> Trialight public data. Index of pages: https://trialight.com/llms.txt
> Web page: https://trialight.com/data/target/oprk1-7b0a0fa0-a4b4-537b-bd00-d871256424e5
> Record changed: 2026-10-13

# OPRK1

ENSG00000082556

Target class

GPCR

Chromosome

8

Approved drugs

24

Clinical candidates (approved and in development)

32

## Clinical evidence

**Approved drugs**

24

**Clinical candidates (approved and in development)**

32

## Druggability

**Chemical probe available**

Yes

## Names

**Target name**

OPRK1

**Gene name**

Opioid receptor kappa 1

**Gene symbol**

OPRK1

**Protein name**

Kappa-type opioid receptor (K-OR-1) (KOR-1)

### Other names (2)

- KOR
- OPRK

## Classification

**Gene biotype**

Protein coding

**Gene family**

Opioid receptors

**Target class**

GPCR

**Target type**

Human gene

## Expression and localisation

**Tissues expressed in**

9

**Protein localisation evidence grade**

Supported

**Highest tissue expression**

4.08

**Tissue specificity (Gini)**

0.805

**Tissue specificity (tau)**

0.928

## Pathways and interactions

**KEGG gene identifiers**

- hsa:4986

### Reactome pathways (3)

- R-HSA-375276
- R-HSA-418594
- R-HSA-9022699

## Genomic location

**End position**

53251637

**Start position**

53225724

**Chromosome**

8

**Strand**

Reverse

## Identifiers

**Ensembl gene ID**

ENSG00000082556

**HGNC ID**

HGNC:8154

Source: [www.genenames.org](https://www.genenames.org/data/gene-symbol-report/#!/hgnc%5Fid/HGNC:8154)

**NCBI Gene ID**

4986

**UniProt ID**

P41145

## Cellular location

- Cell membrane
- Multi-pass membrane protein .
- Plasma membrane

### Publication evidence (4)

- PubMed 12004055  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/12004055/)
- PubMed 22437504  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/22437504/)
- PubMed 7624359  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/7624359/)
- PubMed 8060324  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/8060324/)

## Tissue expression

**Tissue specificity (tau)**

0.927997

**Expression inequality (Gini)**

0.804816

### Highest expression

Expression in transcripts per million

**Brain - Nucleus accumbens (basal ganglia)**

4.08

**Brain - Hypothalamus**

2.37

**Brain - Anterior cingulate cortex (BA24)**

1.84

**Brain - Frontal Cortex (BA9)**

1.58

**Brain - Caudate (basal ganglia)**

1.55

### All tissues (54)

Expression in transcripts per million

- Brain - Nucleus accumbens (basal ganglia)4.08
- Brain - Hypothalamus2.37
- Brain - Anterior cingulate cortex (BA24)1.84
- Brain - Frontal Cortex (BA9)1.58
- Brain - Caudate (basal ganglia)1.55
- Brain - Amygdala1.28
- Brain - Cortex1.24
- Brain - Cerebellum1.04
- Brain - Cerebellar Hemisphere1.04
- Testis0.84
- Brain - Putamen (basal ganglia)0.62
- Prostate0.4
- Brain - Hippocampus0.4
- Brain - Substantia nigra0.28
- Adipose - Subcutaneous0.2
- Pituitary0.18
- Artery - Aorta0.12
- Heart - Atrial Appendage0.09
- Brain - Spinal cord (cervical c-1)0.09
- Colon - Sigmoid0.08
- Thyroid0.05
- Artery - Tibial0.03
- Colon - Transverse0.03
- Breast - Mammary Tissue0.02
- Minor Salivary Gland0.02

And 29 more, listed on the interactive page.

## Biological functions

### Biological processes (7)

- GO:0006955  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0006955)
- GO:0007193  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0007193)
- GO:0007268  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0007268)
- GO:0007600  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0007600)
- GO:0031635  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0031635)
- GO:0038003  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0038003)
- GO:0051607  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0051607)

### Cellular components (2)

- GO:0005886  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0005886)
- GO:0016020  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0016020)

### Molecular functions (3)

- GO:0004985  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0004985)
- GO:0005515  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0005515)
- GO:0038048  
Source: [www.ebi.ac.uk](https://www.ebi.ac.uk/QuickGO/term/GO:0038048)

## On-target safety

- tachycardia  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - clinical: tachycardia  
### Biological samples (2)

  - cardiovascular system
  - nervous system  
Evidence source  
Source: [doi.org](https://doi.org/10.1002/9781118098141.ch2)
- interaction with dopaminergic transmission and hallucination  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - clinical: interaction with dopaminergic transmission and hallucination  
### Biological samples (2)

  - cardiovascular system
  - nervous system  
Evidence source  
Source: [doi.org](https://doi.org/10.1002/9781118098141.ch2)
- dizziness  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: dizziness  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- decreased/increased heart rate  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: decreased/increased heart rate  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- increased convulsions  
### Effects

  - Inhibition/Decrease/Downregulation: acute  
### Studies

  - preclinical: increased convulsions  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- increased/decreased eating  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: increased/decreased eating  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- decreased body temperature  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: decreased body temperature  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- decreased eating  
### Effects

  - Inhibition/Decrease/Downregulation: acute  
### Studies

  - preclinical: decreased eating  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- psychotomimetic effects  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - clinical: psychotomimetic effects  
### Biological samples (2)

  - cardiovascular system
  - nervous system  
Evidence source  
Source: [doi.org](https://doi.org/10.1002/9781118098141.ch2)
- diuresis  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - clinical: diuresis  
### Biological samples (2)

  - cardiovascular system
  - nervous system  
Evidence source  
Source: [doi.org](https://doi.org/10.1002/9781118098141.ch2)
- decreased convulsions  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: decreased convulsions  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- decreased cardiac contractility  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: decreased cardiac contractility  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- hypotension  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - clinical: hypotension  
### Biological samples (2)

  - cardiovascular system
  - nervous system  
Evidence source  
Source: [doi.org](https://doi.org/10.1002/9781118098141.ch2)
- increased urine excretion  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: increased urine excretion  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- increased anxiety  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: increased anxiety  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- decreased inflammation  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: decreased inflammation  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- drug abuse/dependence  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: drug abuse/dependence  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- dysphoria  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - clinical: dysphoria  
### Biological samples (2)

  - cardiovascular system
  - nervous system  
Evidence source  
Source: [doi.org](https://doi.org/10.1002/9781118098141.ch2)
- confusion  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: confusion  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- paresthesia  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - clinical: paresthesia  
### Biological samples (2)

  - cardiovascular system
  - nervous system  
Evidence source  
Source: [doi.org](https://doi.org/10.1002/9781118098141.ch2)
- antipruritic effects  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - clinical: antipruritic effects  
### Biological samples (2)

  - cardiovascular system
  - nervous system  
Evidence source  
Source: [doi.org](https://doi.org/10.1002/9781118098141.ch2)
- dizziness  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - clinical: dizziness  
### Biological samples (2)

  - cardiovascular system
  - nervous system  
Evidence source  
Source: [doi.org](https://doi.org/10.1002/9781118098141.ch2)
- analgesia  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - clinical: analgesia  
### Biological samples (2)

  - cardiovascular system
  - nervous system  
Evidence source  
Source: [doi.org](https://doi.org/10.1002/9781118098141.ch2)
- decreased locomotor activity  
### Effects

  - Activation/Increase/Upregulation: acute  
### Studies

  - preclinical: decreased locomotor activity  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)
- decreased drinking  
### Effects

  - Inhibition/Decrease/Downregulation: acute  
### Studies

  - preclinical: decreased drinking  
### Biological samples (3)

  - nervous system
  - cardiovascular
  - gastrointestinal  
PubMed 28216264  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/28216264/)

And 9 more, listed on the interactive page.

## Off-target safety

- dizziness  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - preclinical: dizziness  
### Biological samples (3)

  - cardiovascular system
  - central nervous system
  - gastrointestinal  
PubMed 23197038  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/23197038/)
- decreased gastrointestinal motility  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - preclinical: decreased gastrointestinal motility  
### Biological samples (3)

  - cardiovascular system
  - central nervous system
  - gastrointestinal  
PubMed 23197038  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/23197038/)
- tachycardia  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - preclinical: tachycardia  
### Biological samples (3)

  - cardiovascular system
  - central nervous system
  - gastrointestinal  
PubMed 23197038  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/23197038/)
- sedation  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - preclinical: sedation  
### Biological samples (3)

  - cardiovascular system
  - central nervous system
  - gastrointestinal  
PubMed 23197038  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/23197038/)
- increased urinary output  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - preclinical: increased urinary output  
### Biological samples (3)

  - cardiovascular system
  - central nervous system
  - gastrointestinal  
PubMed 23197038  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/23197038/)
- decreased locomotion  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - preclinical: decreased locomotion  
### Biological samples (3)

  - cardiovascular system
  - central nervous system
  - gastrointestinal  
PubMed 23197038  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/23197038/)
- dysphoria  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - preclinical: dysphoria  
### Biological samples (3)

  - cardiovascular system
  - central nervous system
  - gastrointestinal  
PubMed 23197038  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/23197038/)
- confusion  
### Effects

  - Activation/Increase/Upregulation: general  
### Studies

  - preclinical: confusion  
### Biological samples (3)

  - cardiovascular system
  - central nervous system
  - gastrointestinal  
PubMed 23197038  
Source: [pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/23197038/)

## Related records

### Trials (1,494)

- \[11C\]Carfentanil PET Study of GSK1521498
- 4-drug Nerve Block Versus Plain Local Anesthetic for Knee and Hip Arthroplasty Analgesia in Veterans
- 5HT3 Antagonists to Treat Opioid Withdrawal and to Prevent the Progression of Physical Dependence
- 5x-Multiplier vs 3-Tier Model for Discharge Opioid Prescriptions After Intra-abdominal Cancer Surgery: A Randomized Clinical Trial
- A 5 Treatment Period Pharmacokinetic Study Evaluating Dose Proportionality and Food Effects of Diazoxide Choline Controlled-Release Tablet (DCCR)
- A Bioavailability and Safety Study of Probuphine Versus Sublingual Buprenorphine in Patients With Opioid Dependence
- A Bioavailability Study of NALDEBAIN ER Injection and Nalbuphine Injection in Healthy Volunteers.
- A Bundled Intervention to End Opioid Overdoses
- A Clinical Study in Healthy Adults Who Sometimes Take Drugs for Pleasure to Investigate the Safety and Tolerability of GRT0151Y and to Find Out Which Single Dose of the Compound is Maximally Tolerated
- A Clinical Study in Healthy Adults Who Sometimes Take Drugs for Pleasure Which Aims to Evaluate Whether GRT0151Y is Likely to be Abused
- A Clinical Study in Healthy Subjects Which Aims to Investigate the Safety, the Tolerability and the Effects of GRT0151Y and How the Compound is Taken up and Excreted From the Body
- A Clinical Study of Mesenchymal Stem Cell Exosomes Nebulizer for the Treatment of ARDS
- A Clinical Study of MR13A9 in Hemodialysis Patients With Pruritus.
- A Clinical Study to Evaluate the Effect of Renal Impairment on the Pharmacokinetics of Cebranopadol
- A Clinical Trial Comparing Buprenorphine Formulations for High Potency Synthetic Opioid Use
- A Clinical Trial to Assess Pharmacokinetic Profiles, Safety and Tolerability of IVL3004 and IVL4002 in Healthy Male Subjects.
- A Comparison of Oxycodone/Naloxone and Oxycodone After Laparoscopic Hysterectomy
- A Comparison of Postoperative Tramadol Versus Acetaminophen With Codeine in Children Undergoing Tonsillectomy
- A Comparison of PR Oxycodone/Naloxone and PR Oxycodone After Cardiac Surgery
- A Comparison of the Addiction Liability of Hydrocodone and Sustained Release Morphine

### Drugs (44)

- Anileridine Kappa opioid receptor agonist
- Anileridine hydrochloride Kappa opioid receptor agonist
- Anileridine phosphate Kappa opioid receptor agonist
- Asimadoline Kappa opioid receptor agonist
- Aticaprant Kappa opioid receptor antagonist
- Axomadol Kappa opioid receptor agonist
- Benzhydrocodone Opioid receptors; mu/kappa/delta agonist
- Benzhydrocodone hydrochloride Opioid receptors; mu/kappa/delta agonist
- [Buprenorphine](https://trialight.com/data/asset/buprenorphine-c075c804-b1a4-4839-84d9-79aa0e258585.md) Kappa opioid receptor agonist
- Buprenorphine hydrochloride Kappa opioid receptor agonist
- Butorphanol Kappa opioid receptor partial agonist
- Butorphanol tartrate Kappa opioid receptor partial agonist
- Cebranopadol Opioid receptors; mu/kappa/delta agonist
- Codeine Opioid receptors; mu/kappa/delta agonist
- Codeine phosphate Opioid receptors; mu/kappa/delta agonist
- Codeine polistirex Opioid receptors; mu/kappa/delta agonist
- Codeine sulfate Opioid receptors; mu/kappa/delta agonist
- Dextromoramide Opioid receptors; mu/kappa/delta agonist
- Dezocine Kappa opioid receptor antagonist
- Difelikefalin Kappa opioid receptor agonist

---

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