抄録
To understand the integrative roles of the paraventricular nucleus (PVN) in the central regulation of autonomic and endocrine systems, we simultaneously recorded the single unit in the PVN, arterial blood pressure, electrocardiogram (ECG), electroencepharogram (EEG) and electromyogram (EMG) of cervical muscle in conscious freely-moving rats. The miniature drivable apparatus with eight microwires was implanted to the skull for the recording of single unit. Three groups of neurons were revealed by the cross-correlation analysis between heart rate (HR) and firing rate of unit activity. Group 1 neurons showed a positive correlation. The firing rate started to increase 2-4 sec prior to increasing HR. Group 2 neurons showed a negative correlation at similar lag. Group 3 did not show a consistent relationship between HR and firing rate. Some of this type showed rhythmic phasic activity pattern. All groups did not showed a reflex changing in firing associated with perfusion of vasoactive drugs. However group 1 and 2 neurons increased and decrease in firing rate, respectively, in response to the moderate stressor. Sleep-wakefulness states were discriminated based on EEG and EMG. The simultaneous firing of neuron pairs not only across groups but also within group was subjected to additional cross-correlation analysis. The relationship was also compared between sleep-wakefulness states. These findings suggested that the combination of neurons in the PVN contribute to reciprocal control of autonomic nervous system. [J Physiol Sci. 2007;57 Suppl:S237]
