Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Cannabinoid receptor activation acutely increases synaptic vesicle numbers by activating synapsins in human synapses


Cannabis and cannabinoid drugs are central agents that are used widely recreationally and are employed broadly for treating psychiatric conditions. Cannabinoids primarily act by stimulating presynaptic CB1 receptors (CB1Rs), the most abundant G-protein-coupled receptors in brain. CB1R activation decreases neurotransmitter release by inhibiting presynaptic Ca2+ channels and induces long-term plasticity by decreasing cellular cAMP levels. Here we identified an unanticipated additional mechanism of acute cannabinoid signaling in presynaptic terminals that regulates the size of synaptic vesicle pools available for neurotransmitter release. Specifically, we show that activation of CB1Rs in human and mouse neurons rapidly recruits vesicles to nerve terminals by suppressing the cAMP-dependent phosphorylation of synapsins. We confirmed this unanticipated mechanism using conditional deletion of synapsin-1, the predominant synapsin isoform in human neurons, demonstrating that synapsin-1 significantly contributes to the CB1R-dependent regulation of neurotransmission. Interestingly, acute activation of the Gi-DREADD hM4D mimics the effect of CB1R activation in a synapsin-1-dependent manner, suggesting that the control of synaptic vesicle numbers by synapsin-1 phosphorylation is a general presynaptic mechanism of neuromodulation. Thus, we uncovered a CB1R-dependent presynaptic mechanism that rapidly regulates the organization and neurotransmitter release properties of synapses.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Fig. 1: CB1 cannabinoid receptor activation rapidly increases synaptic vesicle numbers in human synapses.
Fig. 2: CB1 receptor activation rapidly alters synaptic vesicle numbers in mouse hippocampal synapses in acute slice preparations.
Fig. 3: CB1 receptor activation regulates SV numbers by a Gi- and synapsin-dependent mechanism.
Fig. 4: CB1 cannabinoid receptors regulate synaptic vesicle mobility by a synapsin-dependent mechanism after stimulation induced sustained neurotransmitter release.
Fig. 5: CB1 cannabinoid receptors regulate synaptic connectivity in neurons by a synapsin-dependent mechanism.


  1. 1.

    Ferland JN, Hurd YL. Deconstructing the neurobiology of cannabis use disorder. Nat Neurosci. 2020;23:600–10.

    CAS  PubMed  Google Scholar 

  2. 2.

    Whiting PF, Wolff RF, Deshpande S, Di Nisio M, Duffy S, Hernandez AV, et al. Cannabinoids for medical use: a systematic review and meta-analysis. JAMA. 2015;313:2456–73.

    CAS  Google Scholar 

  3. 3.

    Katona I, Urban GM, Wallace M, Ledent C, Jung KM, Piomelli D, et al. Molecular composition of the endocannabinoid system at glutamatergic synapses. J Neurosci. 2006;26:5628–37.

    CAS  PubMed  PubMed Central  Google Scholar 

  4. 4.

    Mackie K. Distribution of cannabinoid receptors in the central and peripheral nervous system. Handb Exp Pharmacol. 2005;168: 299–325.

  5. 5.

    Ohno-Shosaku T, Kano M. Endocannabinoid-mediated retrograde modulation of synaptic transmission. Curr Opin Neurobiol. 2014;29:1–8.

    CAS  PubMed  Google Scholar 

  6. 6.

    Castillo PE, Younts TJ, Chavez AE, Hashimotodani Y. Endocannabinoid signaling and synaptic function. Neuron. 2012;76:70–81.

    CAS  PubMed  PubMed Central  Google Scholar 

  7. 7.

    Hirvonen J, Goodwin RS, Li CT, Terry GE, Zoghbi SS, Morse C, et al. Reversible and regionally selective downregulation of brain cannabinoid CB1 receptors in chronic daily cannabis smokers. Mol Psychiatry. 2012;17:642–9.

    CAS  PubMed  Google Scholar 

  8. 8.

    Oviedo A, Glowa J, Herkenham M. Chronic cannabinoid administration alters cannabinoid receptor binding in rat brain: a quantitative autoradiographic study. Brain Res. 1993;616:293–302.

    CAS  PubMed  Google Scholar 

  9. 9.

    Breivogel CS, Childers SR, Deadwyler SA, Hampson RE, Vogt LJ, Sim-Selley LJ. Chronic delta9-tetrahydrocannabinol treatment produces a time-dependent loss of cannabinoid receptors and cannabinoid receptor-activated G proteins in rat brain. J Neurochemistry. 1999;73:2447–59.

    CAS  Google Scholar 

  10. 10.

    González S, Cebeira M, Fernández-Ruiz J. Cannabinoid tolerance and dependence: a review of studies in laboratory animals. Pharm Biochem Behav. 2005;81:300–18.

    Google Scholar 

  11. 11.

    Hirvonen J, Zanotti-Fregonara P, Umhau JC, George DT, Rallis-Frutos D, Lyoo CH, et al. Reduced cannabinoid CB1 receptor binding in alcohol dependence measured with positron emission tomography. Mol Psychiatry. 2013;18:916–21.

    CAS  PubMed  Google Scholar 

  12. 12.

    Neumeister A, Normandin MD, Pietrzak RH, Piomelli D, Zheng MQ, Gujarro-Anton A, et al. Elevated brain cannabinoid CB1 receptor availability in post-traumatic stress disorder: a positron emission tomography study. Mol Psychiatry. 2013;18:1034–40.

    CAS  PubMed  PubMed Central  Google Scholar 

  13. 13.

    Patzke C, Brockmann MM, Dai J, Gan KJ, Grauel MK, Fenske P, et al. Neuromodulator signaling bidirectionally controls vesicle numbers in human synapses. Cell. 2019;179:498–513 e422.

    CAS  PubMed  PubMed Central  Google Scholar 

  14. 14.

    Zhang Y, Pak C, Han Y, Ahlenius H, Zhang Z, Chanda S, et al. Rapid single-step induction of functional neurons from human pluripotent stem cells. Neuron. 2013;78:785–98.

    CAS  PubMed  PubMed Central  Google Scholar 

  15. 15.

    Hosaka M, Hammer RE, Sudhof TC. A phospho-switch controls the dynamic association of synapsins with synaptic vesicles. Neuron. 1999;24:377–87.

    CAS  PubMed  Google Scholar 

  16. 16.

    Südhof TC, Czernik AJ, Kao HT, Takei K, Johnston PA, Horiuchi A, et al. Synapsins: mosaics of shared and individual domains in a family of synaptic vesicle phosphoproteins. Science. 1989;245:1474–80.

    CAS  PubMed  Google Scholar 

  17. 17.

    Monory K, Massa F, Egertová M, Eder M, Blaudzun H, Westenbroek R, et al. The endocannabinoid system controls key epileptogenic circuits in the hippocampus. Neuron. 2006;51:455–66.

    CAS  PubMed  PubMed Central  Google Scholar 

  18. 18.

    Uchigashima M, Yamazaki M, Yamasaki M, Tanimura A, Sakimura K, Kano M, et al. Molecular and morphological configuration for 2-arachidonoylglycerol-mediated retrograde signaling at mossy cell-granule cell synapses in the dentate gyrus. J Neurosci: Off J Soc Neurosci. 2011;31:7700–14.

    CAS  Google Scholar 

  19. 19.

    Caiati MD, Sivakumaran S, Lanore F, Mulle C, Richard E, Verrier D, et al. Developmental regulation of CB1-mediated spike-time dependent depression at immature mossy fiber-CA3 synapses. Sci Rep. 2012;2:285.

    PubMed  PubMed Central  Google Scholar 

  20. 20.

    Patzke C, Südhof TC. The conditional KO approach: Cre/Lox technology in human neurons. Rare Dis. 2016;4:e1131884.

    PubMed  PubMed Central  Google Scholar 

  21. 21.

    Xu J, Pang ZP, Shin OH, Südhof TC. Synaptotagmin-1 functions as a Ca2+ sensor for spontaneous release. Nat Neurosci. 2009;12:759–66.

    CAS  PubMed  PubMed Central  Google Scholar 

  22. 22.

    Kavalali ET. The mechanisms and functions of spontaneous neurotransmitter release. Nat Rev Neurosci. 2015;16:5–16.

    CAS  PubMed  Google Scholar 

  23. 23.

    Darcy KJ, Staras K, Collinson LM, Goda Y. Constitutive sharing of recycling synaptic vesicles between presynaptic boutons. Nat Neurosci. 2006;9:315–21.

    CAS  PubMed  Google Scholar 

  24. 24.

    Staras K, Branco T, Burden JJ, Pozo K, Darcy K, Marra V, et al. A vesicle superpool spans multiple presynaptic terminals in hippocampal neurons. Neuron. 2010;66:37–44.

    CAS  PubMed  PubMed Central  Google Scholar 

  25. 25.

    Fernandez-Alfonso T, Ryan TA. A heterogeneous “resting” pool of synaptic vesicles that is dynamically interchanged across boutons in mammalian CNS synapses. Brain Cell Biol. 2008;36:87–100.

    PubMed  PubMed Central  Google Scholar 

  26. 26.

    Westphal V, Rizzoli SO, Lauterbach MA, Kamin D, Jahn R, Hell SW. Video-rate far-field optical nanoscopy dissects synaptic vesicle movement. Science. 2008;320:246–9.

    CAS  PubMed  Google Scholar 

  27. 27.

    Lee S, Jung KJ, Jung HS, Chang S. Dynamics of multiple trafficking behaviors of individual synaptic vesicles revealed by quantum-dot based presynaptic probe. PloS One. 2012;7:e38045.

    CAS  PubMed  PubMed Central  Google Scholar 

  28. 28.

    Herzog E, Nadrigny F, Silm K, Biesemann C, Helling I, Bersot T, et al. In vivo imaging of intersynaptic vesicle exchange using VGLUT1 Venus knock-in mice. J Neurosci. 2011;31:15544–59.

    CAS  PubMed  PubMed Central  Google Scholar 

  29. 29.

    Czernik AJ, Pang DT, Greengard P. Amino acid sequences surrounding the cAMP-dependent and calcium/calmodulin-dependent phosphorylation sites in rat and bovine synapsin I. Proc Natl Acad Sci USA. 1987;84:7518–22.

    CAS  PubMed  Google Scholar 

  30. 30.

    Jovanovic JN, Sihra TS, Nairn AC, Hemmings HC Jr., Greengard P, Czernik AJ. Opposing changes in phosphorylation of specific sites in synapsin I during Ca2+-dependent glutamate release in isolated nerve terminals. J Neurosci. 2001;21:7944–53.

    CAS  PubMed  PubMed Central  Google Scholar 

  31. 31.

    Ramírez-Franco J, Bartolomé-Martín D, Alonso B, Torres M, Sánchez-Prieto J. Cannabinoid type 1 receptors transiently silence glutamatergic nerve terminals of cultured cerebellar granule cells. PloS One. 2014;9:e88594.

    PubMed  PubMed Central  Google Scholar 

  32. 32.

    García-Morales V, Montero F, Moreno-López B. Cannabinoid agonists rearrange synaptic vesicles at excitatory synapses and depress motoneuron activity in vivo. Neuropharmacology. 2015;92:69–79.

    PubMed  Google Scholar 

  33. 33.

    Imig C, Min SW, Krinner S, Arancillo M, Rosenmund C, Südhof TC, et al. The morphological and molecular nature of synaptic vesicle priming at presynaptic active zones. Neuron. 2014;84:416–31.

    CAS  PubMed  Google Scholar 

  34. 34.

    Alabi AA, Tsien RW. Synaptic vesicle pools and dynamics. Cold Spring Harb Perspect Biol. 2012;4:a013680.

    PubMed  PubMed Central  Google Scholar 

  35. 35.

    Rosahl TW, Spillane D, Missler M, Herz J, Selig DK, Wolff JR, et al. Essential functions of synapsins I and II in synaptic vesicle regulation. Nature. 1995;375:488–93.

    CAS  PubMed  Google Scholar 

  36. 36.

    Pieribone VA, Shupliakov O, Brodin L, Hilfiker-Rothenfluh S, Czernik AJ, Greengard P. Distinct pools of synaptic vesicles in neurotransmitter release. Nature. 1995;375:493–7.

    CAS  PubMed  Google Scholar 

  37. 37.

    Acuna C, Liu X, Südhof TC. How to make an active zone: unexpected universal functional redundancy between RIMs and RIM-BPs. Neuron. 2016;91:792–807.

    CAS  PubMed  PubMed Central  Google Scholar 

  38. 38.

    Wang SSH, Held RG, Wong MY, Liu C, Karakhanyan A, Kaeser PS. Fusion competent synaptic vesicles persist upon active zone disruption and loss of vesicle docking. Neuron. 2016;91:777–91.

    PubMed  PubMed Central  Google Scholar 

  39. 39.

    Patzke C, Acuna C, Giam LR, Wernig M, Südhof TC. Conditional deletion of L1CAM in human neurons impairs both axonal and dendritic arborization and action potential generation. J Exp Med. 2016;213:499–515.

    CAS  PubMed  PubMed Central  Google Scholar 

  40. 40.

    Chung K, Wallace J, Kim SY, Kalyanasundaram S, Andalman AS, Davidson TJ, et al. Structural and molecular interrogation of intact biological systems. Nature. 2013;497:332–7.

    CAS  PubMed  PubMed Central  Google Scholar 

  41. 41.

    Dai J, Chen P, Tian H, Sun J. Spontaneous vesicle release is not tightly coupled to voltage-gated calcium channel-mediated Ca2+ influx and is triggered by a Ca2+ sensor other than synaptotagmin-2 at the juvenile mice Calyx of held synapses. J Neurosci: Off J Soc Neurosci. 2015;35:9632–7.

    CAS  Google Scholar 

  42. 42.

    Rosenmund C, Stevens CF. Definition of the readily releasable pool of vesicles at hippocampal synapses. Neuron. 1996;16:1197–207.

    CAS  PubMed  Google Scholar 

  43. 43.

    Watanabe S, Rost BR, Camacho-Perez M, Davis MW, Sohl-Kielczynski B, Rosenmund C, et al. Ultrafast endocytosis at mouse hippocampal synapses. Nature. 2013;504:242–7.

    CAS  PubMed  PubMed Central  Google Scholar 

Download references


This work was supported by grants from the NIH (MH092931 and AG010770 to TCS), from the German Research Council (DFG PA 2110/1-1 to CP), and the DFG Reinhart Koselleck Project and SFB958 (to CR). We thank Drs Louise Giam and Xiao Du for sharing their unpublished RNA-sequencing data, Dr Sean Aric Merrill for helping with STORM microscopy, Dr Amber Nabet and Sofia Essayan-Perez for advice.

Author information




CP and TCS conceived the study. CP, JD, and MMB, designed, performed, and analyzed most of the experiments. ZS, PF, and CR contributed to specific experiments. CP and TCS prepared the manuscript with input from all authors.

Corresponding author

Correspondence to Christopher Patzke.

Ethics declarations

Conflict of interest

The authors declare no competing interests.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Patzke, C., Dai, J., Brockmann, M.M. et al. Cannabinoid receptor activation acutely increases synaptic vesicle numbers by activating synapsins in human synapses. Mol Psychiatry (2021).

Download citation


Quick links