Showing papers by "John C. S. Harding published in 1997"

Recognizing and diagnosing postweaning multisystemic wasting syndrome (PMWS)

Abstract: http://www.aasp.org/shap/issues/v5n5/index.html ostweaning multisystemic wasting syndrome (PMWS) is a new disease first described in 1996.1,2 In the past 6–8, months the number of affected herds has grown considerably, and there are now confirmed cases in Alberta, Saskatchewan, Manitoba, Quebec, California, Iowa, Indiana, and Spain. Furthermore, since 1994, a similar syndrome—”wasting disease of piglets”—has been confirmed in as many as 200 herds in France.

The effects of kainic acid lesions on dopaminergic responses to haloperidol and clozapine.

Abstract: The antipsychotic drugs haloperidol and clozapine have the common action of increasing dopamine metabolism in the striatum (nucleus accumbens, caudate-putamen) of the rat. Intracerebroventricular administration of kainic acid (KA) produces neuronal loss in limbic-cortical brain regions which project directly or indirectly to the striatum. In the present study, dopamine metabolism in subregions of the striatum was examined in rats with KA lesions after acute and chronic haloperidol or clozapine administration. The main findings was that the elevating effect of acute haloperidol treatment on the dopamine metabolite, DOPAC, was blocked in the nucleus accumbens shell and diminished in medial and laterodorsal caudate-putamen of the KA-lesioned rats. In addition, the elevating effects of both acute and chronic haloperidol treatment on dopamine turnover were attenuated in the laterodorsal caudate-putamen of KA-lesioned rats. The levels of dopamine, DOPAC, and HVA after chronic clozapine treatment were greater in KA-lesioned than control rats. These results indicate that dopaminergic responses to haloperidol may be diminished by limbic-cortical neuropathology, while such pathology does not significantly alter dopaminergic responses to clozapine.