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Biomedical subjects

S Patton

Publications and source records attributed to S Patton.

At least 127 records · Page 7Linked to original sources
PubMed1976

Adenosine triphosphate in milk.

Freshly secreted goat's milk contains a number of viable metabolic pathways including those for the synthesis of triglycerides and phospholipids. Toward understanding this matter, amounts of the fundamentally important energy substrate, adenosine triphosphate, in goat's milk were evaluated. Milk left in the goat udder overnight had less adenosine triphosphate (12.4 muM) than fresh secreted milk (37.6 muM). In similar experiments the skim milk derived from whole accumulating in the udder overnight was lower in adenosine triphosphate (14.2 muM) than skim milk from freshly secreted milk (26.0 muM). To determine changes in quantities of adenosine triphosphate after milking, milks were divided into two parts, one containing only milk and the other milk plus 2,4-dinitrophenol and sodium arsenate, inhibitors of oxidative and substrate level phosphorylation. Adenosine triphosphate in milk decreased during 4-h in vitro incubations, and the rate of decline was markedly greater in the presence of the inhibitors. Thus, freshly secreted goat's milk contains significant amounts of adenosine triphosphate, and more can be synthesized therein after removal from the udder. In limited samples human and bovine milks contained much lower concentrations of the compound than those in goat's milk.

Adenosine Diphosphate↗
PubMed1976

Mechanisms of secretion: effects of colchicine and vincristine on composition and flow of milk in the goat.

Colchicine, the plant alkaloid, produced a dramatic decrease in milk flow when infused into the udder of the goat. The compound (1 to 5 mg) dissolved in 5 ml of water was inserted into one side of the under via the teat canal. Such treatments consistently caused a depression in milk yield from the infused side with maximum at 36 h and substantial reversal by 72 to 96 h. Milks from both the infused and uninfused sides of the udder were essentially normal in composition (fat, protein, and lactose). However, globulins and riboflavin were elevated in milks from the infused side. The plant alkaloid, vincristine, produced effects on milk secretion similar to those of colchicine but at dosages roughly one-tenth the latter. The two substances had no effect on the amount of milk from the uninfused side of the udder. Experiments employing [carbon-14] colchicine revealed that less than 20% of the infused colchicine is secreted in the milk. Both the secretion of fat globules and the emptying of secretory vesicles by the lactating cell are inhibited by colchicine indicating that a portion of the cell population is turned off from secretion. Plant substances such as colchicine and vincristine may at times limit yields of milk, especially in grazing ruminants.

Animals↗
PubMed1975

Transport of dietary cholesterol into blood and milk of the goat.

Position 4 labeled carbon-14 cholesterol was placed in abomasums (stomachs) of two lactating goats. Blood and milk samples were collected from the animals for 5 to 13 days. Specific activities of cholesterol and cholesteryl esters in various fractions of blood serum and milk were determined to reveal pathways by which dietary cholesterol enters milk. Results with the two animals showed similar trends. Within 24 h both cholesterol and cholesteryl esters of the three principal serum lipoproteins of the goat were labeled, and this labeling persisted in substantial degree for the 13-day experiment. Specific acities for cholesteryl esters in milk fat globules exhibited several remarkable attributes: they fluctuated in intensity with a 3-to 4-day cycle reaching a maximum at 7 to 8 days after tracer injection; they exceeded cholesteryl ester specific activity in the skim milk by an order of magnitude; and at their maximum they exceeded all specific activities for serum components. The results of this investigation exemplify the ease with which dietary cholesterol enters and crosses membranes in the animal body.

Animals↗