TOXICOLOGICAL STUDIES ON THE LATEX OF THE USHER PLANT CALOTROPIS-PROCERA (AIT) RBR IN SAUDI-ARABIA .2. ULTRASTRUCTURAL-CHANGES IN THE CARDIAC-MUSCLE AND VARIATION IN THE BLOOD-SERUM COMPOSITION OF TREATED ALBINO-RATS

The toxic effects of the clean latex extract of the Usher plant has be en investigated by the intraperitoneal inoculation of rats with lethal (100%; eq. to 50.5 mg digitoxin) and sublethal (33%; eq. to 16.8 mg d igitoxin) doses of the extract. Both doses used caused significant flu ctuations in several blood constituents. comprising significant increa ses in Na+, K+ ions, glucose, creatinine, urea, bilirubin and in the e nzyme activities of GPT, GOT, CPK and LDH, with significant decreases in total protein contents, albumin and in the activities of the enzyme s GGT and ALP. The cardiac muscle showed an increase in the number of mitochondria accompanied with mitochondrial swelling and lysis of mito chondrial membranes and cristae. There was some focal myofilaments fra gmentation (lysis). as well as absence of muscle striations due to con traction as reflected by the disappearance of I- A-bands, Z-zone and M -line. The glycogen granules have also disappeared from some of the ca rdiac muscle fibers. These changes arc brought about mainly by the sub lethal dose of the latex, while the lethal dose brings about mainly qu ick death of treated animals.