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.     

Phagocytosis of liposomes by mouse peritoneal macrophages (author's transl)]

Uptake of 14C-cholesterol or 3H-cholesterol labelled liposomes, stimulation of 14C-glucose oxidation, as well as ultrastructural and autoradiographical experiments have shown that liposomes are phagocytized by mouse peritoneal macrophages. Further results have shown that degradation of liposomes was not complete 2h after uptake.     

Sexual steroids and monamine metabolism during gestation.

The experiments show influence of progesterone and estradiol on regulation of enzymes of monamine metabolism, MAO and COMP during pregnancy. Both the hormones inhibit enzymes MAO and COMPT in the adrenals when determined at 0 h parturition. Estradiol has stronger inhibitory effect than progesterone. The results provide evidence for important endocrine implication during pregnancy for processes of monamine regulation.     

Anionic activation of human salivary amylase.

In all earlier studies on alpha-amylase, the influence of different ions were studied in phosphate buffer. The present report shows the effect of different ions individually with Tris and amino acid. Though it has been claimed recently that sodium ion is an activator of alpha-amylase, this study reconfirms that sodium ion does not activate human salivary amylase.     

Myopathic changes at the end-plate region induced by neostigmine methylsulfate.

Administration of large dose of neostigmine caused very quickly marked myopathic changes at the motor end-plate region. With continued injections, however, some recovery of the structural features did occur suggesting the reconstructive changes in the affected regions.     

Influence of the visual cortex upon collicular evoked responses in the rabbit.

In rabbit, the depression of the visual cortex by KCl showed an enhancement of the collicular evoked potentials. This enhancement revealed that the visual cortex had exerted a tonic type influence upon the superior colliculus.