Intracellular potentials of visceronociceptive neurons in posterior group of thalamic nuclei and its labeling with HRP intracellularly in cat.

The intracellular potentials (ICP) of 42 visceronociceptive neurons related to stimulating greater splanchnic nerve (SPL) in Posterior group of thalamic nuclei (PO) were investigated. We analyzed the electrophysiological features, such as amplitude of resting potentials and action potentials of the neurons. Following acquisition of electrophysiological data, (HRP) was injected into 3 neurons, whose responses were inducted by stimulating SPL (related neurons) and able to be inhibited by morphine intravenously. Two neurons revealing spontaneous discharges but are not able to evoke response by stimulating SPL (non-related neurons), also were stained by HRP. Two kinds of neurons, related and non-related ones, display different dendrite branching patterns.