Effects of an antiserum to @entity35 @entity11249 on lactation in the XXXX .

@entity35 @entity2847 @entity11249
A highly specific antiserum to rat GH (anti-rGH) was used to assess the role of GH in lactation in the @entity35 . When administered alone, anti-rGH had no effect on litter weight gain, whereas @entity2847 reduced serum prolactin concentrations and litter weight gain for up to 7 days when given on day 4 of lactation. When @entity2847 and anti-rGH were given in combination, however, litter weight gain declined even more dramatically so that pups were receiving virtually no milk 2-3 days after treatment. Daily litter exchange failed to prevent this effect. Concurrent injections of highly purified GH (prolactin contamination undetectable) prevented the dramatic decline in litter weight gain induced by combined @entity2847 and anti-rGH treatment, so that these litters grew as well as those receiving @entity2847 alone. @entity11249 did not act by influencing serum prolactin concentrations, which remained low during GH therapy. Direct effects of anti-rGH or GH on the pups (transferred through the milk) were ruled out since virtually identical results were obtained when milk yield was estimated during a 30-min suckling period after a 3-h separation of mother and pups. Lactation had virtually ceased 3 days after treatment with both @entity2847 and anti-rGH, but it could be reinitiated by a single injection of prolactin or GH, and subsequent recovery was virtually complete. The results of this study show that prolactin can maintain a full milk yield in the absence of GH, milk yield is reduced by approximately 50% in the absence of prolactin and milk yield is totally stopped in the absence of prolactin and GH.(ABSTRACT TRUNCATED AT 250 WORDS)
