Sucrose feeding effects inhibition of γ-glutamyltranspeptidase in the liver of the rat: possible mediation by thyroid hormone
| Autor: | Satchan Takaya, Susan J. Hemmings |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Blood Glucose
Male Sucrose Thyroid Hormones medicine.medical_specialty Rodent medicine.medical_treatment Radioimmunoassay Biology Biochemistry chemistry.chemical_compound Sex Factors Pregnancy Internal medicine biology.animal medicine Animals Insulin Kidney γ glutamyltranspeptidase Cell Membrane Thyroid Age Factors gamma-Glutamyltransferase Cell Biology Rats Inbred F344 Diet Rats medicine.anatomical_structure Endocrinology Animals Newborn Liver chemistry Gestation Female Hormone |
| Zdroj: | The International Journal of Biochemistry & Cell Biology. 35:51-60 |
| ISSN: | 1357-2725 |
| DOI: | 10.1016/s1357-2725(02)00088-2 |
| Popis: | The effect of sucrose on Fischer 344 rat liver gamma-glutamyltranspeptidase (gammaGT) was studied: in adults fed sucrose for 3 weeks; and rats exposed to sucrose from the 18th day of gestation to the 40th day after birth. Rats fed regular rodent chow served as controls. Sucrose caused mild lipemia; and in the liver an increase in size and fat build-up without damage. In adult sucrose-fed rats, compared to controls, plasma glucose levels were increased: 1.12-, 1.40- and 1.13-fold after 24, 48h and 3 week consumption of sucrose, respectively. Insulin levels were unaltered for the first week of sucrose consumption but increased from control levels: 16% at 1 week, and 2.0-fold at 3 weeks. The T3 levels were comparable to control levels 24h after the sucrose was started and were increased: 1.22-, 1.13- and 1.12-fold at 48h, 1 and 3 weeks, respectively. The T4 levels were comparable at all time points between sucrose-fed and control rats. Liver gammaGT activity exhibited a steady decrease from control levels: after 24, 48h, 1 and 3 weeks of sucrose feeding the decrease was 5, 8, 21 and 37%, respectively in homogenates; and 10, 17, 24 and 41%, respectively in plasma membranes. Perinatal sucrose exposure effected in 40-day-old rats, compared controls: a 1.09-fold increase in plasma glucose; no change in plasma insulin; an increase of 1.15- and 1.39-fold in plasma levels of total and free T3, respectively; a decrease of 20 and 14% in plasma levels of total and free T4, respectively. gammaGT activity was decreased in liver plasma membranes isolated from sucrose-exposed rats relative to those of control: 80% in the male; 82% in the female. Relative specific activities of gammaGT were the same in both males: 15.4 and 16.1 in control and sucrose-exposed male rats, respectively; and females: 14.1 and 15.4 in control and sucrose-exposed female rats, respectively. gammaGT was 2-fold higher in the livers of female relative to male rats in sucrose-exposed and control groups. Kidney gammaGT activities were the same in control and sucrose-exposed rats. The involvement of T3 in the sucrose-induced decrease in liver gammaGT is discussed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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