The polyamines spermidine and spermine and the activity of the polyamine synthesizing enzyme, S‐adenosyl‐L‐methionine (SAM) decarboxylase, were measured in regions of adult rat brains and during postnatal development. In the adult, although spermidine levels tended to correlate with the relative amounts of white matter in some areas, there were striking exceptions. SAM decarboxylase activity of the adult brain was higher than in most other mammalian tissues, although brain levels of polyamines were among the lowest. SAM decarboxylase activity appeared to be localized to cellular cytoplasm. Its activity increased with age in contrast to the levels of spermine, spermidine, DNA and RNA which decreased during postnatal development.

The post partum resumption of cyclic ovarian activity was followed up by regular rectal palpation and milk progesterone assay on 249 Holstein-Friesian and crossbred cows under Hungarian large scale farm conditions. The most frequent abnormalities were delayed start of cycling (36.1 YO), cycles of irregular length (17.3 %), cystic degeneration of the ovaries (16.5 YO), cessation of cyclicity (7.6 YO) and persistent corpus luteum (2.4 Yo). Sometimes more than one abnormality occurred in the same animal. The duration of the postpartum acyclic period correlated with the daily milk production at the peak of lactation.An increased acyclic period after calving was more frequent among heifers and cows after their fourth calving, while the occurrence of other abnormalities increased parallel to age.Ovarian dysfunction was more frequent in high yielding cows and, except for cystic ovarian degeneration, after involutional disturbances.The disturbed resumption of ovarian cyclicity had a detrimental effect on the re-conception.

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The authors used a combined behavioral and neuroendocrinological strategy to investigate the relevance of abnormalities in the brain dopaminergic systems to the pathophysiology of tardive dyskinesia by assessing the effects of apomorphine, a directly acting dopamine agonist, and d-amphetamine, an indirectly acting dopamine agonist, in patients with tardive dyskinesia. Administration of I.V. d-amphetamine increased dyskinetic movements in most patients with tardive dyskinesia, a finding consistent with the dopaminergic hypothesis. Contrary to predictions based on animal models, apomorphine did not increase dyskinetic movements in these patients but instead substantially reduced dyskinesia in some patients. Patients with tardive dyskinesia did not have a greater drop in serum prolactin or a greater rise in serum growth hormone after apomorphine than normal or chronic schizophrenic subjects without tardive dyskinesia.