Characterization of the very late cardiosympathetic A-reflex in high-mesencephalic cats.

In unanaesthetized mid-collicular decerebrate cats, stimulation of low-threshold afferents running in the inferior cardiac nerve can evoke in renal nerve a long-latency reflex response, which is able to reduce or overcome the inhibition developing after the late response. The spatial and temporal summation have great importance in generating this very late response (VLR). Increasing the stimulus intensity and the frequency of the impulses, using short trains or a previous A + C tetanic stimulation of the segmental inputs considerably increased the chance of the VLR overcoming the late inhibition.

[Noradrenaline suppression of the spinal efferent component of the pressor reflexes].

Noradrenaline applied to the dorsal surface of spinal cord segments C6-T1 suppressed the pressor components of the blood pressure reflexes evoked by stimulation of radial nerve afferents in anesthetized cats. Noradrenaline applied to spinal cord segments L4-S1 suppressed pressor reflexes elicited by stimulation of tibial nerve afferents. The increase in noradrenaline concentration from 0.