Densities of neuropeptide receptors in brain tissues of different species

Receptor

Density

in fmol/mg

Species

Region

Method

Ligand

References

µ opioid

120 and 240

Rat

Brain homogenate

Membrane binding

ß_h-[³H]endorphin

[79]

9.2 - 137

Mice

Striatum, thalamus, red nuclei

Autoradiography

[³H]DAMGO

[84]

8.1 - 38.1

Human

Cortex

Autoradiography

[³H]DAGO

[83]

δ opioid

14 - 86

Mice

Frontal+

cingulate cortex

Autoradiography

[³H]DELTI

[84]

27.3 - 56.2

Human

Cortex

Autoradiography

[³H]DSLET

[83]

κ1 opioid

2.9 - 84.6

Mice

Striatum, accumbens, hypothalamus

Autoradiography

[³H]Cl-977

[84]

κ opioid

6.6 - 120

Mice

Striatum, temporal cortex, accumbens, hypothalamus

Autoradiography

[³H]bremazocine

[84]

15.0 - 111.8

Human

Cortex

Autoradiography

[³H]bremazocine^*

[83]

Opioid (total: 41% - 59% κ; 33% - 49% µ; 8% - 15% δ)

10 - 33

Human

Spinal cord (dorsal horn: Lamina I-III; lissauer tract)

Autoradiography

Diprenorphine

[82]

Neurotensin NTS1/NTS2

527

Sprague Dawley rats

Brain without cerebellum

Membrane binding

SR142948A in absence of 10 µM levocabastine

[112]

NTS1

104

Sprague Dawley rat

“

Membrane binding

SR142948 in Presence of levocabastine

[112]

NTS2

422

Sprague Dawley rat

“

“

SR142948 in Presence of levocabastine

[112]

CGRP

214 - 250

Rat

Hypothalamus

Membrane binding

[¹²⁵I]CGRP

[113]

[114]

Bradykinin

B2

0.9 - 1.9

Rat

NTS/area postrema, spinal trigeminal nucleus, vagal dorsal motor nucleus

Spinal cord

Autoradiography

[¹²⁵I-Tyr⁰-Bradykinin

[115]

1.8 - 4.5

Rat

Spinal cord

Autoradiography

[¹²⁵I-Tyr⁸-Bradykinin

[116]

NK1

94

Gerbil

Cortex

Autoradiography

[³H]GR205171

[44]

607

Gerbil

Striatum

59 - 74

Human

Cortex

318 - 432

Human

Striatum

8.67 - 13.24^***

Rat

Spinal cord

Autoradiography

[¹²⁵I]BH-SP

[203]

NK2

7.3

Rat

Hippocampus

Membrane binding,

Autoradiography

[¹²⁵I]NKA

[117]

1.65 - 2.55^***

Rat

Spinal cord

Autoradiography

“

[203]

NK3

31.2

Rat

Cortex

Autoradiography

[³H]Senktide

[118]

2.53 - 3.08^***

Rat

Spinal cord

Autoradiography

[¹²⁵I]BP-ED

[203]