The Effects of Hypoxia and Opioid Receptor Agonists Treatment in Cortical B50 Neuronal Cells in Culture

Hypoxia has been implicated in nerve cell deaths in many neurological disorders and opioid receptor agonists have some positive benefits on the nervous system. The aim of the present work was to investigate the effects of hypoxia and opioid receptor agonists' treatment on the morphology of B50 cells cultured in hypoxia using neuronal pattern and pattern formation as a case study. The B50 cells were cultured in normal incubator (21%O2; 5% CO2) as the control group and hypoxic incubator (5%O2; 5% CO2) as the experimental group and three opioid receptor agonists namely DAMGO (_), DSLET () and ICI-199,441 () were administered to the cells for 48 hours as treatment against hypoxia after 48 hours of culture at 10_M, 50_M and 100_M concentrations. Neuronal morphology and wellbeing was assessed using same field morphological assessment and lactate dehydrogenase leakage (LDH). The result showed groups of dead and degenerating B50 neuronal cells, altered neuronal pattern and pattern formation and some significant changes (P<0.05) in cellular levels of LDH leakage in normal, hypoxic cells and cells treated with different agonists. The changes in morphology, neuronal pattern and LDH release indicate that hypoxia induced morphological and cellular changes in B50 cells in hypoxia and opioid agonists have some potential benefits in the treatment of hypoxia-induced changes in B50 cells in culture.This paper is based on research funded by the World Health Organisation, the International Council ofNurses and the Royal College of Nursing of the United Kingdom. Whilst the primary focus is on the UK,general lessons related to international recruitment and migration of nurses are also highlighted.There is general agreement amongst all stakeholders in the UK that nursing shortages have become a majorfactor constraining health care delivery in the National Health Service in the UK. In order to overcomethese skills shortages, four areas of government initiative are underway: attracting more applicants to nurse education; encouraging returners to nursing employment; improving retention through improved careerstructures and flexible working practices; and recruiting nurses from abroad. NHS Plan targets for increased staffing have been one major factor in focusing attention on international recruitment.There has been a significant growth in the level on inflow of nurses from other countries to the UK.Registration data on annual admissions of nurses from non-UK sources shows a fivefold increase since theearly 1990s. In 2000/01 a total of 9,694 initial entrants on the UK Register were from all overseas sources.This figure has risen to approximately 15,000 in 2001/02, which equates to almost half of all new nursesentering the UK Register in the year.Registration data highlights that a total of more than 30,000 new non-UK nurses have registered in the UKin the last three years. The Philippines, South Africa and Australia have been the main sources.The trend in significant growth of recruitment of nurses from non-EU countries has not been matched byany growth in inflow from the countries of the European Union. In recent years the EU has reduced insignificance as a source of nurses entering the UK.The Department of Health in England issued guidance on ethical international recruitment practices in 1999requiring NHS employers to avoid direct recruitment from designated countries such as South Africa andthe West Indies. Registration data suggests that the 1999 guidelines may have had some short-term impactin reducing recruitment from South Africa and the Caribbean, but that this recruitment activity may havethen been displaced to other developing countries. The Department has issued a strengthened Code forinternational recruitment in late 2001.The pull factor of meeting NHS Plan staffing targets is likely to mean that the UK, particularly England,will continue to be active in recruiting from international nursing labour markets, partly as a result of newtargets having been set for 2008. UK government policy initiatives to increase the number of nursingstudents, and to improve retention and return rates, can have a positive effect. However, the growth in thenumber of UK nurses who can retire is likely to challenge the capacity of the NHS to retain the requirednumbers of nurses. 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