Lipoperoxidation rates and drug-oxidizing enzyme activities in the liver and placenta of some mammal species during the perinatal period.

Lipoperoxidation and drug-metabolizing enzymes were measured in livers and placentas of different mammal species during the perinatal perios. In placentas and fetal livers of rat, rabbit and guinea-pig, cofactor-supported lipoperoxidation was negligible, as were the activities of drug-oxidizing enzymes. Human fetal liver contained an intact drug-oxidizing electron transport chain, and lipoperoxidation activity was accordingly abserved. It is suggested that lesions mediated by lipoperoxidation may be possible in human fetus, but they are less probable in animal fetuses.     

Studies in relation to endocrine exophthalmos: the biochemical composition of human retrobulbar connective tissue.

As part of studies on the pathogenesis of exophthalmos of Graves' disease, the biochemical composition of human retrobulbar tissue was investigated. The connective tissue was composed of 72.7% lipid, 23.8% water and 3.5% dried defatted tissue. Total tissue glycosaminoglycan (GAG) amounted to 0.18% of dried defatted tissue. Approximately 27% of the total hexosamine and 19% of the total tissue galactosamine were recovered in the GAG fraction. Cellulose microcolumn fractionation of GAG showed that the hyaluronic acid and dermatan sulfate were the two major GAG species.     

Comparison of the ototoxic effect of kanamycin on albino and pigmented rats, studied using an operant method.

A study was made of the effect of daily administration of kanamycin (400 mg kg-1) on the hearing of Wistar albino and Lister hooded (pigmented) rats, which had been conditioned to discriminate an acoustic signal. In all animals except one, the drug caused severe, permanent hearing impairment and there was no difference between albino and pigmented rats in onset or degree. Other work has suggested a mediatory role for melanin pigment in such drug ototoxicity but the significance of this must be questioned in view of the failure to find any differences in functional deficit.     

Acute effects of tolamolol on renal function in hypertensive patients.

The renal heamodynamic effects of a single i.v. administration of tolamolol were studied in 9 hypertensive subjects. No change of GFR and ERPF was observed after tolamolol, while urine output decreased and urine creatinine concentration increased. A reduction of the heart rate was confirmed. Blood pressure was unchanged.