THE MUSCLE RELAXANT ACTIVITY OF NEPHILATOXIN FOUND IN THE VENOM OF THE PHILIPPINE SPIDER NEPHILA PILIPES (ARANEIDAE)

ABSTRACT: The active compound of the venom of the Philippine spider, Nephila pilipes was determined to be a neurotoxin acting presynaptically on the neuromuscular junction. These toxins contain polypeptides and proteins, which are responsible for causing irritation, cramped breathing, delirium, paralysis or even death on test animals. The venom glands were extracted from the spider by dissection method. Glands were squeezed in distilled water to form the crude venom. The solution was used for the preliminary testing and experiment proper. The biological test animals used were Swiss mice and chicks. The venom solution was administered intraperitoneally and intramuscularly respectively. The effects of the venom, based on the parameter of convulsion and paralysis were compared with that of the Pancuronium bromide and succinylcholine, which are the control drugs. The relative decrease in the amplitude of muscle contraction of the venom-injected muscle was also compared with that of the control drug-injected muscle, using the Polygraph machine. The venom, containing neurotoxin, could serve as an alternative source of muscle relaxant if proven safe and effective.

Department of Pharmacology