Characterization of a peripheral vanilloid (capsaicin) receptor in the urinary bladder of the rat.

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Citation

Szallasi A, Conte B, Goso C, Blumberg PM, Manzini S

Characterization of a peripheral vanilloid (capsaicin) receptor in the urinary bladder of the rat.

Life Sci. 1993;52(20):PL221-6.

PubMed ID
8483387 [ View in PubMed
]
Abstract

Specific binding of [3H]resiniferatoxin (RTX) is thought to represent the vanilloid (capsaicin) receptor. In the present study, we have used this binding assay to identify for the first time a vanilloid receptor in the periphery and to compare it to central vanilloid receptors present in dorsal root ganglia (DRG) as well as in spinal cord of the rat. Rat urinary bladder membranes bound [3H]RTX with a Kd of 30 +/- 4 pM and a Bmax of 65 +/- 14 fmol/mg protein; the corresponding values were 19 +/- 3 pM and 104 +/- 14 fmol/mg protein in DRG, and 16 +/- 3 pM and 50 +/- 9 fmol/mg protein in spinal cord. Capsaicin inhibited [3H]RTX binding to membranes from urinary bladder, spinal cord, and DRG with similar potency (Ki values were 0.5 +/- 0.1 microM, 0.3 +/- 0.1, and 0.6 +/- 0.1 microM, respectively). Interestingly, [3H]RTX bound to urinary bladder in a non-cooperative fashion in contrast with the apparent positive cooperativity of [3H]RTX binding in both DRG and spinal cord (cooperativity index = 1.8 and 1.7, respectively). This finding suggests heterogeneity in the properties of the vanilloid receptors in the rat.

DrugBank Data that Cites this Article

Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
ResiniferatoxinTransient receptor potential cation channel subfamily V member 1ProteinHumans
Unknown
Not AvailableDetails