Indirect adrenergic effect of histamine in human cerebral arteries: influence of post-mortem period.

Histamine (10(-4) M) increased the radioactivity released from human cerebral arteries obtained within 6 h of death and preincubated with [3H]noradrenaline. In the presence of 10(-6) M cocaine or if 7 or more hours had elapsed since death, 10(-4) M histamine was unable to change basal levels of tritium outflow. The radioactivity retained by the tissue was higher when cerebral blood vessels were obtained within a post-mortem period of 6 h. These results suggest that histamine may release noradrenaline from the sympathetic innervation of human cerebral arteries and that the function of this innervation lasts only 6 h after death.