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S Tsuzuki T Fushiki A Kondo H Murayama E Sugimoto 《European journal of biochemistry》1991,199(1):245-252
The adaptation to a high protein diet of the concentration and mRNA level of a trypsin-sensitive, cholecystokinin-releasing peptide (monitor peptide), which was proposed to be the mediator of the cholecystokinin release in response to protein intake, was investigated in the rat pancreas. Adult rats were placed on one of two isocaloric diets. One group was fed a 22% casein diet (control diet) and the other a 64% casein diet (high-protein diet) for 14 days. In order to quantify the monitor peptide separately from pancreatic secretory trypsin inhibitor (PSTI-II), which is highly similar in its amino acid and mRNA nucleotide sequences to the monitor peptide but has less cholecystokinin-releasing activity, we used specific assay methods: HPLC was used for determining the monitor peptide concentration in zymogen granules and a synthetic oligonucleotide probe for determining the mRNA of the monitor peptide in the pancreas. The concentrations in the zymogen granules and the mRNA levels in the pancreas of the two peptides increased in parallel during the adaptation to the high protein diet, indicating that these two peptides were under the same control during the adaptation. The concentration and mRNA level of the monitor peptide, which were measured after 0, 3, and 14 days, increased throughout the experiment period, as did the concentration of trypsin. This suggested that the monitor peptide and trypsin may respond to similar signals during the adaptation to a high protein diet and that this apparent coordination may facilitate the adaptation of the pancreas to the diet. 相似文献
987.
S I Kusen' L I Sologub I E Sukhorskaia I S Pashkovskaia Ia T Sen'kus' 《Ukrainski? biokhimicheski? zhurnal》1989,61(1):79-81
It is established that insulin enhances the ability of the loach liver plasma membranes to phosphorylate lactate dehydrogenase. In the case of insulin-treated plasma membranes the amount of incorporated 32P is more than 4 times higher than that of the basal level. It is concluded that insulin-stimulated plasma membrane-dependent phosphorylation of the enzyme is one of the possible molecular mechanisms of hormone action on intracellular metabolism. 相似文献
988.
A B Maslennikov S P Kovalenko E A Oteva T A Filimonova N P Mertvetsov 《Genetika》1991,27(12):2152-2156
Restriction fragments' length polymorphism in the region of apolipoprotein A-I (apo A-I) gene was investigated in Novosibirsk (Siberia, USSR) population. Correlation between PstI apo A-I alleles (2,2 kb-P1; 3,3 kb-P2) and total cholesterol, triglycerides, high density polyproteins cholesterol, and apolipoprotein A-I level was analysed. A tendency to increase in cholesterol index of atherogenicity and to decrease in high density lipoproteins cholesterol as well as apolipoprotein A-I level was shown to occur for P1P2 genotype patients. 相似文献
989.
Sixteen raptors, including one eagle, two falcons, five hawks and eight owls, were found to have developmental ocular lesions. The most common lesion was microphthalmia. Other findings included cataract, microphakia, retinal dysplasia, malformation of the ciliary body, choroid and pecten, and lentoid formation. Specific causes for these lesions could not be determined. It is hypothesized that developmental ocular disease probably is more common than available reports indicate. 相似文献
990.