1. Neither nerve-growth-factor antiserum (NGFAS) administered subcutaneously nor 6-hydroxydopamine administered intraventricularly to immature spontaneously hypertensive rats (SHR) inhibited the development of the hypertensive syndrome. In contrast, NGFAS did not affect blood pressure in normotensive Kyoto/Wistar rats.
2. Peripheral vascular resistance was increased and cardiac index decreased in both NGFAS and 6-hydroxydopamine-treated SHR despite preservation of normal blood pressure.
3. NGFAS treatment did not influence the development of left ventricular hypertrophy in SHR, despite the lowering of blood pressure. In contrast, 6-hydroxydopamine caused an attenuation in the development of left ventricular hypertrophy.
4. Indices of left ventricular contractility were depressed by NGFAS treatment but not by 6-hydroxydopamine.
5. Plasma renin activity was unaffected by NGFAS treatment and increased by 6-hydroxydopamine.