Gonadal Hormones Modulate The Responsiveness To Local β-blocker-induced Antinociception In The Temporomandibular Joint Of Male And Female Rats.

We have previously demonstrated that blockade of β-adrenoreceptors (β-AR) located in the temporomandibular joint (TMJ) of rats suppresses formalin-induced TMJ nociceptive behaviour in both male and female rats, but female rats are more responsive. In this study, we investigated whether gonadal hormones modulate the responsiveness to local β-blocker-induced antinociception in the TMJ of rats. Co-administration of each of the selective β1 (atenolol), β2 (ICI 118.551) and β3 (SR59230A)-AR antagonists with equi-nociceptive concentrations of formalin in the TMJ of intact, gonadectomized and hormone-treated gonadectomized male and female rats. Atenolol, ICI 118.551 and SR59230A significantly reduced formalin-induced TMJ nociception in a dose response fashion in all groups tested. However, a lower dose of each β-AR antagonist was sufficient to significantly reduce nociceptive responses in gonadectomized but not in intact and testosterone-treated gonadectomized male rats. In the female groups, a lower dose of β1 -AR antagonist was sufficient to significantly reduce nociceptive responses in gonadectomized but not in intact or gonadectomized rats treated with progesterone or a high dose of oestradiol; a lower dose of β2 -AR antagonist was sufficient to significantly reduce nociceptive responses in gonadectomized but not in intact and gonadectomized rats treated with low or high dose of oestradiol. Gonadal hormones may reduce the responsiveness to local β-blocker-induced antinociception in the TMJ of male and female rats. However, their effect depends upon their plasma level, the subtype of β-AR and the dose of β-blockers used

Gonadal hormones modulate the responsiveness to local β‐blocker‐induced antinociception in the temporomandibular joint of male and female rats

We have previously demonstrated that blockade of β‐adrenoreceptors (β‐AR) located in the temporomandibular joint (TMJ) of rats suppresses formalin‐induced TMJ nociceptive behaviour in both male and female rats, but female rats are more responsive. In this study, we investigated whether gonadal hormones modulate the responsiveness to local β‐blocker‐induced antinociception in the TMJ of rats. Methods Co‐administration of each of the selective β1 (atenolol), β2 (ICI 118.551) and β3 (SR59230A)‐AR antagonists with equi‐nociceptive concentrations of formalin in the TMJ of intact, gonadectomized and hormone‐treated gonadectomized male and female rats. Results Atenolol, ICI 118.551 and SR59230A significantly reduced formalin‐induced TMJ nociception in a dose response fashion in all groups tested. However, a lower dose of each β‐AR antagonist was sufficient to significantly reduce nociceptive responses in gonadectomized but not in intact and testosterone‐treated gonadectomized male rats. In the female groups, a lower dose of β1‐AR antagonist was sufficient to significantly reduce nociceptive responses in gonadectomized but not in intact or gonadectomized rats treated with progesterone or a high dose of oestradiol; a lower dose of β2‐AR antagonist was sufficient to significantly reduce nociceptive responses in gonadectomized but not in intact and gonadectomized rats treated with low or high dose of oestradiol. Conclusion Gonadal hormones may reduce the responsiveness to local β‐blocker‐induced antinociception in the TMJ of male and female rats. However, their effect depends upon their plasma level, the subtype of β‐AR and the dose of β‐blockers used196772780FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2009/16991-0; 2010/19872-

The DesertMargins Programme Approaches in Upscaling Best-Bet Technologies in Arid and Semi-arid Lands in Kenya

Kenya’s land surface is primarily arid and AQ1 semi-aridlands(ASALs)whichaccountfor84%ofthe totallandarea.TheDesertMarginsProgramme(DMP) inKenyahasmadesomecontributiontounderstanding which technology options have potential in reducing land degradation in marginal areas and conserving biodiversity through demonstrations, testing of the most promising natural resource management options, developing sustainable alternative livelihoods and policy guidelines, and replicating successful models. In extension of sustainable natural resource management, two types of strategies were used: (i) strategies for the promotion of readily available technologies and (ii) approaches for participatory learning and action research. Thus DMP-Kenya initiated upscaling of four ‘best-bet’ technologies. Under the rangeland/livestock management options, scaling-up activities include improvement of rangeland productivity, rangeland resource management through communitybasedrangeresourcesmonitoring/assessment,andfodder conservation for home-based herds. Restoration of degraded lands included rehabilitation of rangelands using the red paint approach in conservation of Acacia tortilis, control of Prosopis, planting of Acacia senegal trees in micro-catchments, and rehabilitation of degraded areas through community enclosures. Improved land, nutrient, and water management involved upscaling water harvesting and integrated nutrient management (INM) technologies. Activities A.O. Esilaba ( ) Desert Margins Programme, Kenya Agricultural Research Institute, Nairobi, Kenya e-mail: [email protected] under tree-crop/livestock interactions included upscaling of Melia volkensii and fruit trees (mangoes) and enhancing biodiversity conservation through support of beekeeping as a viable alternative livelihood. Participatory learning and action research (PLAR) was used for technology development and dissemination. Capacity building and training was a major component of upscaling of these best-bet technologies