Different effects of the serotonergic agonists buspirone and sumatriptan on the posterior pituitary hormonal responses to hypoglycemia in humans.
The responses of serum oxytocin (OT) and vasopressin (AVP) to the serotonergic HT1A agonist buspirone (15 mg p.o.) or the HTD1 agonist sumatriptan (6 mg injected subcutaneously) were evaluated in 7 normal men either in basal conditions or during an insulin (0.15 iu/kg as an i.v. bolus) tolerance test (ITT). Neither buspirone nor sumatriptan administration modified the basal secretion of AVP and OT. Stimulation of 5HT-1D receptors with sumatriptan was unable to change neither AVP nor OT response to insulin-induced hypoglycemia. On the other hand, the pretreatment with the 5HT1A agonist buspirone significantly enhanced the OT response during hypoglycemia, without modifying the AVP rise. The results of this study suggest that serotonergic 5HT1A receptors may interact with hypoglycemia in the stimulation of OT, but not AVP secretion.
Chiodera
P
P
Cattedra di Endocrinologia, Università di Parma, Italy.
Volpi
R
R
Capretti
L
L
Caffarri
G
G
Magotti
M G
MG
Coiro
V
V
D000328:Adult; D001127:Arginine Vasopressin / Q000097:blood; D002065:Buspirone / Q000494:pharmacology*; D006801:Humans; D007003:Hypoglycemia / Q000097:blood*; D007328:Insulin; D008297:Male; D010121:Oxytocin / Q000097:blood; D010909:Pituitary Hormones, Posterior / Q000097:blood*; D011985:Receptors, Serotonin / Q000187:drug effects / Q000502:physiology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*; D018170:Sumatriptan / Q000494:pharmacology*
D007328:Insulin; D010909:Pituitary Hormones, Posterior; D011985:Receptors, Serotonin; D017366:Serotonin Receptor Agonists; D001127:Arginine Vasopressin; D010121:Oxytocin; D018170:Sumatriptan; D002065:Buspirone