Fig. 14.

Blood flow (electromagnetic flow probe measurement) to hindfoot (A. dors. ped.) in a catecholamine-depleted (reserpinized) anesthetized dog. Blood flow is distinctly increased by spinal cord warming, using a water-perfused thermode located in the peridural space. Water temperature at entrance of thermode (T _p, white bars). Absence of effective vasoconstrictor innervation is indicated by the vasodilator response to electro-stimulation (St) of the ipsilateral lumbar sympathetic chain. As expected, phenoxybenzamine (Phen) as a blocker of alpha-adrenergic transmission prevailing in skin blood vessel vasoconstrictor innervation is ineffective and leaves thermally induced blood flow increase unimpaired. Enhanced blood flow during spinal cord warming is abolished by transection (Tr) of the ipsilateral lumbar sympathetic chain. Arterial pressure (Pm _ar) does not change. From Schönung et al. [70]