[Hypothalamoneuropituitary activation during vasodilatator perfusion in normal individuals (author's transl)]

The hypothalamo-neurohypophyseal function has been tested in 9 normal individuals (age 22 - 50; 2 women and 7 men) in the course of a vasodilatator perfusion (sodium nitroprussiate) in standardized conditions. Vasopressin-neurophysin (hNPI), oxytocin-neurophysin (hNPII) and total immunoreactive neurophysins (IRN) have been assayed. Our preliminary results show a clear-cut increase of hNPI and IRN when the decrease of the mean blood-pressure exceeds 20 +/- 10% (15 - 33). There is only a weak, if any, increase of hNPII. There is a highly significant relationship (r : 0.90, p less than 0.01) between maximal increment of IRN and maximal increment of heart frequency suggesting a similar way of activation. Vasodilatator perfusion could be, in the future, a reliable test for hypothalamo-neuropituitary function although it's reproducibility has still to be deeper investigated.