PubMed Health⌕ Search

Biomedical subjects

Rei Kobayashi

Publications and source records attributed to Rei Kobayashi.

3 recordsLinked to original sources

Altered venous capacitance as a cause of postprandial hypotension in multiple system atrophy.

Patients with multiple system atrophy (MSA) often have clinically significant postprandial hypotension (PPH). To elucidate the cause of insufficient cardiac preload augmentation that underlies PPH, we recorded calf venous capacitance (CVC) by strain-gauge plethysmography, in 17 MSA patients and eight healthy controls before and after oral glucose ingestion. Among 17 MSA patients, nine who showed a decrease in systolic blood pressure exceeding 20 mmHg and were diagnosed with PPH. MSA patients without PPH showed a significant decrease in CVC and a significant increase in cardiac output after oral glucose ingestion, as did controls; those with MSA exhibiting PPH showed a significant increase in CVC and no significant change in cardiac output. The change in CVC correlated positively with the decrease in systolic and diastolic blood pressure after glucose ingestion, and also correlated negatively with the increase in cardiac output. Physiologically, PPH is prevented by a decrease in venous capacitance, which increases circulating blood volume and cardiac output. In some MSA patients, failure of venous capacitance to decrease may induce PPH.

Aged↗

Skin sympathetic nerve function during sleep--a study with effector responses.

We investigated the effector-organ activities corresponding to skin sympathetic nerve activity (SSNA) during sleep in eight healthy adult volunteers. The following parameters of SSNA were recorded during night sleep: the spontaneous skin vasoconstriction and skin blood flow volume, by laser Doppler flowmetry; sweating, by the ventilated capsule method; and the galvanic skin response (GSR). Fluctuations of sweating and GSR were mainly observed on the dorsal side of the hand during night sleep. The frequency of GSR and sweat rate on the dorsal side of the hand were significantly lower during REM sleep than during NREM sleep. The frequency of spontaneous skin vasoconstriction was higher and blood flow was lower during REM sleep than during NREM sleep. These results indicate that sweating and blood flow in the skin are differentially regulated depending on the sleep stage. Our results also suggest that the sleep-regulating system is closely linked to thermoregulation, which is controlled by the sympathetic nervous system.

Adult↗