RT Journal Article SR Electronic T1 EFFECTS OF TRIVALENT AND PENTAVALENT ARSENIC ON HEART PULSATIONS OF THE SILKWORM JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 277 OP 285 VO 28 IS 2 A1 F. L. CAMPBELL YR 1926 UL http://jpet.aspetjournals.org/content/28/2/277.abstract AB Three phases of heart activity and of general behavior follow administration to the silkworm of lethal doses of trivalent or of pentavalent arsenic: first, a period of vigorous, regular, and often, accelerated heart pulsations during which the larva is motionless; second, a period of more or less rapid decline in heart rate during which the larva squirms; third, a period of irregular pulsations and diminution in amplitude of beat during which squirming ceases. Trivalent arsenic seems to differ in its effect from the same dose of pentavalent arsenic only in its greater speed of toxic action.