Hemorrhage in DOC-salt hypertensive rats: plasma and platelet vasopressin.
The effect of two consecutive hemorrhages, each 10% of blood volume, on plasma vasopressin concentrations was determined in conscious unilaterally nephrectomized Long-Evans rats made hypertensive by treatment for 3 wk with deoxycorticosterone (DOC) and substitution of 1% saline for drinking water (DOC-salt rats) or DOC alone (DOC rats) and in normotensive unilaterally nephrectomized rats drinking water (H2O rats) or saline (NaCl rats). In response to 20% hemorrhage, blood pressure decreased more (P less than 0.01) and plasma vasopressin increased less (P less than 0.01) in the DOC-salt rats than in the other groups. Under basal conditions, immunoreactive vasopressin was found in the platelets in NaCl, DOC, and DOC-salt rats (P less than 0.01) but not in H2O rats. Platelet vasopressin increased (P less than 0.05-0.01) in response to hemorrhage only in DOC-salt rats. In conclusion, the vasopressin response to hemorrhage in DOC-salt rats is impaired; platelet immunoreactive vasopressin is of little importance in normal rats but is increased by treatment with DOC and/or chronic salt loading; and platelet vasopressin increased in response to hemorrhage only in DOC-salt rats.
D000818:Animals; D001792:Blood Platelets / Q000032:analysis*; D001810:Blood Volume; D003900:Desoxycorticosterone; D006470:Hemorrhage / Q000150:complications*; D006973:Hypertension / Q000139:chemically induced / Q000150:complications*; D008297:Male; D009392:Nephrectomy; D051381:Rats; D012462:Saline Solution, Hypertonic; D013997:Time Factors; D014667:Vasopressins / Q000097:blood*
D012462:Saline Solution, Hypertonic; D014667:Vasopressins; D003900:Desoxycorticosterone