Effects of Himanthalia elongata on the central nervous system of mice.

The effects of a Himanthalia elongata extract were studied on the CNS of mice. A rich protein solution obtained from the seaweed was assayed for myorelaxant, anticonvulsant and analgesic activity and for its effects on spontaneous locomotor activity, amphetamine-induced hypermotility, exploratory behaviour, barbiturate-induced sleep, and body temperature. Very significant reductions in spontaneous motor activity, hypermotility and exploratory behaviour were found. The extract prolonged barbiturate-induced sleep and postponed pentylenetetrazol-induced death. Weak myorelaxant, hypothermic and analgesic effects were also observed, showing that H. elongata can depress the CNS.