These are peptides which are found in the nervous system and act as neuromediators, neurohormones and neurotransmitters. They can be classified as follows

Brain-gut peptides

Hypothalamohypophyseal peptides

  • Hypothalamic release hormones

  • Corticotropin-release factor (CRF)

  • Growth hormone release hormone (GHRH)

  • Luteinizing hormone release hormone (LHRH)

  • Somatostatin

  • Thyrotropin-release hormone

Peptides of neurohypophysis

  • Vasopressin (arginine vasopressin)

  • Oxytocin

Peptides of adenophypophysis

Pro-opiomelanocortin (POMC) derivatives

  • Corticotropin (ACTH)

  • Corticotropin-like intermediate lobe peptide (CLIP)

  • β-endorphins (B-END)

  • β-lipotropin (B-LPH)

  • γ-lipotropin (G-LPH)

  • Met-enkephalon (M-ENK)

  • Leu-enkephalin (L-ENK)

  • α-melanocyte stimulating hormine (α-MSH)

  • γ-melanocyte stimulating hormine (γ-MSH)

Prodynorphin derivatives

  • Neodynorphins α and β (α, β-NE)

  • Dynorphins (DYN) A and B

Other peptides

  • Angiotensin II (ANG-II)

  • Bradykinin

  • Calcitonin-related gene peptide (CGRP)

  • Carnosine

  • Gallinine

  • Natriuretic peptide

  • Neuropeptide Y

  • Sleep peptides

Growth factors

  • Nerve growth factor (NGF)

  • Platelet-derived growth factor (PDGF)

Palkovits classification

(a)     Hypothalamic releasing or inhibiting peptides. They are as follows
Releasing hormones are 1.  Thyroliberin (TRH),  2.  luliberin (LHRH)  3.  somatoliberin (GHRH) 4.  corticoliberin (CRH)  5.  MSH releasing factor (MRE)  6.  FSH releasing factor (FSH-RE) inhibiting hormones are 7. somatostatin (SRIF), 8.  MSH release inhibiting factor (MIF)
(b)     Posterior pituitary hormones   1. vasopressin and 2. oxytocin
(c)     brain-borne pituitary hormones. They are as follows
1.       a-melanotrpin (a-MSH), 2.  melanotropin (b-MSH), 3. corticotrophin (ACTH), 4. lipotropin (LPH), 5. B-endorphin, 6. somatotropin, 7. prolactin, 8. thyrotropin (TSH) 9. follitropin (FSH) and 10. lutropin (LH).
(d)     opioid peptides, 1. B-endorphins  2. endorphin, 3. a-endorphin, 4.
dynorphin, 5. b-neoendorphin, 6. leucine-encephalin and 7 methionine-encephalin. These peptides posses opioid-like activity in addition to being potent neurotransmitters for paraneurons, and neurons of the autonomic and the central nervous system.
(e)     Brain borne gut peptides 1. Insulin, 2. Glucagon, 3. Pancreatic polypeptide, 4. Vasoactive intestinal polypeptide VIP) 5. Motilin, 6. Gastrin-17, 7 gastrin-34, 8. Glicentin, 9. Cholecystokinin, 10. Gastric inhibitory peptide, 11. neurotensin, 12. Substance P  13. Bombesin, 14. Galanin 15. calcitonin gene related peptide, 16. Neuropeptide tyrosine, 17. Porcine intestinal heptacosapeptide, 18. Enteroglucagon, 19. Secretin etc (see chapter on digestive system). Secretin and gastric inhibitory peptide have not been shown conclusively to take part in neuromodulation as is the case with other brain-gut peptides.
(f)      Others Substance P, Neurotensin, angiotensin, bradykinin etc which may or may not be neurotransmitters.
























































Cell Biology
Gross anatomy
Organ integration
Clinical anatomy





Chemical Pathology

Anatomical Pathology





Main Subject Course Links

Anatomy Anesthesia Biochemistry Chemical pathology Community Health
Dermatology ENT Gynecology Hematology Imaging
Medicine Medical microbiology Obstetrics Ophthalmology Pathology
Pediatrics Pharmacology Physiology Psychiatry    Surgery/Orthopedics
eLab eOSCE eProcedures eInvestigations eSchool
eOrgans eLocator Anatomy Museum eDissector eFractures
All diseases eClerking eTreatment eDoctor ePatient




Electronic School of Medicine
Creator: Oluwole Ogunranti