Demonstration of a dawn phenomenon in normal human volunteers.
Diabetes
; 33(12): 1150-3, 1984 Dec.
Article
em En
| MEDLINE
| ID: mdl-6389230
ABSTRACT
To ascertain whether the dawn phenomenon occurs in nondiabetic individuals and, if so, whether it is due to an increase in glucose production or a decrease in glucose utilization, we determined plasma concentrations of glucose, insulin, C-peptide, and counterregulatory hormones, as well as rates of glucose production, glucose utilization, and insulin secretion at one-half-hourly intervals between 100 and 900 a.m. in eight normal volunteers. After 530 a.m., plasma glucose, insulin, and C-peptide concentrations all increased significantly; rates of glucose production, glucose utilization, and insulin secretion also increased (all P less than 0.05). Plasma cortisol, epinephrine, and norepinephrine increased significantly from nocturnal nadirs between 400 and 630 a.m. Plasma growth hormone, which had increased episodically between 100 and 430 a.m., decreased thereafter nearly 50% (P less than 0.05). Plasma glucagon did not change significantly throughout the period of observation. These results indicate that a dawn-like phenomenon, initiated by an increase in glucose production, occurs in nondiabetic individuals. Thus, early morning increases in plasma glucose concentrations and insulin requirements observed in IDDM and NIDDM may be an exaggeration of a physiologic circadian variation in hepatic insulin sensitivity induced by antecedent changes in catecholamine and/or growth hormone secretion.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Glicemia
/
Ritmo Circadiano
/
Homeostase
Limite:
Adult
/
Humans
/
Male
Idioma:
En
Ano de publicação:
1984
Tipo de documento:
Article