitrazepam
n sec butyl 1 (2 chlorophenyl) n methyl 3 isoquinolinecarboxamide
radioisotope
receptor
animal cell
article
interstitium
male
mitochondrion
nonhuman
priority journal
rat
testis
topical drug administration
Calvo, D.J.
Ritta, M.N.
Calandra, R.S.
Medina, J.H.
Peripheral-type benzodiazepine receptors are highly concentrated in mitochondrial membranes of rat testicular interstitial cells
topic_facet Benzodiazepine
Mitochondrial membranes
Peripheral receptor
Testicular interstitial cells
4' chlorodiazepam
diazepam
flunitrazepam
n sec butyl 1 (2 chlorophenyl) n methyl 3 isoquinolinecarboxamide
radioisotope
receptor
animal cell
article
interstitium
male
mitochondrion
nonhuman
priority journal
rat
testis
topical drug administration
description The binding of 3H-RO 5-4864 to the peripheral-type benzodiazepine receptors (PBZDR) in rat testicular interstitial cells (TIC) was characterized. The binding was saturable, reversible and showed a single high-affinity (K(d) = 5.02 ± 0.86 nM) class of binding sites. The maximal binding capacity (B(max)) in crude mitochondrial fractions (77.6 ± 9.1 pmol/mg protein) represents the highest density of PBZDR in tissues thus far studied. In comparison with the crude mitochondrial fraction the subcellular fractionation of of TIC revealed a 2-fold enrichment of 3H-RO 5-4864 binding sites to the purified mitochondria (B(max) = 140 ± 23 pmol/mg protein). The ability of various drugs to displace 3H-RO 5-4864 from TIC binding sites was examined and the inhibition constants (K(i)) for RO 5-4864, PK 11195, diazepam and flunitrazepam were 3.5, 4.4, 159, and 353 nM, respectively, whereas clonazepam and RO 15-1788 were inefficient in displacing 3H-RO 5-4864 (K(i) > 10 μM). This pharmacological profile is characteristic of PBZDR described in other tissues. In conclusion, rat TIC possess a very high concentration of PBZDR primarily associated with mitochondrial membranes.
format JOUR
author Calvo, D.J.
Ritta, M.N.
Calandra, R.S.
Medina, J.H.
author_facet Calvo, D.J.
Ritta, M.N.
Calandra, R.S.
Medina, J.H.
author_sort Calvo, D.J.
title Peripheral-type benzodiazepine receptors are highly concentrated in mitochondrial membranes of rat testicular interstitial cells
title_short Peripheral-type benzodiazepine receptors are highly concentrated in mitochondrial membranes of rat testicular interstitial cells
title_full Peripheral-type benzodiazepine receptors are highly concentrated in mitochondrial membranes of rat testicular interstitial cells
title_fullStr Peripheral-type benzodiazepine receptors are highly concentrated in mitochondrial membranes of rat testicular interstitial cells
title_full_unstemmed Peripheral-type benzodiazepine receptors are highly concentrated in mitochondrial membranes of rat testicular interstitial cells
title_sort peripheral-type benzodiazepine receptors are highly concentrated in mitochondrial membranes of rat testicular interstitial cells
url http://hdl.handle.net/20.500.12110/paper_00283835_v52_n4_p350_Calvo
work_keys_str_mv AT calvodj peripheraltypebenzodiazepinereceptorsarehighlyconcentratedinmitochondrialmembranesofrattesticularinterstitialcells
AT rittamn peripheraltypebenzodiazepinereceptorsarehighlyconcentratedinmitochondrialmembranesofrattesticularinterstitialcells
AT calandrars peripheraltypebenzodiazepinereceptorsarehighlyconcentratedinmitochondrialmembranesofrattesticularinterstitialcells
AT medinajh peripheraltypebenzodiazepinereceptorsarehighlyconcentratedinmitochondrialmembranesofrattesticularinterstitialcells
_version_ 1807316545609662464