650
ILSE L A S N I T Z K I
The use of contact-cultures has shown that the anterior pituitary,
the gonads and the parathyroid gland elaborate and release hormones
in culture which produce similar effects to those seen after application
of the commercial preparations of the same hormone.
The study on the action and interaction of hormones on the development of the mammary gland gives a fascinating picture of the effects
of individual hormones on different parameters of growth and differentiation of the mammary epithelium which together make up a composite whole, and shows up the variation of hormonal effects with
different developmental stages of the gland. Differences in growth rate
were found to determine the response of limb-bone rudiments to
thyroxine ( T 4 ) and triiodothyronine ( T 3 ) .
Attempts to correlate morphological changes with alterations of the
metabolic pattern in hormone-treated cultures by biochemical or
cytochemical means have yielded valuable information on the mechanism of hormone action.
The growth-promoting activity of insulin could be traced to an
enhancement of carbohydrate metabolism and protein synthesis; bone
resorption by parathormone was preceded by a reduction of enzymes
involved in carbohydrate utilization, and the retardation of bone
growth by corticosteroids to an inhibition of chondroitin sulphate
synthesis.
It is hoped that, in future work, this study will be extended to include
a greater number of hormones; constant improvements in culture
techniques and of defined media will facilitate this research and ensure
not only qualititative but also precise quantitative data under wellcontrolled experimental conditions and these should enable us to link
hormonal action at the cellular level with that at the molecular level.
R E F E R E N C E S
Ahren, K . and Jacobson, D . (1956). M a m m a r y growth in hypophysectomized rats
injected with hormones and insulin. Acta physiol. scand. 37, 190.
Algard, F. T . (1960). Hamster flank organ and kidney tumours in vitro. J. nat. Cancer
Inst. 25, 557.
Bakker-Sauer, E. K . (1961). Some effects o f thyrotropic h o r m o n e on thyroid tissue
in vitro. Koninkl. Nederl. Akad. Wetenschap. Proc. C 64, 86.
Barnicot, N . M . (1947). T h e supravital staining o f osteoclasts with neutral red, their
distribution on the parietal bone o f normal growing mice and a comparison with
the mutants grey-lethal and hydrocephalus. Proc. roy. Soc. B 134, 467.
Bergner, G. E. and Deane, W . H . (1948). Effects o f pituitary adrenocorticotropic
hormone on the intact rat with special reference to the cytoplasmic changes in
the adrenal cortex. Endocrinology 43, 240.
Bern, H . A . , Alfert, M . and Blair, S. M . (1956). Cytochemical studies o f keratin
formation and o f epithelial metaplasia in the rodent vagina and prostate. J.
Histochem. Cytochem. 5, 105.
ILSE L A S N I T Z K I
The use of contact-cultures has shown that the anterior pituitary,
the gonads and the parathyroid gland elaborate and release hormones
in culture which produce similar effects to those seen after application
of the commercial preparations of the same hormone.
The study on the action and interaction of hormones on the development of the mammary gland gives a fascinating picture of the effects
of individual hormones on different parameters of growth and differentiation of the mammary epithelium which together make up a composite whole, and shows up the variation of hormonal effects with
different developmental stages of the gland. Differences in growth rate
were found to determine the response of limb-bone rudiments to
thyroxine ( T 4 ) and triiodothyronine ( T 3 ) .
Attempts to correlate morphological changes with alterations of the
metabolic pattern in hormone-treated cultures by biochemical or
cytochemical means have yielded valuable information on the mechanism of hormone action.
The growth-promoting activity of insulin could be traced to an
enhancement of carbohydrate metabolism and protein synthesis; bone
resorption by parathormone was preceded by a reduction of enzymes
involved in carbohydrate utilization, and the retardation of bone
growth by corticosteroids to an inhibition of chondroitin sulphate
synthesis.
It is hoped that, in future work, this study will be extended to include
a greater number of hormones; constant improvements in culture
techniques and of defined media will facilitate this research and ensure
not only qualititative but also precise quantitative data under wellcontrolled experimental conditions and these should enable us to link
hormonal action at the cellular level with that at the molecular level.
R E F E R E N C E S
Ahren, K . and Jacobson, D . (1956). M a m m a r y growth in hypophysectomized rats
injected with hormones and insulin. Acta physiol. scand. 37, 190.
Algard, F. T . (1960). Hamster flank organ and kidney tumours in vitro. J. nat. Cancer
Inst. 25, 557.
Bakker-Sauer, E. K . (1961). Some effects o f thyrotropic h o r m o n e on thyroid tissue
in vitro. Koninkl. Nederl. Akad. Wetenschap. Proc. C 64, 86.
Barnicot, N . M . (1947). T h e supravital staining o f osteoclasts with neutral red, their
distribution on the parietal bone o f normal growing mice and a comparison with
the mutants grey-lethal and hydrocephalus. Proc. roy. Soc. B 134, 467.
Bergner, G. E. and Deane, W . H . (1948). Effects o f pituitary adrenocorticotropic
hormone on the intact rat with special reference to the cytoplasmic changes in
the adrenal cortex. Endocrinology 43, 240.
Bern, H . A . , Alfert, M . and Blair, S. M . (1956). Cytochemical studies o f keratin
formation and o f epithelial metaplasia in the rodent vagina and prostate. J.
Histochem. Cytochem. 5, 105.