Biomaterial Database

Mechanism of lower esophageal sphincter stimulation by bombesin in the opossum. 1979

A K Mukhopadhyay, and M Kunnemann

Effect of intravenously administered bombesin has been studied on the in vivo and in vitro motor function of the lower esophageal sphincter (LES) of the opossum. Intraesophageal pressures were monitored by an assembly of polyvinyl catheters attached to pressure transducers and a recorder. The catheters were continuously perfused with bubble-free water. Intravenous administration of 5, 10, 30, 50, and 100 ng/kg bombesin stimulated the LES 4, 34, 106, 148, and 130%, respectively, above control values. Atropine and hexamethonium did not antagonize the response of the LES to bombesin. Tetrodotoxin, phentolamine, and reserpine all significantly antagonized the response of the LES to bombesin. The LES stimulatory effect of bombesin injected locally in the left gastric artery (LGA) was antagonized significantly by local administration of phentolamine in the LGA. Experiments performed in vitro (25 ml baths containing oxygenated Krebs solution) showed that bombesin (10(-9) M) increased the tone of LES strips, and the effect was antagonized by phentolamine (10(-6) M). Serum gastrin concentrations increased significantly only 15 min after bombesin administration. It is concluded that bombesin is a potent stimulant of the LES. The mechanism of stimulation involves a direct effect on the smooth muscle as well as an indirect one by an effect on the postganglionic adrenergic neurons releasing norepinephrine.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008365	Manometry	Measurement of the pressure or tension of liquids or gases with a manometer.	Tonometry,Manometries
D009893	Opossums	New World marsupials of the family Didelphidae. Opossums are omnivorous, largely nocturnal and arboreal MAMMALS, grow to about three feet in length, including the scaly prehensile tail, and have an abdominal pouch in which the young are carried at birth.	Didelphidae,Opossum
D010455	Peptides	Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are considered to be larger versions of peptides that can form into complex structures such as ENZYMES and RECEPTORS.	Peptide,Polypeptide,Polypeptides
D010646	Phentolamine	A nonselective alpha-adrenergic antagonist. It is used in the treatment of hypertension and hypertensive emergencies, pheochromocytoma, vasospasm of RAYNAUD DISEASE and frostbite, clonidine withdrawal syndrome, impotence, and peripheral vascular disease.	Fentolamin,Phentolamine Mesilate,Phentolamine Mesylate,Phentolamine Methanesulfonate,Phentolamine Mono-hydrochloride,Regitine,Regityn,Rogitine,Z-Max,Mesilate, Phentolamine,Mesylate, Phentolamine,Methanesulfonate, Phentolamine,Mono-hydrochloride, Phentolamine,Phentolamine Mono hydrochloride
D011941	Receptors, Adrenergic	Cell-surface proteins that bind epinephrine and/or norepinephrine with high affinity and trigger intracellular changes. The two major classes of adrenergic receptors, alpha and beta, were originally discriminated based on their cellular actions but now are distinguished by their relative affinity for characteristic synthetic ligands. Adrenergic receptors may also be classified according to the subtypes of G-proteins with which they bind; this scheme does not respect the alpha-beta distinction.	Adrenergic Receptors,Adrenoceptor,Adrenoceptors,Norepinephrine Receptor,Receptors, Epinephrine,Receptors, Norepinephrine,Adrenergic Receptor,Epinephrine Receptors,Norepinephrine Receptors,Receptor, Adrenergic,Receptor, Norepinephrine
D011978	Receptors, Nicotinic	One of the two major classes of cholinergic receptors. Nicotinic receptors were originally distinguished by their preference for NICOTINE over MUSCARINE. They are generally divided into muscle-type and neuronal-type (previously ganglionic) based on pharmacology, and subunit composition of the receptors.	Nicotinic Acetylcholine Receptors,Nicotinic Receptors,Nicotinic Acetylcholine Receptor,Nicotinic Receptor,Acetylcholine Receptor, Nicotinic,Acetylcholine Receptors, Nicotinic,Receptor, Nicotinic,Receptor, Nicotinic Acetylcholine,Receptors, Nicotinic Acetylcholine
D012110	Reserpine	An alkaloid found in the roots of Rauwolfia serpentina and R. vomitoria. Reserpine inhibits the uptake of norepinephrine into storage vesicles resulting in depletion of catecholamines and serotonin from central and peripheral axon terminals. It has been used as an antihypertensive and an antipsychotic as well as a research tool, but its adverse effects limit its clinical use.	Raunervil,Raupasil,Rausedil,Rausedyl,Serpasil,Serpivite,V-Serp,V Serp
D001839	Bombesin	A tetradecapeptide originally obtained from the skins of toads Bombina bombina and B. variegata. It is also an endogenous neurotransmitter in many animals including mammals. Bombesin affects vascular and other smooth muscle, gastric secretion, and renal circulation and function.	Bombesin 14,Bombesin Dihydrochloride,Dihydrochloride, Bombesin
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response