I. P. Pavlov on animal experiments]

The paper is dedicated to the 150th anniversary of academician I.P. Pavlov's birthday. Pavlov's points of view on vivisection are analyzed and are compared with the modern conception of ethics of carrying out experiments on animals. It is discovered that Pavlov's points of view are in accordance with the key positions of modern requirements to ethics of experimenting on animals which are adopted in the world practice.     

Effect of bile acid analogs on 7 alpha-dehydroxylase activity in Eubacterium sp. V.P.I. 12708

7 beta-Methyl-chenodeoxycholic acid (7-MeCDC, 3 alpha, 7 alpha-dihydroxy-7 beta-methyl-5 beta-cholan-24-oic acid), 7 alpha-methyl-ursodeoxycholic acid (7-MeUDC, 3 alpha, 7 beta-dihydroxy-7 alpha-methyl-5 beta-cholan-24-oic acid), 7 xi-methyl-lithocholic acid (7-MeLC, 3 alpha-hydroxy-7 xi-methyl-5 beta-cholan-24-oic acid) and ursodeoxycholylsarcosine (UDCS) were tested as inhibitors of bacterial bile acid 7 alpha-dehydroxylase activity. At a concentration of 50 microM, 7-MeCDC and 7-MeUDC inhibited enzyme activity by 66% and 12%, respectively. 7 alpha-Dehydroxylase activity was not inhibited in the presence of 7-MeLC and UDCS. None of the four bile acid analogs tested inhibited the growth of Eubacterium sp. V.P.I. 12708 at concentrations up to 100 microM.     

An historical-physiological analysis of the discussion between I. P. Pavlov and V. M. Bekhterev on the problems of localizing functions in the cerebral cortex

This article is the first of the domestic publications on physiology and medical history, which highlights the discussion between I. P. Pavlov and V. M. Bekhterev on the issue of localization of functions in human cerebral cortex: it provides information of the visit by I. P. Pavlov to the clinic of V. M. Bekhterev; it discusses the role of V. M. Bekhrerev's students who described the cortex zones of tonotopics, gustation, regulation of salivation and stomach secretion, which I. P. Pavlov denied. Unlike articles on factography and history of physiology, which in various ways praise the scientists, this article is based of the modern approaches of medical history and scientific knowledge, in particular, it provides a retrospective of the major facts of the discussion.     

I. P. Pavlov on vivisection and the modern ethical requirements for animal experiments]

It is shown that Pavlov's opinion is in agreement with the modern requirements for experiments in living animals: use of living animals in experiments is recommended only in the cases when there is no alternative and scientific-practical significance of the planned experiments is justified; minimization (as much as possible) of discomfort, distress and pain of animals under study without sacrifice of the quality of scientific research; use of appropriate number of animals necessary for obtaining reliable results which are adequate to a given experimental situation and general state of the animals inadmissibility of using extra number of animals; drawing up a protocol concerning the experimental procedure and results; reflection in the protocol the techniques of sedation, anesthesia, and euthanasia; constant care of the improvement of the theoretical and practical qualification of a researcher in the ethical questions and experimental technique. Pavlov's views led his time and at present they agree with modern concepts on the experimental ethics.     

Update on animal models developed for analyses of estrogen receptor biological activity

Targeted disruption of the different ER genes has generated experimental animal models that are very useful in evaluating the distinct and cooperative roles of the two estrogen receptors, ER and ERβ, in reproductive but also non-reproductive tissues of both sexes. Phenotypic analysis has provided definitive experimental findings for estrogen receptor mediated physiological actions, involving ER in uterine, mammary gland and neuroendocrine sites. ERβ is involved most dramatically in the ovary as is ER. More detailed studies in combination with tissue specific or inducible ER knock outs will be important for future research.     

Peptide transport across the animal cell plasma membrane: recent developments.

Transfer of intact peptides across the plasma membrane of animal cells, especially in the small intestine and the kidney, is a well established phenomenon. This process plays an important role in the maintenance of protein nutrition. Evidence is accumulating which suggests that the process may also have a great potential for pharmacological and clinical applications. It is therefore important to understand various aspects of peptide transport such as its function, chemical nature of the transport protein and its gene, the operational mechanisms and their regulation, and the relevance of the transport system to health and disease. Recent years have witnessed considerable progress in the field. The driving force for the transport system has been identified as the proton motive force which makes the system unique and distinct from the majority of solute transport systems in animal cells which are driven by a sodium motive force. A great deal is now known on the chemical nature of the active site. The protein responsible for the transport process in the small intestine has been purified and characterized. The system has been successfully expressed in its functional form in Xenopus laevis oocytes by microinjection into the oocytes of poly(A)+ mRNA isolated from intestinal mucosal cells. There is no doubt that the coming years will bring even more exciting information on the transport system, especially in areas such as hormonal regulation, clinical applicability and cloning, and characterization of the gene encoding the transport system.     

I. P. Pavlov's theory on higher nervous activity: the landmarks and trends in its development

The theory of higher nervous activity created in Pavlovian time is compared with the present-day state of the theory developing due to appearance of new methods, techniques, facts, and concepts. Three principles of Pavlovian theory: determinism; analysis and synthesis; structural approach, as well s types of conditioned reflexes and techniques, types of higher nervous activity, and inhibition problems are discussed. The theory of higher nervous activity is schematically depicted as a tree, some branches of which are presented by facts and concepts obtained and introduced by I.P. Pavlov and his followers during his life, the others are formed by new facts and concepts advancing the theory. What is obsolete in the theory, what are the most prominent tendencies of its development and its new branches are discussed.