Bombesin is a 14-

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha ...

peptide Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. ...

originally isolated from the

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...

of the

European fire-bellied toad The European fire-bellied toad (''Bombina bombina'') is a species of fire-bellied toad native to eastern parts of mainland Europe, where it can be found near waterbodies such as ponds and marshes. It is known for its red colored belly used to war ...

(''Bombina bombina'') by Vittorio Erspamer ''et al.'' and named after its source. NIHMSID 45053. It has two known homologs in

mammals Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fu ...

called

neuromedin B Neuromedin B (NMB) is a bombesin-related peptide in mammals. It was originally purified from pig spinal cord, and later shown to be present in human central nervous system and gastrointestinal tract. Sequence The sequence of the C-terminal de ...

and gastrin-releasing peptide. It stimulates

gastrin Gastrin is a peptide hormone that stimulates secretion of gastric acid (HCl) by the parietal cells of the stomach and aids in gastric motility. It is released by G cells in the pyloric antrum of the stomach, duodenum, and the pancreas. Gastrin ...

release from G cells. It activates three different

G-protein G proteins, also known as guanine nucleotide-binding proteins, are a family of proteins that act as molecular switches inside cells, and are involved in transmitting signals from a variety of stimuli outside a cell to its interior. Their ...

-coupled receptors known as BBR1, -2, and -3. It also activates these receptors in the

brain The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head ( cephalization), usually near organs for special ...

. Together with

cholecystokinin Cholecystokinin (CCK or CCK-PZ; from Greek ''chole'', "bile"; ''cysto'', "sac"; ''kinin'', "move"; hence, ''move the bile-sac (gallbladder)'') is a peptide hormone of the gastrointestinal system responsible for stimulating the digestion of fat an ...

, it is the second major source of

negative feedback Negative feedback (or balancing feedback) occurs when some function of the output of a system, process, or mechanism is fed back in a manner that tends to reduce the fluctuations in the output, whether caused by changes in the input or by othe ...

signals that stop eating behaviour. Bombesin is also a

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

marker for small cell carcinoma of lung, gastric cancer, pancreatic cancer, and

neuroblastoma Neuroblastoma (NB) is a type of cancer that forms in certain types of nerve tissue. It most frequently starts from one of the adrenal glands but can also develop in the neck, chest, abdomen, or spine. Symptoms may include bone pain, a lump i ...

Receptors

The anuran receptor homologue is termed (). Iwabuchi ''et al.'' 2003 discovered a

chicken The chicken (''Gallus gallus domesticus'') is a domestication, domesticated junglefowl species, with attributes of wild species such as the grey junglefowl, grey and the Ceylon junglefowl that are originally from Southeastern Asia. Rooster ...

(''Gallus domesticus'') receptor which is homologous to both the and fBB₄ and so they named it .

Effects

Erspamer 1988 finds bombesin has a similar effect on the chicken to ranatensin, unreliably increasing or decreasing blood pressure.

References

{{Neuropeptides Neuropeptides Pyrrolidones Tryptamines Imidazoles

Receptors

Effects

See also

References