[Role of enzymes of dopamine metabolism in the regulation of prolactin and thyrotropin secretion in hyperprolactinemia].

Altogether 24 women with the syndrome of hyperprolactinemia (SH), including 5 patients with significant PRL hypersecretion against a background of macro- and microprolactinemia, and 19 women with normoprolactinemic galactorrhea were investigated. The activity of dopamine-B-hydroxylase (DBH) and monoamino oxidase (MAO) (the key enzymes of dopamine metabolism) was determined by spectrophotometry. A different time course of secretion of PRL and TSH in metoclopramide testing was revealed in the patients with regard to the level of basal prolactinemia.

Overabundance of rare-cutting restriction endonuclease sites in the human genome.

A human chromosome 3-specific cosmid library was constructed from a somatic cell hybrid containing human chromosome 3 as its only human component. This library was screened to identify 230 human recombinants which contained an average insert size of 37 kilobases. DNA prepared from 54 of these cosmids, representing 2000 kilobases of human DNA, was then tested for restriction endonuclease sites for EcoRI, HindIII, KpnI, XhoI, and DraI, as well as those of the rare-cutting restriction endonucleases NotI, SfiI, NruI, MluI, SacII, and BssHII.