Effects of an antiserum to rat growth hormone and bromocriptine on cholesterol-metabolizing enzymes in the lactating rat mammary gland
| Autor: | J. H. Shand, D. W. West |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
medicine.medical_specialty
Endocrinology Diabetes and Metabolism Sterol O-acyltransferase Biology Reductase chemistry.chemical_compound Mammary Glands Animal Endocrinology Pregnancy Microsomes Internal medicine medicine Animals Lactation Bromocriptine chemistry.chemical_classification Cholesterol Immune Sera Hydroxymethylglutaryl-CoA reductase Prolactin Rats Enzyme chemistry Growth Hormone Microsome Female Hydroxymethylglutaryl CoA Reductases Cholesterol Esters Sterol O-Acyltransferase medicine.drug |
| Zdroj: | Journal of Endocrinology. 128:287-295 |
| ISSN: | 1479-6805 0022-0795 |
| DOI: | 10.1677/joe.0.1280287 |
| Popis: | Rats in mid-lactation were treated, for 2 days, with anti-rat GH serum (anti-rGH) and/or bromocriptine before microsomes were prepared from the freeze-clamped mammary glands. The effects of these anti-hormone treatments on the concentrations of microsomal cholesterol and cholesterol esters and on the activities of acyl-CoA:cholesterol acyltransferase (ACAT), neutral cholesterol ester hydrolase and 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA reductase) were measured. HMG-CoA reductase was determined in microsomes prepared in both the presence and absence of phosphatase inhibitors to determine the expressed and total activities respectively. Anti-rGH reduced HMG-CoA reductase and increased microsomal cholesterol and cholesterol esters. Bromocriptine reduced HMG-CoA reductase but increased all of the other parameters. The results indicate that the initial stage in the stimulation of milk secretion involves a decrease in the activity of ACAT and that the phosphorylation level of HMG-CoA reductase is modulated by both prolactin and GH acting in opposition. Journal of Endocrinology (1991) 128, 287–295 |
| Databáze: | OpenAIRE |
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