Neurotrophic effects of prolactin on TIDA neuronal development

Neurotrophic effects of prolactin on TIDA neuronal development 

Dwarfism in the mouse is an hereditary trait the affected mice exhibit retarded postnatal growth, lack of estrous cyclicity, hypothermia and sterility. The primary deficit in the two major types of dwarf mice (Snell and Ames) is in the anterior pituitary, which is deficient in the production and release of prolactin, GH and thyrotropin (for review, see Phelps, 1994). The adult dwarf mice also have a deficit in TIDA neurons the content and rate of synthesis of DA in the median eminence, and numbers of TH-IR perikarya in the ARC are markedly reduced. This deficit appears selective for TIDA neurons as there is no change in the numbers of DA perikarya in the MZI (IHDA neurons) or substantia nigra (nigrostriatal DA neurons). 

Prior to postnatal day 21, the characteristics of the TIDA neurons in dwarf mice cannot be distinguished from those in the normal littermate controls. That is, the DA content in the mediobasal hypothalamus and the number of TH-positive perikarya are the same in dwarf and normal mice. After 21 days of life, TIDA neurons in the dwarf mice regress such that their number at 60 days of age is less than it is at 21 days. This could represent the 

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