Endocrine Abstracts

The neuroendocrine cascade regulating episodic growth hormone (GH) secretion plays a central role in post-natal growth and metabolism. Intermingling of GH cells with other pituitary cell types and the complex distribution of the hypothalamic GHRH neurons makes both the cell types difficult targets for selective physical or chemical manipulation. On the other hand, they are excellent targets for physiological transgenesis since their major secretory products derive from highly ...

Iain CAF Robinson, National Institute for Medical Research, Mill Hill, London, UK AbstractIain Robinson was born in 1949 and educated at the King Edward VII Grammar School in Sheffield before going to Worcester College, Oxford, to study physiology and medicine. Awarded first class honours in physiology and with medical studies deferred, Iain received an MRC studentship Award for studies on endocrine physiology in the D...

Pituitary hormones are released into the bloodstream in a pulsatile fashion in response to stimuli from their hypothalamic regulators. For efficient generation of hormone pulses, both the hypothalamic mechanisms and the pituitary target cells must exhibit a high degree of coordinated secretory activity. This is particularly important for the growth hormone (GH) axis since the target tissue responses are critically dependent on the temporal pattern of GH exposure, as well as th...

Animal and clinical models of GHRH excess suggest that GHRH provides an important trophic drive to pituitary somatotrophs. Mice in which GHRH neurons have been ablated using a novel viral ion channel transgene (GHRH-M2 mice) show marked anterior pituitary hypoplasia and GH deficiency although GH cells are present. GHRH-M2 mice are also deficient in prolactin which is surprising as GHRH has little or no direct effect on PRL synthesis or release (Le Tissier, Mol Endo 19). In mic...