Serotonin-induced hypoglycemia and increased serum insulin levels in mice.
The effects of serotonin (5-HT) on plasma glucose levels were studied. 5-HT above 20 mg/kg induced apparent hypoglycemia in mice. The hypoglycemic effects of 5-HT were strongly antagonized by methysergide but only partially inhibited by ketanserin. However, ICS 205-930 was without effect. This indicates that the hypoglycemia induced by 5-HT is mediated by both the 5-HT1 and 5-HT2 receptors. 5-HT also produced an increase in serum immunoreactive insulin (IRI) which was completely inhibited by methysergide and partially antagonized by ketanserin. It is suggested that the 5-HT-induced increase in IRI is elicited by the activation of the 5-HT1 and 5-HT2 receptors, which is similar to the results obtained with plasma glucose. These results indicate that the 5-HT receptors may regulate blood glucose levels by modifying the release of insulin.
Yamada
J
J
Department of Pharmacology, Kobe Women's College of Pharmacy, Japan.
Sugimoto
Y
Y
Kimura
I
I
Takeuchi
N
N
Horisaka
K
K
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D007003:Hypoglycemia / Q000139:chemically induced*; D007211:Indoles / Q000494:pharmacology; D007328:Insulin / Q000097:blood*; D007650:Ketanserin / Q000494:pharmacology; D008297:Male; D008784:Methysergide / Q000494:pharmacology; D051379:Mice; D011985:Receptors, Serotonin / Q000502:physiology; D012701:Serotonin / Q000494:pharmacology*; D012702:Serotonin Antagonists / Q000494:pharmacology; D000077526:Tropisetron
D001786:Blood Glucose; D007211:Indoles; D007328:Insulin; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D012701:Serotonin; D000077526:Tropisetron; D007650:Ketanserin; D008784:Methysergide