Abstract
We studied the actions of vasopressin administered microiontophoretically onto neurons of the locus ceruleus in rats with deoxycorticosterone-acetate (DOCA)-salt hypertension and in control (normotensive) rats. Rats were studied at 3 days (prehypertensive stage) and 4 to 6 weeks after DOCA-salt treatment (chronic hypertensive stage). Experiments were performed in anesthetized rats using conventional microiontophoretic and single-cell recording techniques. Three days after DOCA-salt administration, the treated rats showed no rise in arterial pressure in comparison with control rats, but 4 to 6 weeks later, the treated rats had significantly greater pressures (p less than 0.01) than controls. Vasopressin administered with currents of 10 to 90 nA for 1 minute produced a current-dependent increase in the firing rate of noradrenergic neurons in all rats. Increases in the firing rate of noradrenergic neurons in DOCA-salt-treated rats, whether in the prehypertensive or the chronic stage, were significantly greater than increases in control rats. These findings indicate that 1) vasopressin can affect neuronal activity in the locus ceruleus and 2) noradrenergic neurons in the locus ceruleus of DOCA-salt-treated rats have an increased responsiveness to the excitatory effects of vasopressin in both prehypertensive and chronic stages of hypertension.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
