PARADOXICAL SYMPATHETIC-NERVE RESPONSE TO BARORECEPTOR REFLEX ACTIVATION

Spectral analysis revealed an enhancement of cardiac-related postgangl ionic sympathetic nerve discharge (SND) in response to elevated blood pressure in cats. Most of the enhancement occurred at blood-pressure l evels above which coherence of SND to the arterial pulse at the freque ncy of the heart beat became maximal. This raises the possibility that the enhancement is due to mechanisms other than improved phase lockin g of SND to pulse-synchronous baroreceptor afferent nerve activity. (C ) 1998 Elsevier Science B.V.