Tetsuo Nagasaka

Learn More
The effect of running on heat production in brown adipose tissue (BAT) was compared between trained and untrained rats. Rats were forced to run a treadmill while temperatures of colon (T col) and interscapular BAT (T bat) were measured. The daily running for 5 weeks neither changed the size of interscapular BAT nor the norepinephrine-induced thermogenesis(More)
Local concentrations of the vasopressor peptide, angiotensin II (AngII), depend upon the balance between synthesis and degradation. Previous studies of blood pressure (BP) regulation have focused primarily on the generation of AngII and its receptors, and less attention has been devoted to angiotensin degradation. Aminopeptidase A (APA, EC is(More)
The effect of a single cortical spreading depression (CSD), elicited unilaterally by 10% KCI injection at the occipital cortex, was observed on the metabolic heat production in the rat with unilateral lesions in the preoptic and anterior hypothalamus (PO/AH). The metabolic rate increased by maximally 20% above its pre-CSD level for 7 min with a rise in(More)
The role of the ventromedial hypothalamic nucleus (VMH) in the generation of the prefeeding corticosterone peak was examined in rats under restricted daily feeding, under which daily meal supply was restricted to a fixed time in the early light period. Rats were lesioned in the VMH bilaterally and subjected to restricted daily feeding during two different(More)
1. Heat-acclimated (HA) rats, kept under a 12:12 h light-dark regime, were subjected to an ambient temperature (Ta) of 33 degrees C for 5 h in the last half of the dark phase for 3 weeks. Control rats were kept under a 12:12 h light-dark regime at a constant Ta of 24 degrees C. 2. After the acclimation period, the rats were then placed in a metabolic(More)
Male Wistar rats were acclimated to cages with running wheels. Then, the running time of rats were limited to the last 3 (WR3) or 6 (WR6) h of the dark phase. After a 2-week activity restriction, the rats were again allowed access to the wheel freely. In the WR3 or WR6, wheel revolutions for the last 3 or 6 h of the dark phase was significantly greater(More)
This study investigated the day-night differences in behavioral and autonomic thermoregulatory responses to bacterial lipopolysaccharide (LPS) in rats. Male rats were housed individually in cages with a 12: 12 h light dark cycle at an ambient temperature of 24 degrees C. The rats were placed in a box with a temperature gradient and intraperitoneally(More)
Male Wistar rats were divided into two groups. The controls (CN) were kept at a constant ambient temperature (Ta) of 24 degrees C throughout the experiment. Heat-acclimated rats (HA) were subjected to Ta of 33 degrees C in the last half of the dark phase for 16 consecutive days. After the schedule was terminated, hypothalamic temperature (Thy), oxygen(More)
Several timed daily environmental cues alter the pattern of nycthemeral variations in body core temperature in rodents. The present study investigated the effect of timed exercise on variations of daily body core temperature. Male rats were housed in cages with a running wheel at an ambient temperature of 24 degrees C with a 12:12 h light/dark cycle. Timed(More)
Finger blood flow (BF) and skin sympathetic nerve activity (SSA) to the glabrous side of the hand were measured during immersion of the hand in a water bath in which temperature (Tw) was raised every 10 min by steps of 2 degrees C from 35 or 37 to 41 degrees C. The experiments were conducted during the summer in rooms in which ambient temperature was 28-32(More)