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Abstract: The effects of long-term cold exposure (10°C for 11weeks) and of deacclimation from cold (25°C for 2 weeks, after 10°C for 9 weeks) were investigated in obese and lean Zucker rats. Morphological change was observed in the liver during cold acclimation and deacclimation. Hepatic glycogen content decreased during cold adaptation, more markedly in obese rats. However, plasma glucose levels remained unchanged. After deacclimation, the glycogen content increased when compared to the original level, conspicuously in lean rats. Leptin receptor protein was decreased by cold acclimation in lean, but not obese, rats. Cold acclimation and deacclimation had no effect on expression of GLUT2 or PGC1 protein in either strain. [Copyright &y& Elsevier]

The effects of acoustic and visual stimuli and their synergistic effects on heart rate variability including gender differences were investigated. Of particular interest was the influence of visual stimulus on heart rate variability during listening to simple sounds of different characters. Twelve male and 12 female university students were selected as subjects. The subjects listened at rest to 7 different figures of sound at loudness levels averaging 60 dB. Beat-to-beat R-R intervals were continuously recorded under the closed-eye condition (CEC) and the open-eye condition (OEC) prior to, during, and immediately after the exposure to acoustic stimuli. Low frequency (LF) power was defined over 0.04-0.15 Hz and high frequency (HF) power over 0.15-0.40 Hz. Cardiac autonomic function was estimated by plotting LF/HF in standard measure against HF in standard measure and by plotting LF/HF (%) against HF (%), accompanied by a demarcated central area. Values of LF/HF tended to be smaller under CEC than under OEC. Values of HF while listening to a 110 Hz sine wave under CEC were significantly greater than values for 880 Hz and 3520 Hz sine waves, or for 110 Hz or 880 Hz sawtooth waves, under OEC. Under CEC, values of HF for 7 figures of sound were greater in females than in males. The value of HF of sine wave for 110 Hz under CEC and OEC was significantly greater than that for white noise under the OEC. The results suggest that the cardiac parasympathetic nervous activity during auditory excitation increases with elimination of visual stimuli and tends to be greater in females than in males.