ABSTRACT
1. A previous study form our laboratoy demostrated the occurrence of transient tachycardia during the onset of one-kidney, one clip (1KIC) hypertension in conscious rats. In the presente study, using electroneurographic recording in anesthetized rats, we investigated the time course of baroreceptor resetting at the onset (3, 7, 14 and 21 days) of 1K1L hypertension. 2. there was no significant difference between the diastolic pressure of hypertensive animals and the systolic thershold pressure for baroreceptor activation in normotensive control rats (100 ñ 3 vs 92 ñ 5mmHg), and hypertensive rats 3(118 ñ 3 vs 112 ñ 5mmHg), 7(125 ñ 6 vs 119 ñ 5 mmHg), 14(135 ñ 11 vs 125 ñ 10mmHg) and 21(154 ñ 6 vs 150 ñ 8mmHg) days after clipping. 3. These data indicate that the baroreceptors were completely reset to the hypertensive levels during the periods studied and also suggest that baroreceptor resetting may play a facilitatory role for the onset of tachycardia and the development of 1K1C hypertension in the conscious animal model