Heteroreceptor

A generalized neuron containing heteroreceptors showing the release of different neurotransmitters than the heteroreceptor ligand.

A heteroreceptor is a receptor located in the cell membrane of a neuron, regulating the synthesis and/or the release of mediators other than its own ligand. ^[1] Heteroreceptors play a crucial role in modulating neurotransmitter systems and are often targets for therapeutic drugs. By influencing the activity of other neurotransmitters, the receptors contribute to the complex regulation of neural communication and have been implicated in various physiological and pathological processes. ^[2]

Heteroreceptors may be located in any part of the Neuron including the dendrites, the cell body, the axon, or the axon terminals.

Heteroreceptors respond to neurotransmitters, neuromodulators, or neurohormones released from adjacent neurons or cells; they are opposite to autoreceptors, which are sensitive only to neurotransmitters or hormones released by the cell in whose wall they are embedded. ^[3]

Examples

• Norepinephrine can influence the release of acetylcholine from parasympathetic neurons by acting on α2 adrenergic (α_2A, α_2B, and α_2C) heteroreceptors. ^[4] These effects are related to analgesia, sedation, hypothermia. ^[5]
• Acetylcholine can influence the release of norepinephrine from sympathetic neurons by acting on muscarinic-2 and muscarinic-4 heteroreceptors.
• CB1 negatively modulates the release of GABA ^{[6] [7]} and glutamate, ^[8] playing a crucial role in maintaining a homeostasis between excitatory and inhibitory transmission.
• Glutamate released from an excitatory neuron escapes from the synaptic cleft and preferentially affects mGluR III receptors on the presynaptic terminals of interneurons. Glutamate spillover leads to inhibition of GABA release, modulating GABAergic transmission. ^{[9] [10]}

See also

• Autoreceptor

References

1. Laduron, Pierre M. (February 1985). "Presynaptic heteroreceptors in regulation of neuronal transmission" . Biochemical Pharmacology. 34 (4): 467–470. doi:10.1016/0006-2952(85)90176-5. PMID   2578794.
2. Fuxe, Kjell; Borroto-Escuela, Dasiel O. (2016-01-01). "Heteroreceptor Complexes and their Allosteric Receptor–Receptor Interactions as a Novel Biological Principle for Integration of Communication in the CNS: Targets for Drug Development". Neuropsychopharmacology. 41 (1): 380–382. doi:10.1038/npp.2015.244. ISSN   1740-634X. PMC   4677137 . PMID   26657959.
3. Schlicker, E.; Malinowska, B.; Kathmann, M.; Göthert, M. (1994-03-04). "Modulation of neurotransmitter release via histamine H 3 heteroreceptors" . Fundamental & Clinical Pharmacology. 8 (2): 128–137. doi:10.1111/j.1472-8206.1994.tb00789.x. ISSN   0767-3981.
4. Ma, D.; Rajakumaraswamy, N.; Maze, M. (2004). "2-Adrenoceptor agonists: Shedding light on neuroprotection?". British Medical Bulletin. 71: 77–92. doi: 10.1093/bmb/ldh036 . PMID   15684247.
5. Gilsbach, Ralf; Hein, Lutz (January 2012). "Are the pharmacology and physiology of α 2 adrenoceptors determined by α 2 -heteroreceptors and autoreceptors respectively?". British Journal of Pharmacology. 165 (1): 90–102. doi:10.1111/j.1476-5381.2011.01533.x. ISSN   0007-1188. PMC   3252969 . PMID   21658028.
6. Katona, I.; Sperlágh, B.; Sík, A.; Käfalvi, A.; Vizi, E. S.; MacKie, K.; Freund, T. F. (1999). "Presynaptically located CB1 cannabinoid receptors regulate GABA release from axon terminals of specific hippocampal interneurons". The Journal of Neuroscience. 19 (11): 4544–4558. doi: 10.1523/JNEUROSCI.19-11-04544.1999 . PMC   6782612 . PMID   10341254.
7. Sousa, V. C.; Assaife-Lopes, N. L.; Ribeiro, J. A.; Pratt, J. A.; Brett, R. R.; Sebastião, A. M. (2010). "Regulation of Hippocampal Cannabinoid CB1 Receptor Actions by Adenosine A1 Receptors and Chronic Caffeine Administration: Implications for the Effects of Δ9-Tetrahydrocannabinol on Spatial Memory". Neuropsychopharmacology. 36 (2): 472–487. doi:10.1038/npp.2010.179. PMC   3055664 . PMID   20927050.
8. Hoffman, A. F.; Laaris, N.; Kawamura, M.; Masino, S. A.; Lupica, C. R. (2010). "Control of Cannabinoid CB1 Receptor Function on Glutamate Axon Terminals by Endogenous Adenosine Acting at A1 Receptors". Journal of Neuroscience. 30 (2): 545–555. doi:10.1523/JNEUROSCI.4920-09.2010. PMC   2855550 . PMID   20071517.
9. Semyanov, A; Kullmann, D. M. (2000). "Modulation of GABAergic signaling among interneurons by metabotropic glutamate receptors". Neuron. 25 (3): 663–72. doi: 10.1016/s0896-6273(00)81068-5 . PMID   10774733.
10. Kullmann, D. M.; Semyanov, A (2002). "Glutamatergic modulation of GABAergic signaling among hippocampal interneurons: Novel mechanisms regulating hippocampal excitability". Epilepsia. 43 (Suppl 5): 174–8. doi:10.1046/j.1528-1157.43.s.5.12.x. PMID   12121316. S2CID   19781597.