Participation of nicotinic receptor in hormone release from isolated rat islets of Langerhans.
Pancreatic hormone release is generally thought to be regulated through adrenergic as well as muscarinic receptors. We have previously observed possible nicotinic involvement in insulin release. In the present study, we incubated isolated rat islets for 60 min with various concentrations of atropine (a muscarinic receptor blocker), alpha-bungarotoxin (alpha-Btx, a nicotinic receptor blocker), and anti-acetylcholine receptor antibody (IgG) (anti-Ach.R.Ab) obtained from a patient with myasthenia gravis. Atropine suppressed insulin release, and alpha-Btx and anti-Ach.R.Ab potentiated it; atropine did not suppress glucagon release, while alpha-Btx and anti-Ach.R.Ab raised it. None of these agents influenced somatostatin release. These observations suggest that muscarinic as well as nicotinic receptors influence insulin release, as nicotinic receptors do glucagon release. Neither nicotinic nor muscarinic receptors seem to regulate somatostatin release.
Ejiri
K
K
Second Department of Internal Medicine, Kobe University School of Medicine, Japan.
Taniguchi
H
H
Baba
S
S
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D000906:Antibodies; D001285:Atropine / Q000494:pharmacology*; D002038:Bungarotoxins / Q000494:pharmacology; D005934:Glucagon / Q000378:metabolism*; D006801:Humans; D007074:Immunoglobulin G; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009157:Myasthenia Gravis / Q000276:immunology; D051381:Rats; D011919:Rats, Inbred Strains; D011978:Receptors, Nicotinic / Q000187:drug effects / Q000276:immunology / Q000502:physiology*; D012016:Reference Values; D013004:Somatostatin / Q000378:metabolism*
D000906:Antibodies; D002038:Bungarotoxins; D007074:Immunoglobulin G; D007328:Insulin; D011978:Receptors, Nicotinic; D013004:Somatostatin; D001285:Atropine; D005934:Glucagon; D000109:Acetylcholine