1. The rise in blood pressure in Dahl salt-sensitive rats that received intracerebroventricular 6-hydroxydopamine was almost half that of the control rats throughout 20 weeks of high (8%) NaCl feeding.
2. The rise in bood pressure in Dahl salt-sensitive rats with bilateral complete electrolytic lesions of the paraventricular nuclei was almost half that of the control rats during 12 weeks of high (8%) NaCl feeding.
3. The bilateral complete electrolytic lesions of the suprachiasmatic nuclei enhanced the development of NaCl hypertension in Dahl salt-sensitive rats.
4. These results show that NaCl-induced hypertension in Dahl salt-sensitive rats requires the integrity of the central nervous system catecholaminergic neurones and the paraventricular nuclei for its full expression.