Mechanism of Action
Neurotensin Receptor Activation
Xenopsin binds neurotensin receptors (NTR1 and NTR2) through its C-terminal sequence, which shares the Trp-Ile-Leu element found in neurotensin. NTR1 activation through Gq and Gi coupling modulates dopamine signaling, produces analgesia, and lowers body temperature. These effects are blocked by neurotensin receptor antagonists.
Dual Activity
Xenopsin also has some tachykinin receptor interaction properties. Its structural features bridge the neurotensin and tachykinin families, making it an interesting pharmacological tool for probing the binding sites of both receptor classes.
Research Summary
Neurotensin Receptor Pharmacology
PreclinicalXenopsin provided early evidence for neurotensin receptor multiplicity. Its differential effects in various tissue preparations and central regions suggested that different NTR subtypes have distinct distribution patterns. These studies contributed to the eventual molecular cloning and characterization of NTR1, NTR2, and NTR3.
Antipsychotic-Like Properties
PreclinicalLike neurotensin and neuromedin N, xenopsin reduces dopamine-mediated behaviors in rodent models. ICV administration decreases apomorphine-induced stereotypy and hyperlocomotion, consistent with dopamine antagonism in mesolimbic circuits. This suggests potential relevance to psychosis research.
Calculate your Xenopsin dose Vial strength, BAC water, exact syringe draw in IU. Free, no signup. Open Calc →
Research Protocols
| Goal | Dose | Frequency | Route |
|---|---|---|---|
| NTR binding | 1-1000 nM | Single | Receptor binding assay |
| Hypothermia/analgesia | 1-10 nmol ICV | Single | Intracerebroventricular |
Research tool only. No therapeutic applications established.
Interactions
Safety Profile
Xenopsin produces hypotension and hypothermia. Research use only. No human safety data. Neurotensin receptor activation in humans would require careful cardiovascular monitoring.
References
- [1]Araki K et al. (1973). Xenopsin: the neurotensin-like octapeptide from Xenopus laevis skin. Chemical and Pharmaceutical Bulletin, 21(12), 2801-2804.
- [2]Quirion R et al. (1980). Neurotensin is a potent inhibitor of (3H)-dopamine binding in the rat brain. Nature, 290(5810), 449-451.