caa a22 4500 465804152 CHVBK 20180323112059.0 cr unu---uuuuu 170327e19901001xx s 000 0 eng 10.1007/BF03349617 doi (NATIONALLICENCE)springer-10.1007/BF03349617 Increase by naloxone of arginine vasopressin and oxytocin responses to insulin-induced hypoglycemia in obese men [Elektronische Daten] [Vittorio Coiro, L. Capretti, G. Speroni, A. Castelli, L. Bianconi, U. Cavazzini, A. Marcato, R. Volpi, P. Chiodera] The present study was carried out to establish whether the low arginine vasopressin (AVP) and oxytocin (OT) responses to insulin-induced hypoglycemia observed in obese men was due to alteration of the opioid control of posterior pituitary function. For this purpose, the AVP and OT releasing effect of insulin (0.15 lU/kg bw) — induced hypoglycemia was tested in eight normal weight men and in 10 age-matched obese subjects, without and with the previous treatment with the specific opioid receptor antagonist naloxone (3 mg in an iv bolus). In a control study, naloxone was given alone to the same subjects. Obese men showed similar basal glucose, AVP and OT levels, which remained unmodified after treatment with naloxone alone. Insulin induced a similar decrement of blood glucose levels in all subjects, with a nadir at 30 min. Plasma levels of AVP and OT rose strikingly in normal and obese subjects with mean peak responses at 30 min for AVP and at 45 min for OT. However, both AVP and OT responses were significantly lower in obese than in control subjects. Pretreatment with naloxone did not modify the AVP and OT responses to hypoglycemia in normal weight subjects, whereas it significantly enhanced both hormonal responses in obese subjects. In the presence of naloxone normal controls and obese subjects showed similar responses of both AVP and OT to hypoglycemia. These data indicate that an abnormal activity of endogenous opioids might account for the hypothalamic posterior pituitary dysfunction, which is responsible for the low AVP and OT responses to insulin-induced hypoglycemia in obesity. Italian Society of Endocrinology (SIE), 1990 Arginine vasopressin nationallicence oxytocin nationallicence naloxone nationallicence hypoglycemia nationallicence obesity nationallicence Coiro Vittorio Cattedra di Clinica Medica Generale e Terapia Medica, University of Parma, via Gramsci 14, 43100, Parma, Italy aut Capretti L. Divisione di Medicina Interna, Ospedale di Codogno, 20073, Codogno, MI, Italy aut Speroni G. Divisione di Medicina Interna, Ospedale di Codogno, 20073, Codogno, MI, Italy aut Castelli A. Divisione di Medicina Interna, Ospedale di Piacenza, 29100, Piacenza, Italy aut Bianconi L. Cattedra di Endocrinologia e Patologia Costituzionale, University of Parma, 43100, Parma, Italy aut Cavazzini U. Cattedra di Clinica Medica Generale e Terapia Medica, University of Parma, via Gramsci 14, 43100, Parma, Italy aut Marcato A. Cattedra di Clinica Medica Generale e Terapia Medica, University of Parma, via Gramsci 14, 43100, Parma, Italy aut Volpi R. Cattedra di Clinica Medica Generale e Terapia Medica, University of Parma, via Gramsci 14, 43100, Parma, Italy aut Chiodera P. Cattedra di Endocrinologia e Patologia Costituzionale, University of Parma, 43100, Parma, Italy aut Journal of Endocrinological Investigation Springer International Publishing 13/9(1990-10-01), 757-763 0391-4097 13:9<757 1990 13 40618 https://doi.org/10.1007/BF03349617 text/html Onlinezugriff via DOI 1 brief-communication jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF03349617 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Coiro Vittorio Cattedra di Clinica Medica Generale e Terapia Medica, University of Parma, via Gramsci 14, 43100, Parma, Italy aut NATIONALLICENCE 700 1- Capretti L. Divisione di Medicina Interna, Ospedale di Codogno, 20073, Codogno, MI, Italy aut NATIONALLICENCE 700 1- Speroni G. Divisione di Medicina Interna, Ospedale di Codogno, 20073, Codogno, MI, Italy aut NATIONALLICENCE 700 1- Castelli A. Divisione di Medicina Interna, Ospedale di Piacenza, 29100, Piacenza, Italy aut NATIONALLICENCE 700 1- Bianconi L. Cattedra di Endocrinologia e Patologia Costituzionale, University of Parma, 43100, Parma, Italy aut NATIONALLICENCE 700 1- Cavazzini U. Cattedra di Clinica Medica Generale e Terapia Medica, University of Parma, via Gramsci 14, 43100, Parma, Italy aut NATIONALLICENCE 700 1- Marcato A. Cattedra di Clinica Medica Generale e Terapia Medica, University of Parma, via Gramsci 14, 43100, Parma, Italy aut NATIONALLICENCE 700 1- Volpi R. Cattedra di Clinica Medica Generale e Terapia Medica, University of Parma, via Gramsci 14, 43100, Parma, Italy aut NATIONALLICENCE 700 1- Chiodera P. Cattedra di Endocrinologia e Patologia Costituzionale, University of Parma, 43100, Parma, Italy aut NATIONALLICENCE 773 0- Journal of Endocrinological Investigation Springer International Publishing 13/9(1990-10-01), 757-763 0391-4097 13:9<757 1990 13 40618 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer