Compound 46, designated as MOR agonist-2, serves as a D3R antagonist and a MOR agonist with respective K i values of 7.26 nM and 564 nM. This compound holds potential for analgesic effects attributed to its partial agonism at MOR and may decrease opioid misuse liability owing to its antagonistic action at D3R [1].

CSD-CH2(1,8)-NH2 is a selective and competitive kappa-opioid receptor (KOR) antagonist with a K i of 6.8 nM. It inhibits calcium mobilization in dorsal root ganglion (DRG) neurons and antagonizes the antinociceptive effect of U50,488, making it useful for research into neuropsychiatric disorders [1].

Hemorphin-7 acetate is a hemorphin peptide, an endogenous opioid peptide derived from the β-chain of hemoglobin. Hemorphin peptides exhibits antinociceptive and antihypertensive activities, activating opioid receptors and inhibiting angiotensin-converting enzyme (ACE).

Matrine (Vegard), an alkaloid isolated from the Sophora genus, acts as a kappa opioid receptor agonist.

Apitegromab (SRK-015) is a new myostatin inhibitor, an antibody targeting myostatin precursor, which can be used to study neuromuscular diseases including spinal muscular atrophy.