Blood pressure control in pithed rat.
In the pithed Wistar rats Captopril (2 mg/kg) decreased the mean arterial pressure (MAP) 21%. Further injection of a specific antagonist decreased the vasoconstrictor action of vasopressin (aAVP, 10 micrograms/kg) an additional 6%. Reversal in the order of drug administration did not change these percentages. The osmotic stimulus evoked by the infusion of hypertonic saline (ClNa 9%, 0.018 ml/min, 2 hr) significantly increased MAP, this increase being almost totally reversed by the aAVP (10 micrograms/kg). These findings suggest a greater role of the renin-angiotensin system than of the vasopressin (AVP) in the maintenance of MAP in the pithed rat; AVP, moreover, can be released by means of an osmotic stimulus.
D000818:Animals; D001127:Arginine Vasopressin / Q000037:antagonists & inhibitors / Q000502:physiology*; D001794:Blood Pressure / Q000187:drug effects; D002216:Captopril / Q000494:pharmacology; D003714:Denervation; D008297:Male; D009995:Osmosis; D051381:Rats; D011919:Rats, Inbred Strains; D012084:Renin-Angiotensin System / Q000187:drug effects
D001127:Arginine Vasopressin; D002216:Captopril