Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00750 (PLA)
 16,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ro 15-1788, a selective benzodiazepine (BZD) antagonist, is known to precipitate withdrawal reactions in BZD-pretreated animals. We examined whether a high dose of Ro 15-1788 can precipitate withdrawal reactions relating to behavior and changes in the stress-hormone plasma levels after acute BZD treatment in man. On two consecutive days, 15 min and 24 h respectively after a single treatment with either lormetazepam (0.06 mg/kg: LMZ group), flunitrazepam (0.03 mg/kg: FNZ group) or placebo (PLA group), 18 healthy volunteers received two injections of Ro 15-1788 (0.01 mg/kg). Behavioral responses (mood changes, anxiety), cortisol and prolactin plasma levels, and physiological parameters were examined. In all groups there were only slight changes in the circulation parameters. Minor anxiety reactions were seen after Ro 15-1788, which occurred the 1st day in the PLA group and the 2nd day in the BZD groups. Depression was noted especially in the FNZ group after both injections of Ro 15-1788. The physiological morning decrease in cortisol plasma level was influenced on the 1st day in the LMZ group (2 volunteers showed high plasma levels) and the 2nd day in the FNZ group: a slight increase of cortisol plasma level was measured after the 2nd injection of Ro 15-1788. Prolactin plasma levels arose immediately after LMZ injection and continued to increase after Ro 15-1788 injection. No increase in prolactin plasma levels was found in the other groups or in the LMZ group after the 2nd challenge by Ro 15-1788.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Benzodiazepine antagonism by RO 15-1788: psychometric, hormonal and biophysical parameters]. 290 13

We have determined that the primary reason for the frequently encountered poor survival of human scirrhous breast carcinomas in short-term (4 days) organ culture is mechanical injury to the tumor tissue during explant preparation. It was possible to minimize this injury by preparing 0.5-mm-thick slices using very sharp blades. This resulted in much improved preservation of tissue structure and function, as assessed by histology, DNA content, and enzyme synthesis and secretion. With the exception of insulin, which was always present in the culture medium, exogenous hormones, including estrogen, or serum did not further improve explant preservation. In rodent mammary tumors, growth in vivo and production of the serine protease plasminogen activator (PA) in organ culture are coordinately regulated by hormones, suggesting that PA may be a valuable indicator of tumor hormone responsiveness. We have now tested the effect of estrogen and other hormones on PA secretion in organ cultures of primary human breast carcinomas. We found that: modulation of PA by 17-beta-estradiol (10-8) M) occurred only in carcinomas which were positive for both estrogen and progesterone receptors; of 21 such tumors, 11 (52%) were responsive. Plasminogen activator was not modulated by estradiol in any of the 22 tumors which were negative for one or both receptors; hydrocortisone (10(-7) M) effectively inhibited, and 3,5,3'-L-triiodothyronine (10(-8) M) and adenylate cyclase activators effectively stimulated PA in most breast tumors, regardless of their estrogen and progesterone receptor status. Prolactin (5 micrograms/ml) had no effect when tested alone; urokinase-type PA was found to be the principal PA produced by human breast tumors. Changes in its rate of synthesis and secretion and not in the content of PA inhibitors appeared to be the prevailing mechanism of enzyme regulation by hormones. In summary, short-term organ culture coupled with the use of PA as an index of response appears to be a promising approach to the study of hormone sensitivity of primary human breast carcinomas.
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PMID:Hormonal modulation of plasminogen activator: an approach to prediction of human breast tumor responsiveness. 310 11

Administration of ovine prolactin resulted in a rapid and significant induction of plasminogen activator activity within two hours in the rat adrenal gland, heart, aorta and liver. Prolactin exposure reduced baseline proteolytic activity in lung and skeletal muscle at 6-8 hours following hormonal challenge. This was coincident with a return toward baseline levels in enzyme activity demonstrated in other tissues. Pretreatment with actinomycin D or cycloheximide ameliorated the enzymic induction in the liver and adrenal and partially inhibited the aortic response. These data suggest that prolactin exposure leads to increased proteolytic activity through de novo biosynthesis in a variety of solid organs. In addition, pro-enzyme activation may also occur in vascular tissue.
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PMID:Rapid elevation of plasminogen activator activity in rat tissues by prolactin. 654 Oct 40