Electrophysiological responses of sympathetic preganglionic neurons to ANG II and aldosterone

iol 297: R699 –R706, 2009. First published June 24, 2009; doi:10.1152/ajpregu.00041.2009.—The intermediolateral cell col-umn (IML) of the spinal cord is an important area where sympathetic impulses propagate to peripheral sympathetic organs. ANG II and aldosterone are important components of the renin-angiotensin-aldo-sterone system (RAAS), which activate the sympathetic nervous system. Each is partly synthesized in the brain and plays a paracrine role in the regulation of blood pressure independently of RAAS in the periphery. Our purpose in the present study was to clarify the contributions of sympathetic preganglionic neurons in the IML (IML neurons) and the effects of ANG II and aldosterone on the sympa-thetic nervous system. To examine responses to ANG II and aldoste-rone, we intracellularly recorded 104 IML neurons using a whole cell patch-clamp technique in spinal cord slice preparations. IML neurons were classified into two types: silent and firing. Both neuron type