Most of the transcranial Doppler (TCD) experimental studies on
cerebral haemodynamics have been performed in the rabbit
because of the similarity between its Willis circle and that of the
human, but these studies have mainly been limited to the basilar
artery. The present study was aimed at extending the use of TCD
sonography to all other large cerebral arteries. In anaesthetised
rabbits, these arteries were insonated from three different recording sites, i.e.
top-cranial, suboccipital and orbital, using a two-channel pulsed Doppler device
equipped with 4 and 8 MHz probes. First, discrimination between intra- and
extracranial arteries was achieved through a standard 'rebreathing' test
(hypercapnic-hypoxic stimulation). The distinctive blood velocity response
patterns, reflecting the different extents of metabolic reactivity in intra- and
extracranial territories, are described and discussed. Intracranial arteries were
then identified on the basis of their response to ipsi- and contralateral common
carotid artery occlusion. This procedure allowed recording from the following
arteries: anterior common trunk, anterior cerebral, internal carotid, middle
cerebral and basilar; the latter could be simultaneously monitored with any of
the others. This study provides an experimental model allowing investigation of
regional differences in the haemodynamic response to neurogenic and
pharmacological stimuli.