Circahoralian rhythms in assessment of heart rate variability.

Circahoralian oscillations of various indices describing variations of interpulse, respiratory, and R-R intervals were recorded in normal subjects, in hypertensive patients, and in patients rehabilitating after cardiac infarction. The parameters of these rhythms reflect changes in the status of autonomic nervous system, correlate with pathological disturbances in circadian rhythm, and accompany the sleep-wake and wake-sleep transitions. In assessment of circadian rhythm parameters, the most informative are the plots of changes in Pierson correlation coefficients of interpulse and R-R intervals.

[Endocellular regulation of oxygen consumption in the neurone of isolated crawfish stretch receptor].

Morphological correlations of functional regulation of oxygen consumption have been investigated in single of isolated crustacean stretch receptor neuron. The increase in oxygen consumption is promoted by: 1) redistribution of mitochondria and increase in cytochrome oxidase (CO) activity in mitochondria near to the plasmatic membrane; 2) coordination of mitochondria aggregation rhythms with pO2 rhythms in external environment of a cell; 3) reduction of the area with high CO and mitochondria activity, and reduction of the way of oxygen diffusion; 4) increase in CO activity gradient from periphery to the center of the neuron body; 5) carry of oxygen by water current under hydration of the neuron body, and cytoplasm dilution under transition of a part of gel in sol; 6) cyclic changes in the neuron body and hillock sizes ratio determining carry of oxygen by water current into the neuron body, oxygen absorption by mitochondria in the neuron body, and transition of the water released from oxygen from the neuron body into hillock and further into the external environment.