Behavioral and cardiovascular measures were obtained from spontaneously hypertensive (SHR) and matched normotensive (WKY) male rats before, during, and after exposure to electric footshock. During shock, SHRs jumped more frequently and were more active than WKYs. Transfer from the home cage to the shock chamber resulted in a greater increase in heart rate and mean arterial pressure in SHRs than in WKYs. During footshock, however, in SHRs, the mean arterial pressure decreased although the heart rate increased. Both mean arterial pressure and heart rate increased during shock in WKYs.