| Abstract: | 5 min exposure of inbred Maudsley Reactive male rats to intermittent foot-shock resulted in an approximate doubling of plasma atrial natriuretic peptides ANP (Control grp mean = 62.12 +/- 8.74; Stressed grp mean = 128.70 +/- 26.63 pg/ml) and 25 min exposure resulted in a three-fold increase (Stressed grp mean = 187.88 +/- 39.24 pg/ml). In the second experiment exposure of genetically heterogeneous Wistar male rats to 15 min of intermittent foot-shock produced a 10-fold increase in plasma ANP (Control grp mean = 45.76 +/- 6.05; Stressed grp mean = 471.20 +/- 58.49 pg/ml). The magnitude of the increase in plasma ANP produced by acute stress is as large as the increase caused by volume expansion and administration of various pharmacological agents and therefore delineation of biological role of ANP must take account of its potential role as a stress-hormone. |
