Effect of prolactin on blood pressure and cardiovascular responsiveness in the XXXX .

@entity35 @entity1063 @entity1508 @entity1017
The effects of chronic ovine PRL (oPRL) infusion on resting systolic blood pressure (BP), heart rate, and pressor responsiveness to acute administration of @entity1063 and angiotensin were studied in adult male @entity35 . oPRL was administered over 7 days, via osmotic pump implanted ip on Day 1, at rates of 0, 0.15, 0.30, 0.60, 1.20, and 4.80 micrograms/hr. Resting BP and heart rate were indirectly determined in conscious @entity35 by tail cuff technique on Days 1, 4, and 7 following pump implantation. In addition, acute pressor responses to ia @entity1063 (4.3 micrograms) and angiotensin (1.25 micrograms) were directly measured via arterial cannula in @entity1508 -anesthetized @entity35 on Day 7 of oPRL administration. oPRL infusion did not alter resting BP or heart rate over the 7 days. However, oPRL increased the BP response to @entity1063 at infusion rates of 0.60 and 4.80 micrograms/hr (P less than 0.01 vs controls). Body weight increases during the study were also greater in groups receiving 0.15, 0.30, 0.60, and 4.80 micrograms oPRL/hr (P less than 0.05) than those in control animals. oPRL decreased pressor responses to angiotensin at infusion rates of 0.30 and 1.20 micrograms/hr (P less than 0.01). These data suggest that, although the vascular effects of oPRL may not be evident under resting conditions, oPRL enhances vascular reactivity to @entity1063 infusion and depresses vascular reactivity to angiotensin infusion. Furthermore, at oPRL infusion rates which affect pressor responses to @entity1063 , oPRL increases body @entity1017 . These findings support a role for PRL in cardiovascular regulation during conditions of altered sympathetic activity.
