Influences of weight reduction on the circadian rhythm of cardiac parasympathetic activity in obesity

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CIRCADIAN-CONTROLLED ACTIVATION OF TRANSCRIPTION IN PAT SUPRACHIASMATIC NUCLEUS. -0. MAREK RANASIK AND NORIO ISa I Cell BioL Ib&i.

305.

JaDa

The Suprachiasmatic nuclei (SCN) are the principal site of the lightentrainable circadian pacemaker in mammals. We have already reported that the mRNA expression of NMDARl gene is fluctuated by the circadian clock in the SCN. In order to approach the transcriptional regulation of this gene, we analyzed the binding activities of several transcription factors to the promotor region of NMDARl. Our results suggest that CREB (CAMP-responsible element binding protein) binding activity underlies the circadian expression of NMDARl mRNA.

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SPECTRAL SENSITIVITY OF PHOTORECEPTOR(S) MEDIATING ENTRAINMENT OF CIRCADIAN RHYTHMS IN MICE. TAKASHI YOSHIMURA AND SHIZUFUMI EBIHARA ,Department of Animal Phvsiologv,

School of Aqricultural Science, Nasova Universitv, Chikusa, Naqova, 464-01, Japan We have shown that retinally degenerate CBA/J (rd/rd) mice have lower circadian photosensitivity than normal CBA/N (+/+) mice. In order to clarify the cause for the difference, we have examined the spectral sensitivities of photoreceptor(s) mediating entrainment of circadian wheel-running rhythms in these strains. The results show that the spectral sensitivity curve of CBA/J mice resemble to that of retinal1 based photopigment which has a peak at 480nm, while that of CBA/N mice differ from that of retinal1 based photopigment.

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INFLUMCES

OF

PARASYMFATHHTIC

WEIGHT

REUUCTION

ACTIVITY

ON

IN OBESITY.

THE

CIRCADIAN

RHYTHM

YUKO AKEHI. MAMORU

OF

CARDIAC

KUROKAWA. HIRONOBU

YOSHIMATSU AND TOSHIIE SAKATA. Dept. of Internal Medicine I, School of Medicine, Oita Medical Univ..Oita. Japan To clarify the functional impairment of autonomic nervous system in the development of obesity, changes in autonomic function assessed by a spectral analysis of heart rate variability were investigated in obese subjects before and after slimming treatment. Accompanying the weight reduction (14.3%6.9kg), indicators of tonic parasympathetic activity by Holter ECG significantly increased and indicator of sympathetic function activity showed significant Change of indicator of parasympathetic decreased. correlation with reduction weight. Circadian variation of cardioautonomic parameters predominantly changed during night time. These indicate that imbalance of autonomic nervous system and its distorted rhythmicity is involved in the pathogenesis of obesity.