Vol 58, No 2 (2020)
Original paper
Published online: 2020-06-02

open access

Page views 1092
Article views/downloads 605
Get Citation

Connect on Social Media

Connect on Social Media

A close neuroanatomical relationship between the enkephalinergic (methionine-enkephalin) and tachykininergic (substance P) systems in the alpaca diencephalon

Pablo Sánchez1, Manuel Lisardo Sánchez1, Arturo Mangas12, Luís Ángel Aguilar3, Rafael Coveñas1
Pubmed: 32412087
Folia Histochem Cytobiol 2020;58(2):135-146.


Introduction. In the alpaca diencephalon, the distribution of immunoreactive cell bodies and fibers containing methionine-enkephalin (MET) or substance P (SP) has been studied.

Material and methods. The immunohistochemical study was performed by standard method on the diencephalon of four male alpacas that lived at sea level.

Results. Nerve fibers containing MET or SP were widely distributed in the thalamus and hypothalamus. METand SP-immunoreactive fibers showed a similar distribution in the whole diencephalon. Immunoreactive cell bodies containing MET or SP were only observed in the hypothalamus. The distribution of MET-immunoreactive cell bodies was more widespread than that observed for cell bodies containing SP.

Conclusions. A close neuroanatomical relationship between the tachykininergic (SP) and enkephalinergic (MET) systems was observed in the whole diencephalon suggestive of the existence of multiple physiological interactions between both systems.

Article available in PDF format

View PDF Download PDF file


  1. Bux F, Bhagwandin A, Fuxe K, et al. Organization of cholinergic, putative catecholaminergic and serotonergic nuclei in the diencephalon, midbrain and pons of sub-adult male giraffes. J Chem Neuroanat. 2010; 39(3): 189–203.
  2. Coveñas R, Mangas A, Narváez JA. Introduction to neuropeptides. In: Coveñas R, Mangas A, Narváez JA, eds. Focus on neuropeptide research. Trivandrum: Transworld Research Network; 2007: 1-26.
  3. Ebner K, Singewald N. The role of substance P in stress and anxiety responses. Amino Acids. 2006; 31(3): 251–272.
  4. Ebner K, Muigg P, Singewald G, et al. Substance P in stress and anxiety: NK-1 receptor antagonism interacts with key brain areas of the stress circuitry. Ann N Y Acad Sci. 2008; 1144: 61–73.
  5. Graefe S, Mohiuddin SS. Biochemistry, substance P. Treasure Island (FL): StatPearls Publishing; 2020. PMID: 32119470.
  6. Hertler B, Hosp JA, Blanco MB, et al. Substance P signalling in primary motor cortex facilitates motor learning in rats. PLoS One. 2017; 12(12): e0189812.
  7. Mashaghi A, Marmalidou A, Tehrani M, et al. Neuropeptide substance P and the immune response. Cell Mol Life Sci. 2016; 73(22): 4249–4264.
  8. Ribeiro-da-Silva A, Hökfelt T. Neuroanatomical localisation of Substance P in the CNS and sensory neurons. Neuropeptides. 2000; 34(5): 256–271.
  9. Ebrahimi S, Javid H, Alaei A, et al. New insight into the role of substance P/neurokinin-1 receptor system in breast cancer progression and its crosstalk with microRNAs. Clin Genet. 2020 [Epub ahead of print].
  10. Coveñas R, Mangas A, Medina LE, et al. Mapping of somatostatin-28 (1-12) in the alpaca diencephalon. J Chem Neuroanat. 2011; 42(1): 89–98.
  11. Coveñas R, Sánchez ML, Mangas A, et al. Mapping of CGRP in the alpaca diencephalon. J Chem Neuroanat. 2012; 45(1-2): 36–44.
  12. Manso B, Sánchez ML, Medina LE, et al. Immunohistochemical mapping of pro-opiomelanocortin- and pro-dynorphin-derived peptides in the alpaca (Lama pacos) diencephalon. J Chem Neuroanat. 2014; 59-60: 36–50.
  13. Marcos P, Arroyo-Jiménez MM, Lozano G, et al. Mapping of tyrosine hydroxylase in the diencephalon of alpaca (Lama pacos) and co-distribution with somatostatin-28 (1-12). J Chem Neuroanat. 2013; 50-51: 66–74.
  14. Sánchez ML, Mangas A, Medina LE, et al. Immunohistochemical mapping of neurotensin in the alpaca diencephalon. Folia Histochem Cytobiol. 2018; 56(1): 49–58.
  15. Palkovits M. Neuropeptides in the brain. In: Ganong WF, Martini L, eds. Frontiers in Neuroendocrinology. New York: Raven Press. ; 1988: 1–44.
  16. Conrath M, Covenas R, Romo R, et al. Distribution of Met-enkephalin immunoreactive fibres in the thalamus of the cat. Neurosci Lett. 1986; 65(3): 299–303.
  17. Coveñas R, Burgos C, Conrath M. Immunocytochemical study of Met-enkephalin-like cell bodies in the cat hypothalamus. Neurosci Res. 1988; 5(4): 353–360.
  18. Burgos C, Aguirre JA, Alonso JR, et al. Immunocytochemical study of substance P-like fibres and cell bodies in the cat diencephalon. J Hirnforsch. 1988; 29(6): 651–657.
  19. Duque-Díaz E, Díaz-Cabiale Z, Narváez JA, et al. Mapping of enkephalins and adrenocorticotropic hormone in the squirrel monkey brainstem. Anat Sci Int. 2017; 92(2): 275–292.
  20. Duque-Díaz E, Coveñas R. Distribution of somatostatin-28 (1-12), calcitonin gene-related peptide, and substance P in the squirrel monkey brainstem: an immunocytochemical study. Anat Sci Int. 2019; 94(1): 86–100.
  21. Mangas A, Yajeya J, Gonzalez N, et al. Detection of pantothenic acid-immunoreactive neurons in the rat lateral septal nucleus by a newly developed antibody. Folia Histochem Cytobiol. 2016; 54(4): 186–192.
  22. Pesini P, Pego-Reigosa R, Tramu G, et al. Distribution of met-enkephalin immunoreactivity in the diencephalon and the brainstem of the dog. J Chem Neuroanat. 2000; 19(4): 243–258.
  23. Samsam M, Coveñas R, Csillik B, et al. Depletion of substance P, neurokinin A and calcitonin gene-related peptide from the contralateral and ipsilateral caudal trigeminal nucleus following unilateral electrical stimulation of the trigeminal ganglion; a possible neurophysiological and neuroanatomical link to generalized head pain. J Chem Neuroanat. 2001; 21(2): 161–169.
  24. Sánchez ML, Vecino E, Coveñas R. Distribution of methionine-enkephalin in the minipig brainstem. J Chem Neuroanat. 2013; 50-51: 1–10.
  25. Fuxe K, Agnati LF, et al. Coveñas R, Volume transmission in transmitter peptide costoring neurons in the medulla oblongata. In: Barraco IRA, ed. Nucleus of the Solitary Tract. Boca Raton: CRC Press. ; 1994: 74–89.
  26. Fuxe K, Borroto-Escuela DO. Volume transmission and receptor-receptor interactions in heteroreceptor complexes: understanding the role of new concepts for brain communication. Neural Regen Res. 2016; 11(8): 1220–1223.
  27. Nusbaum M, Blitz D, Marder E. Functional consequences of neuropeptide and small-molecule co-transmission. Nature Reviews Neuroscience. 2017; 18(7): 389–403.
  28. Ralston HJ. Pain and the primate thalamus. Prog Brain Res. 2005; 149: 1–10.
  29. Li JN, Sun Yi, Ji SL, et al. Collateral Projections from the Medullary Dorsal Horn to the Ventral Posteromedial Thalamic Nucleus and the Parafascicular Thalamic Nucleus in the Rat. Neuroscience. 2019; 410: 293–304.
  30. Urstadt KR, Berridge KC. Optogenetic mapping of feeding and self-stimulation within the lateral hypothalamus of the rat. PLoS One. 2020; 15(1): e0224301.
  31. Szymusiak R, McGinty D. Hypothalamic regulation of sleep and arousal. Ann N Y Acad Sci. 2008; 1129: 275–286.
  32. Coveñas R, de León M, Cintra A, et al. Coexistence of c-Fos and glucocorticoid receptor immunoreactivities in the CRF immunoreactive neurons of the paraventricular hypothalamic nucleus of the rat after acute immobilization stress. Neurosci Lett. 1993; 149(2): 149–152.
  33. Koinuma S, Asakawa T, Nagano M, et al. Regional circadian period difference in the suprachiasmatic nucleus of the mammalian circadian center. Eur J Neurosci. 2013; 38(6): 2832–2841.
  34. Blair HT, Cho J, Sharp PE. Role of the lateral mammillary nucleus in the rat head direction circuit: a combined single unit recording and lesion study. Neuron. 1998; 21(6): 1387–1397.
  35. Bouras C, Taban CH, Constantinidis J. Mapping of enkephalins in human brain. An immunohistofluorescence study on brains from patients with senile and presenile dementia. Neuroscience. 1984; 12(1): 179–190.
  36. Bouras C, Vallet PG, Dobrinov H, et al. Substance P neuronal cell bodies in the human brain: complete mapping by immunohistofluorescence. Neurosci Lett. 1986; 69(1): 31–36.
  37. Covenas R, Romo R, Cheramy A, et al. Immunocytochemical study of enkephalin-like cell bodies in the thalamus of the cat. Brain Res. 1986; 377(2): 355–361.
  38. Coveñas R, Alonso JR, Conrath M. Immunocytochemical study of enkephalin-like cell bodies in the thalamus of the rat. Brain Res Bull. 1989; 23(4-5): 277–281.
  39. Finley JC, Maderdrut JL, Petrusz P. The immunocytochemical localization of enkephalin in the central nervous system of the rat. J Comp Neurol. 1981; 198(4): 541–565.
  40. Haber SN, Wolfe DP, Groenewegen HJ, et al. The distribution of enkephalin immunoreactive fibers and terminals in the monkey central nervous system: an immunohistochemical study. Neuroscience. 1982; 7(5): 1049–1095.
  41. Hökfelt T, Elde R, Johansson O, et al. The distribution of enkephalin-immunoreactive cell bodies in the rat central nervous system. Neurosci Lett. 1977; 5(1-2): 25–31.
  42. Inagaki S, Parent A. Distribution of enkephalin-immunoreactive neurons in the forebrain and upper brainstem of the squirrel monkey. Brain Res. 1985; 359(1-2): 267–280.
  43. Ljungdahl A, Hökfelt T, Nilsson G. Distribution of substance P-like immunoreactivity in the central nervous system of the rat--I. Cell bodies and nerve terminals. Neuroscience. 1978; 3(10): 861–943.
  44. Merchenthaler I, Maderdrut JL, Altschuler RA, et al. Immunocytochemical localization of proenkephalin-derived peptides in the central nervous system of the rat. Neuroscience. 1986; 17(2): 325–348.
  45. Sar M, Stumpf WE, Miller RJ, et al. Immunohistochemical localization of enkephalin in rat brain and spinal cord. J Comp Neurol. 1978; 182(1): 17–37.