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Biomedical subjects

E F Adolph

Publications and source records attributed to E F Adolph.

At least 19 recordsLinked to original sources
PubMed1984

Physiological regulations and compartments in cells.

Quantitative short-term regulation of a chemical component (glucose) in a single cell (hepatocyte of rat) is represented by an "equilibration diagram," which relates concentration of the regulated component or substrate (glucose) to loss and to gain of the same substrate (glucose). Loss and gain are separately active through specific enzymatic processes. Evidence indicates that some of these processes require the presence of subcellular compartments for their participation.

Adenosine Triphosphate↗
PubMed1983

Uptakes and uses of oxygen, from gametes to maturity: an overview.

How do rates of oxygen uptakes per unit of body weight change with age in mammals? Marked increases occur, starting on the third day after fertilization; small increases occur just after birth. At birth the factor of body size of the species has a small influence. In the old adult the diminished uptake per unit weight resembles that of the newly fertilized zygote. Special roles of RNA and of mitochondria determine the uses to which energy is put. Anaerobic energy is and can be employed temporarily in embryonic stages. Sensitivities to energy demands are revealed in effects of hypoxia, hyperoxia, low temperatures and norepinephrine. Uses of energy for biosyntheses and active transports change during ontogeny; and differ among the tissues. Strategies of development, and their sequences, appear to supply adequate oxygen throughout prenatal stages.

Aging↗
PubMed1982

Termination of drinking: satiation.

Speeds of swallowing water differ among species, for example, in the dog and rat. Alimentary factors predominate in the termination of drinking. Parenteral water avoids alimentary factors, yet can also lead to delayed satiation. Central factors of termination are also recognized, especially in the neurohypophysis. Kinetics of various intakes (food, sodium, oxygen, heat) show analogous patterns of satiation or saturation. Such intakes have in common the dimensions of clearances of deficits.

Animals↗
PubMed1981

Regulations of intakes: clearances.

1) Intakes of substances (oxygen, food) are related to availability or concentration of the substance that is being taken from the environment. This removal accords with dimensions of clearance. 2) Intakes from limited sources, as gut or pocket, also vary with the concentrations there. 3) Reabsorptions of selected substances during excretion are intakes into body. 4) Intakes respond to bodily deficits of materials (water, sodium, heat). Wherever plasma or other concentrations are measured, intake clearances may be computed. These four relations allow quantitative comparisons of the mechanisms and regulations for transport of various substances into body or cells. Kinetic "constants" can be estimated.

Absorption↗
PubMed1979

Development of dependence on oxygen in embryo salamanders.

Survival times in anoxia and hypoxia were measured at various stages of development in Ambystoma embryos and larvae of two species. Survival times in anoxia at 20 degrees C shifted from more than 30 h at 2 days after fertilization to 20 h at 10 days of age, to only 4--2 h at 14 days of age. In hypoxia (oxygen pressure equivalent to 3.8% oxygen) similar shifts of survival times appeared about 7 days of age later. During anoxia heart rates decreased, less at younger stages than at older. At older stages the heart stopped beating, sometimes irreversibly. In hypoxia also, hearts at all stages whether in situ or isolated decreased their rates of beat. Oxygen uptakes of larvae diminished in oxygen pressures even as high as 11% oxygen. This critical oxygen pressure did not change between early stages without blood flow and later stages with blood flow. Oxygen uptake was probably not limited by oxygen delivery but presumably by properties of cellular masses. No oxygen debts were paid off. Some parallel changes of tolerances to anoxia in embryo birds and mammals are noted.

Animals↗
PubMed1979

Look at physiological integration.

Physiological integration results from cooperating processes at work within an individual. Two chief types of study are a) empirical experiments and generalizations, and b) predictive relations derived from models. In this essay the empirical type is illustrated. For example, heart rates and other circulatory properties are modified in response to messages from specific muscles, viscera, glands. In those tissues, augmented blood flow increases the supplies of oxygen and other substances at active local sites. Because specialized actions are segregated among tissues and organs, each performer evidently informs cooperating tissues of its state. Messages are transmitted at various kinds of junctions and chemical receptors. In this essay the results or actions are emphasized: in what ways do the compounded processes promote survival and advantage? Messages are sorted as they travel, certain powers of decision residing at cellular junctions. Because selected processes are corrdinated, each compound action represents an accomplishment. Thermoregulation serves as an example of relations by which several parameters yield a complex result. The multiple correlations and the intricate timing and switching are recognized.

Animals↗
PubMed1976

O2 extraction of right and left ventricles.

O2 extraction was measured simultaneously in right and left ventricles of dogs. Extraction was about 2.5 vol% higher in left ventricle. This figure, together with flow measurements of others (1-3), indicates that VO2/100g is at least twice as great in left ventricle as in right.

Animals↗