Pharmacological studies of lithium salts. III. General pharmacological actions of LiCI on cardiovascular system and smooth muscles

LiCl caused a temporary fall followed by a continuous rise on blood pressure in rat, cat and dog. The temporary fall on blood pressure was not suppressed by atropine, propranolol, diphenhydramine and vagotomy. The continuous rise was suppressed by phentolamine, hexamethonium, chlorpromazine, reserpine and pithed treatment, and only a temporary rise was observed. Also, LiCl potentiated the effects of norepinephrine and tyramine on blood pressure. Furthermore, LiCl resulted in an increased action of cardiac force and output, and a dilative action of peripheral vessels. On the other hand, LiCl had no effect on smooth muscle preparations. From these results, it is concluded that LiCl in a relatively high dose influences the circulatory system through a central action as well as direct action on the peripheral vessels and the heart muscle.