[Monoamines stimulations in experimental carcinogenesis].
Facts about the role of CNS monoamines in cancerogenesis have been accumulated for many years. The aim of the present study was to investigate the effect of interaction of psychoactive drug (Piracetam) and other treatments on survival time of tumour-bearing rats. 138 Wistar rats were used in the experiment. The animals were injected 1% 3--Methilcholantren suspension in 10% Tylose, s.c. under the dorsal skin of the neck in a dose of 3 mg/animal. Within 4-9 months after a single injection, the rats developed tumours at the site of injection. The surgical removal was performed when tumours reached the size of 1-3 cm. After surgical extirpation of tumours different groups of animals were treated by cyclophosphamide (s.c. one-time dose of 50 mg/kg for female and 100 mg/kg for male) or by psychoactive drug (Piracetam) administrated by GE tube 5 time/week, 100 mg/kg. Autopsy and histological examinations were carried out in all animals. Survival time (> 120 days) was the greatest in group B (Piracetam, after surgical removal of tumours) 81.2%, and group C (Cyclophosphamid, after surgical removal of tumours) 68.8% and in group A (only surgical removal of tumours) 50%. In group B the incidence of metastases was the smallest (87.1% of animals were without metastases), compared with group C (45.4% of animals were without metastases) and group A (27.3% of animals were without metastases). The diference is statistically significant. The mechanism of antineoplastic effect of Piracetam consisted of the interaction of influences both on metabolism of the Central nervous system and the tumour. Probably, it is the neurotransmitter modulation that had its effect on carcinogenesis not only by regulation/disregulation of brain homeostasis, but also via direct effect on intracellular processes during cell development and differentation.
Popov
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I
Spuzić
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Rakić
Lj
Lj
D000818:Animals; D015306:Biogenic Monoamines / Q000494:pharmacology; D005260:Female; D008297:Male; D009362:Neoplasm Metastasis / Q000517:prevention & control*; D009369:Neoplasms / Q000139:chemically induced*; D010889:Piracetam / Q000494:pharmacology*; D011619:Psychotropic Drugs / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D015306:Biogenic Monoamines; D011619:Psychotropic Drugs; D010889:Piracetam