Biomaterial Database

Spontaneous release of endogenous 5-hydroxytryptamine and 5-hydroxyindoleacetic acid from the isolated vascularly perfused ileum of the guinea-pig. 1987

H Schwörer, and K Racké, and H Kilbinger

The spontaneous release of 5-hydroxytryptamine and its metabolite 5-hydroxyindoleacetic acid from the enterochromaffin cells of the small intestine into the portal circulation was investigated in vitro using the vascularly perfused ileum of the guinea-pig. The release of 5-hydroxytryptamine decreased by 70% in a calcium-free medium and by 35% in the presence of tetrodotoxin. Inhibition of monoamine oxidase activity by pargyline (100 microM) had no effect on the spontaneous release of 5-hydroxytryptamine although it caused a 75% reduction in the outflow of 5-hydroxyindoleacetic acid. Imipramine (1 microM), an inhibitor of neuronal uptake of 5-hydroxytryptamine, reduced the 5-hydroxyindoleacetic acid outflow by 57% and increased the release of 5-hydroxytryptamine by 66%. The combination of both drugs showed no additional effect. The tissue content of 5-hydroxytryptamine and its metabolite was not changed after perfusion with the precursor L-tryptophan or monofluoromethyldopa, an inhibitor of the L-aromatic amino acid decarboxylase. The results show that the spontaneous release of 5-hydroxytryptamine and its metabolite reflects largely calcium-dependent exocytotic release of the amine. "Neuronal uptake" (into aminergic and/or enterochromaffin cells) followed by deamination appears to be the main pathway of 5-hydroxytryptamine catabolism in the guinea-pig ileum.

UI	MeSH Term	Description	Entries
D007082	Ileum	The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.
D007099	Imipramine	The prototypical tricyclic antidepressant. It has been used in major depression, dysthymia, bipolar depression, attention-deficit disorders, agoraphobia, and panic disorders. It has less sedative effect than some other members of this therapeutic group.	Imidobenzyle,Imizin,4,4'-Methylenebis(3-hydroxy-2-naphthoic acid)-3-(10,11-dihydro-5H-dibenzo(b,f)azepin-5-yl)-N,N-dimethyl-1-propanamine (1:2),Imipramine Hydrochloride,Imipramine Monohydrochloride,Imipramine Pamoate,Janimine,Melipramine,Norchlorimipramine,Pryleugan,Tofranil
D008297	Male		Males
D008750	Methyldopa	An alpha-2 adrenergic agonist that has both central and peripheral nervous system effects. Its primary clinical use is as an antihypertensive agent.	Methyldopate,alpha-Methyldopa,Aldomet,Alphamethyldopa,Apo-Methyldopa,Dopamet,Dopegit,Dopegyt,Dopergit,Hydopa,Meldopa,Nu-Medopa,Sembrina,alpha-Methyl-L-Dopa,Apo Methyldopa,Nu Medopa,alpha Methyl L Dopa,alpha Methyldopa
D009197	Myenteric Plexus	One of two ganglionated neural networks which together form the ENTERIC NERVOUS SYSTEM. The myenteric (Auerbach's) plexus is located between the longitudinal and circular muscle layers of the gut. Its neurons project to the circular muscle, to other myenteric ganglia, to submucosal ganglia, or directly to the epithelium, and play an important role in regulating and patterning gut motility. (From FASEB J 1989;3:127-38)	Auerbach's Plexus,Auerbach Plexus,Auerbachs Plexus,Plexus, Auerbach's,Plexus, Myenteric
D010293	Pargyline	A monoamine oxidase inhibitor with antihypertensive properties.	Pargyline Hydrochloride,Hydrochloride, Pargyline
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
D011169	Portal Vein	A short thick vein formed by union of the superior mesenteric vein and the splenic vein.	Portal Veins,Vein, Portal,Veins, Portal
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea